Archive for lens review

Canon 24-70mm f2.8L vs Sigma f2.8 IF EX DG HSM

Posted in Articles about Photography, Lens Review, Photography Gear, TCBlog with tags , , , , , , , , , , , , on August 2, 2011 by Darwin

Note: To see all future reviews please note this blog is no longer active, please visit me over at oopoomoo.com

On full frame cameras a 24-70mm lens is the standard zoom lens for most professional photographers whether you shoot weddings, portraits, journalism, sports, travel or landscape. A 24-70 f2.8 gives you a fast lens with a wide angle, normal and short telephoto capabilities. Almost every professional I know owns and relies on a 24-70mm lens.

For years I owned a Canon 24-70mm f2.8L lens and it was a workhorse lens for me especially for my photographs of dogs and kids and outdoor recreation.. I also used it for landscape photography (until I started using tilt-shift lenses). I sold my lens about two years ago anticipating that Canon would release a Mark II version of the lens that was image stabilized and a bit sharper and with less distortion at the wide end. To date (August 2011), that lens is not yet out. So for almost two years I lived without a 24-70mm lens, waiting for the new and improved Canon. In the meantime, Sigma lent me their 24-70mm f2.8 pro lens to test out. I borrowed Wayne Simpson’s Canon 24-70mm Canon and spent three days in the field shooting with the two lenses. Here is what I found out:

Prices:

Canon 24-70mm f2.8L at B+H Photo = $1399.00 (weight 950g)

Sigma 24-70 f2.8 IF EX DG HSM = $899.00 (weight 790g)

The Sigma 24-70 f2.8 and the Canon 24-70mm f2.8 lenses side-by-side

As you can see from the photo above the Sigma lens is significantly smaller (and lighter) than the big Canon 24-70mm lens and the Sigma costs 40% less than the Canon lens. Can the smaller and less expensive Sigma lens hold its own in the field?

First a note on the design of the lens. The Canon lens physically gets larger when zoomed to 24mm and is shortest when zoomed to 70mm. This is a strange design feature because most lenses are physically longer at longer focal lengths like we see with the Sigma lens (see photos below).

Sigma at 24mm (left) aad Canon at 24mm (right)

At 24mm the Sigma lens is short and compact but the Canon lens is fully extended at 24mm.

The Sigma (left) and the Canon (right) at 70mm

At 70mm both lenses are the same size. Canon’s design means that the lens is larger and extends even longer at 24mm. This may seem counter-intuitive but it is actually kind of clever because the lens hood on the Canon then becomes fully functional at all focal lengths. The hood attaches to the lens body with a bayonet mount right above the red line on the lens. The hood is long and when the lens is extended to 24mm, only about 1/3rd of the hood is used. Pulled back to 70mm the full hood length is used. The Sigma lens has a short hood that is optimized for 24mm and when the lens is zoomed out, you still have a 24mm effective hood. So with the Canon you have a fully functional hood but with the Sigma it only works its best at 24mm.

So… the price you pay for the clever functional zoom within a long hood is that the Canon lens is bigger lens that weighs 20% more than the Sigma lens! If you do a lot of backlit photos then the Canon 24-70mm and its functional lens hood will better prevent flare.

A 24mm is a 24mm right?

Both the Canon and Sigma lenses are 24-70mm focal lengths so I expected both lenses to give me the exact same coverage when I swapped the lenses on the tripod-mounted body. I was surprised that with the camera in the exact same position that the two zooms gave very different angles of view at the same focal length!

The Sigma 24-70 at 24mm

The Canon 24-70 at 24mm

What the heck??? How can the two lenses both zoomed to 24mm and mounted on the same camera body on a tripod (nothing was moved) give such different coverage? Is is because the Canon extends out at 24mm and so the front of the lens is closer to the subject?

If this is the case, then at 70mm when both lenses are physically the same size then we should see the angle of view be exactly the same. But both lenses produced different coverage even at 70mm even when the camera was fixed in position on a tripod. Note how Brando the dog is slightly larger in the frame with the Canon lens.

The Sigma lens at 70mm

The Canon lens at 70mm

The Sigma gives wider angles of view than the Canon when both are set to the same focal lengths. Which one is more accurate is hard to say but for reference I tested both against my 24mm TS-E lens and the Sigma and the Canon 24mm TS-E had almost exactly the same coverage. I don’t think the Canon 24-70mm lens is truly a 24-70!

What About Close-Focus Abilities?

This one is easy, the Canon can focus significantly closer than the Sigma at both 24 and 70mm.

Sigma close-focus at 70mm (top), Canon close focus at 70mm (bottom)

But which lens is sharper at close focus? Below is the same scene at the closest focus for each lens. The camera is tripod-mounted, live view, manual focus was used, mirror lock-up and an aperture of f8 was used.

The detail close-up scene

Sigma lens at 70mm f8 (top); Canon lens at 70mm f8 (bottom)

Center sharpness (above 100% magnification in Photoshop) was similar at close focus at 70mm for the two lenses but with the nod going to the Canon 24mm F2.8L lens.

Edge sharpness at closest focus at f8 for both lenses was disappointing and both lenses suffered from fairly severe chromatic aberrations at closest focus at 70mm (see below).

Edge sharpness at f8 for the Sigma lens (top) and the Canon lens (bottom)

What about Bokeh?

Bokeh is the the aesthetic quality of the blur in the out-of-focus areas. With fast lenses like a f2.8 zoom, the quality of the blur is important as a counter point to the sharp areas. To test how each lens rendered out-of-focus areas I shot various scenes at different focal lengths all at f2.8. Below are several sample photos. For me both the Sigma and the Canon seemed to render the out-of-focus with similar pleasing blur (but I give the nod to the Sigma for softer bokeh at 24mm).

Sigma lens at 24mm f2.8

Canon lens at 24mm f2.8

Sigma at 55mm, f2.8

Canon at 57mm, f2.8

Sigma at 70mm, f2.8

Canon at 70mm, f2.8

Overall Sharpness

I tested the sharpness of both lenses using my Canon EOS-1ds Mark III. I always use Live View and manual focus to test sharpness because auto-focus can vary with various lenses and each lens needs to be micro-adjusted for precision of focus. Live View with manual focusing gives consistent sharp results.

Both lenses are optimized for sharpness in the f2.8 to f8 range. Higher apertures like f11-f22 suffer from diffraction and yield less resolution than wider apertures. For example check out the 100% magnifications of the images below. The top photo is f2.8, the middle one is f8, the final one is f22. You can see that f8 is the sharpest, f2.8 next best and f22 trails far behind in sharpness. This was true for both lenses at all focal lengths.

Canon 24-70mm lens aperture resolution; f2.8, f8, f22

At 24mm the Sigma performed better than the Canon at all apertures in both center and edge sharpness. Below are two samples the first center sharpness at f8 where there is only a minor difference between the two lenses and then edge sharpness at f8 where the Sigma does a better job.

Center sharpness at 24mm at f8, Sigma (top), Canon (bottom)

Edge Sharpness at 24 mm at f8, Sigma (top), Canon (bottom)

In tests at 35mm, 50mm and 70mm, the Canon was slightly sharper in the center and at the edges of the frame than the Sigma but not by much. At f4 both lenses performed equally at all these focal lengths. From f5.6 to f22, the Sigma was sharper than the Canon at all of these focal lengths. As well, the Canon lenses produced darker photos than the Sigma lens even when both were shot at the exact same shutter speed and aperture. The Sigma photos were lighter and a bit more contrasty.

Center sharpness at 50mm at f8, Sigma (top), Canon (bottom); both at 1/30s - note differences in angle of coverage at 50mm

Overall I give the edge in sharpness to the Sigma lens which was a better performer at 24mm and as good or better than the Canon at all other focal lengths from f4 to f22. The Canon was better at f2.8 at 35, 50 and 70mm. If you are a landscape photographer the Sigma has less diffraction than the Canon at f16 and f22.

The overall scene - Sigma at 24mm, f22

Below is a 100% magnified view of the scene above shot with the Sigma and Canon lens at 24mm and f22 — the Sigma lens handles diffraction at small aperture openings much better.

Sigma at f22 (top), Canon at f22 (bottom)

Auto-Focus Tests

Both lenses were fast and responsive in auto-focus. I could get sharper photos with both lens using manual focus and 5x Live View, but auto-focus was pretty close in sharpness. I calibrated each lens using Lens Align and micro-focus adjustments in-camera and once calibrated each lens accurately popped into focus. Neither lens seemed better nor faster than the other when it came to action photography.

©Darwin Wiggett - Sigma 24-70mm lens at 34mm, f2.8

Image Look

Both lenses produced images that looked similar. The Sigma lens produced slightly brighter and slightly more contrasty images than the Canon lens when both were shot in the same light at the same settings but overall both lenses produced crisp, sharp images.

Sigma 24-70mm lens

Canon 24-70mm lens

Final Considerations

The Canon lens has a filter size of 77mm which is common for Canon L lenses. The Sigma lens has an odd size filter thread of 82mm. If you use filters the odd size filter size on the Sigma might be a serious drawback requiring an investment in larger sized filters. For me, I use a Cokin Z-Pro Filter holder on my lenses and to get filters on the Sigma lenses was just a matter of buying an 82mm adapter ring for my filter holder. It would have been nice if the Sigma lens use 77mm threads which is a more common filter size than 82mm.

So Which One Should You Buy?

As always that depends. If you are a wedding or sports photographer who always shoots at f2.8 and likes to use back light, then I think the Canon is a good bet because it has better lens sharpness (by a small margin) at f2.8 and at all focal lengths except at 24mm. As well, the well designed lens hood/zoom mechanism on the Canon helps to prevent flare my having a more functional lens hood. Also the close focus ability of the Canon is better and sharper at 70mm than the Sigma lens and for detail photos at a wedding (rings, flowers, cake, tight face shots) this close-up capability would be welcome.

On the other hand, if you are looking for an all around travel and landscape lens, I would give the Sigma higher marks because it is smaller, lighter, sharper at 24mm and at all other focal lengths at apertures f4 and higher and it suffers less from diffraction at small f-stops (like f16 and f22). I also like that the 24mm setting on the Sigma is more true and more wide than the Canon 24mm setting. Also the Sigma lens is much less money which is always good. Both lenses seem to be robustly built and should handle the rigours of use well. Personally I prefer the mechanics and feel of the Sigma lens over the Canon lens.

Wish List

For both the Canon and Sigma lenses I wish both manufacturers made a 24-70mm lens with image stabilization (optical stabilization for Sigma). Having a stabilized lens would really help photographers get the most of a fast f2.8 lens so that we can hand-hold at lower shutter speeds. Both lenses also suffer from chromatic aberrations at the edges of the frame and are not as sharp as they could be when focused close. I expect better performance from such high end pro lenses. Overall either lens is a fine tool that will serve most photographers well. Which one you choose, depends on your interests and budget. I have no idea whether Canon or Sigma plan to update these work horse lenses but it may be worth waiting to see if they do unless you just can’t wait. Either way, you’ll get great images with these two lenses but be aware of their shortcomings.

©Darwin Wiggett - Canon 24-70mm f2.8L - great for tight close work!

©Darwin Wiggett - Sigma 24-70mm lens - great for landscape, travel and general use!

Note: I am sponsored by Sigma Canada and they provide me with lenses to use. I report things the way I see it and am not paid or influenced to bias the review. I use Sigma lenses whenever they perform better than Canon lenses. When they don’t I use Canon lenses. For my style of photography the Sigma 24-70mm lens is a better choice for me. Your mileage may vary.

Sigma 50-500mm f4.5-6.3 APO DG OS HSM Lens Review – A Field Test

Posted in Articles about Photography, Lens Review, Photography Gear, TCBlog, Videos with tags , , , , , , , , , , , , , , , , , on June 21, 2011 by Darwin

Note: To see all future reviews please note this blog is no longer active, please visit me over at oopoomoo.com

Recently Sigma Canada lent me a copy of their new 50-500mm f4.5-6.3 DG OS HSM lens to try out on my Spring Photo Tour in the Canadian Rockies. I used the lens for six days in a variety of conditions and took hundreds of photos. Here is what I thought of the big lens with the 10x zoom! Note: all sample images were made with a Canon EOS-1ds Mark III full frame camera.

The Background

Listed below are the ‘features’ of the lens that might entice someone to consider this piece of glass:

  • crazy all-in-one 10x zoom range; 50-500mm on a full frame camera or 75-750mm lens on an APS-sized camera!
  • optical stabilization feature for a 2-4 stop shutter speed advantage for hand-held photography.
  • HSM (hyper-sonic motor) for silent auto-focus.
  • low dispersion glass elements for best lens performance.
  • ‘reasonable’ price for a lens with these capabilities (approx. $1800 CAN, street price).

The Results

OK, so what’s not to like about a lens that goes from the normal point-of-view of the human eye to pinpoint telephoto images? How much zoom is 10x in the real world? The two images of the below highlight the incredible zoom range in action and show the same subject photographed from the same position (in my car) only seconds apart.

©Darwin Wiggett - Bear at 50mm with the Sigma 50-500mm lens

©Darwin Wiggett - Bear at 500mm with Sigma 50-500mm lens

During my spring photo tour I mostly used two lens; my trusty Canon 24mm TS-E (tilt-shift lens) for big wide-angle scenes and the Sigma 50-500mm lens for everything else. I loved the flexibility of the zoom range of the big Sigma lens from normal for generic landscape photography to telephoto for skittish wildlife and distant scenes. The more I used the lens, the more I liked rarely having to change lenses and the better prepared I felt for any photo opportunity! I could frame and zoom on the fly and get things I would have missed if I had to change lenses.

©Darwin Wiggett - Sigma 50-500mm at 500mm, 1/40s at f6.3

©Darwin Wiggett - Sigma 50-500mm lens at 58mm, 1/4s at f14

Besides loving the zoom range and the flexibility of the lens I also really liked the build quality and the operation of the zoom and focus rings. Best of all the lens was snappy and fast to focus and auto-focus was accurate on my 1ds Mark III. The OS (optical stabilization) worked well down for me down to about 1/60th of a second hand-held even at 500mm. I was able to walk around and photograph wildlife without a tripod and the lens seemed to grab focus the majority of the times (except in very low contrast light).

©Darwin Wiggett - Sigma 50-500 at 500mm, 1/250s at f6.3

500mm at f6.3 - detail at 100%, no post production sharpening

I also liked the ability of the lens to focus close at all focal lengths. I could make images of flowers and hummingbirds and other small subjects from a distance and nearly fill the frame. I cropped the image slightly to make a more squarish presentation but even at this distance I was not a minimum focus.

©Darwin Wiggett - Sigma 50-500mm lens at 500mm, 1/250s at f6.3

All in all the lens was a joy to use because of its crazy zoom capabilities and responsive auto-focus. I felt like I could photograph anything I could see and I certianly got images that I would not get with a kit full of prime lenses or regular zooms because the opportunity would be lost when changing lenses.

©Darwin Wiggett - Sigma 50-500mm at 413mm, 1/15s at f10

©Darwin Wiggett - Sigma 50-500mm at 167mm, 1/400s at f5.6

Ok, so the zoom range is fantastic… but what about sharpness?

Sharpness is subjective. In the end, is the sharpness of the lens going to suit your purposes? Are you selling professionally, do you make mega-big prints or will you never make anything over 12×18 inch prints? What is sharp for one person is crap for another….

When I test lenses for myself, I have a simple subjective scale for lens sharpness:

  • Excellent (the rating for sharpest lenses I have tried e.g. macro lenses or prime short telephoto lenses like an 85mm or 135mm lens). Does the tested lens match up to these levels of sharpness?
  • Very Good (good zoom lenses like a 70-200mm lens, or a prime 50mm lens would fall into this category).
  • Good (decent zooms producing professional or nearly professional quality).
  • Acceptable (good enough to make a nice 12×18 prints with a post-production sharpening)
  • Crap (Coke bottles are better than this)

Most lenses I have ever tried are normally in the good (consumer lenses like a 70-300mm f5.6) to Very Good range (pro level lenses like a 24-70mm f2.8 lens). Some lenses have sweet spots. Some lens are sharp in the center but crappy on the edges. Some zooms are better at some focal lengths than others. Some lenses are optimized for sharpness wide open while others need to be stopped down a bit for good performance. You can spend a lot of time testing every possible permutation and other sites offer this information on the web by running the lens through bench tests in the lab. But for me, I just want to know what I can get in the field with a lens and if the results give me what I need (publishable sharpness). I am lens interested in optical bench tests.

Based on my field tests making actual images in the field I would rate the sharpness of the Sigma 50-500mm lens as follows:

  • 50mm – Acceptable
  • 100mm – Good-
  • 135mm – Good
  • 200mm – Very Good
  • 300mm – Very Good
  • 400mm – Good +
  • 500mm – Good –

The lens seems to have a sweet spot for sharpness in the 200-300mm range. I found the 400mm images from the Sigma 50-500mm lens to be sharper than the 40omm images taken with a Sigma 120-400mm lens or the Canon 100-400mm lens so I would say this is a great lens to use in the 200-400mm range. I think 50-150mm  is the weakest performing range of this lens.

©Darwin Wiggett - Sigma 50-500mm lens at 332mm, 1/25s at f10

At 500mm the Sigma is decent but of course it’s nothing like a 500mm prime (I have tried the Canon 500mm f4L and would rate it as Very Good). I got publication quality photos with the Sigma 50-500mm lens at 500mm and even though it does not perform to the levels of a 500mm prime, it still gives decent results. Everything is a compromise, even if you could afford a 500mm prime ($6000-$9000 CAN) would you constantly carry the giant beast in your camera bag (over 8lbs)? With the 50-500mm it was small and light enough that I actually had the lens with me all the time and got shots at 500mm that I would have missed if I owned a 500mm prime (because I would have left the lens in the car). Sharpness is the be-all for some photographers, but having a great shot that is a little softer but useable is better than having no shot at all!

©Darwin Wiggett - Sigma 50-500mm at 500mm, 1/25s at f10

©Darwin Wiggett - Sigma 50-500 at 450mm, 1/640s at f7.1

The Dislikes:

No lens is perfect and the 50-500mm lens has some flaws that may make or break it for you:

  • 95mm front lens element means the lens is hard to filter. I managed to use a polarizer and ND filters by using a Cokin Z-Pro Holder and a Cokin Z-Pro 95mm adapter ring but using filters on this lens will cost you big bucks to buy Z-Pro or Lee sized filters. This is not an easy lens to filter.
  • if you use 1.4, 1.7 or 2x extenders you will not be able to auto-focus your lens (manual focus only). I would not recommend extenders for this lens as sharpness suffers to non-acceptable levels. Plus who needs an extender when you got this much zoom range?
  • the lens is less contrasty than Canon or Nikon lenses and sometimes the colours seem a bit flat (but for me that was an  easy fix in  JPEG camera settings or in RAW conversions).
  • when I use live view and manual focus I love it when the lens stays sharply focused no matter what focal length I zoom to (like my Sigma 120-400mm lens does) – the 50-500mm lens needs to be refocused every time you change the zoom setting (frustrating for the way I shoot). But when auto-focus is used, the lens is zippy and so refocusing is less of a chore.
  • the weight and bulk turns some people off but it is only a tad bigger than the Canon 100-400mm lens and for what you get I think the lens is actually surprisingly small.
  • like all big lenses, to get optical sharpness requires precision in technique – this lens requires a super robust and sturdy tripod for any shots less than 1/60th or 1/125th of a second. People might complain that this lens is not sharp but chances are good it’s an inadequate tripod problem and not a problem with the lens! For longer shutter speeds, 1/30th of a second or longer,  mirror lock-up and a remote release are a must! It is difficult to get a sharp shot with this lens at slow shutter speeds unless you are using proper technique and have a super solid tripod and tripod head.
  • this lens (and many super long lenses) doesn’t do great with distant subjects; atmospheric haze, heat shimmers and other atmospheric effects can reduce apparent sharpness in long lenses and long zoom settings; realize this is not a issue with this lens but is a a long telephoto issue in general.
  • the lens vignettes (slight darkening of corners) at all focal lengths in apertures from f4.5 to about f9.0. I don’t mind this because I often purposefully add vignetting to my photos in post because I like the effect (the vignetting can easily be fixed in Camera RAW). But some people demand and need even exposures across the frame.
  • the lens does suffer from fringing at the edges of the frame with full-frame cameras when the lens is in the 50-150mm range and shot in contrasty light (this can easily be corrected in Camera RAW in Photoshop or Lightroom). If you plan to shoot JPEGS and do not want to spend time correcting fringing, then this lens might be problematic for you.
  • edge sharpness on full frame cameras is about one quality factor from center sharpness (but this is common with most lenses).  On APS-sized sensors both edge vignetting and edge sharpness concerns disappear because of the crop factor of the camera.

©Darwin Wiggett - Sigma 50-500mm at 450mm with a Cokin P173 Blue-Yellow polarizer, 1/4s at f16

Below is an image shot at 50mm with the Sigma 50-500mm lens and the image that follows shows the fringing at the edge of the frame in contrasty light.

©Darwin Wiggett - Sigma 50-500mm lens at 50mm, 1/1600s at f10

Colour fringing at the edges of the frame at 50mm with the Sigma 50-500mm lens

Conclusion

I was super skeptical about this lens. Any lens with a 10X zoom range I am ready to write off as crappy in terms of image quality. I told Sigma I would test it but that they should be prepared for a completely honest review. I was prepared to pan this lens. But I was wrong.

Sure the lens is not as sharp as a 300 or 500mm prime lens, but who would expect it to be? I was surprised by how good this lens actually was especially in the 200-400mm range. It was decent at 500mm and yields publication quality images (with a little help from post-production sharpening). The weak spot in the lens is the 50-150mm range where sharpness and fringing are problems that need to be fixed in post-processing. Also this lens needs to be used with proper techniques to yield optimal results.

©Darwin Wiggett - Sigma 50-500 at 244mm, 1/30s at f13

The one thing that caught me off guard is how much I loved the zoom range and how I felt I was ready to capture any subject from intimate details, to landscapes both grand and extractive, to wildlife all with one lens. I got addicted to having one do it all (and more) lens on my camera. How liberating! And surprisingly I found that long lens settings in the 400-500mm range made up the vast majority of my landscape work with this lens.

If I was going on a trip that was a combination of generic nature photography where I might expect grand landscapes, wildlife and intimate details, then I would be tempted to take just two lenses; a 24-70mm f2.8 and the 50-500mm lens. Two lens and I am covered for every possibility! In fact next year I am going to Iceland and these two lenses might be my perfect travel companions.

©Darwin Wiggett - Sigma 50-500mm lens at 167mm, 1/60s at f5.6

The Dilemma

Sigma lenses are made to fit Canon, Nikon, Pentax, Sony, and Sigma cameras so if you have one of these camera systems, then you might consider the Sigma 50-500mm lens. The problem is Sigma makes a few long range telephotos to choose from and so your choices become a bit difficult:

Sigma 50-500 f4.5-6.3 – reviewed above ($1800 CAN)

Sigma 150-500mm lens f5-6.3 – (street price $1200 CAN)

Sigma 120-400mm lens f4.5-5.6 – see my review here (street price $1000 CAN)

Which one to buy?? It all depends on what you own already, your needs, your photographic subjects etc. I bought the 120-400mm lens after I reviewed it because I liked it better than Canon’s 100-400mm lens and I liked that I could filter the lens easily (77mm filters which I already own). Plus I already have a 70-200mm lens. That choice made sense for me. Look at the specs of each of these lenses and check out several reviews to decide if any of these lenses shoot your shooting style and budget.

For an all round nature shooting I would be happy with either the 50-500 or the 120-400mm lenses. I have not used the 150-500mm lens. If I planned to be a wildlife specialist, I would save up my coin for a fast prime lens (300mm f2.8, 500mm f4 or a 200-400mm f4 or Sigma’s new 120-300 f2.8) but all of these these lenses are very expensive and very heavy. There is no perfect lens but with a little research you can find one that is a good match for you. Good luck!

Full disclosure: I am sponsored by Sigma Canada. I give fully honest reviews of what I think but for some people the issue of ‘sponsorship’ might colour their view of this review. I only accept sponsorship from companies where I am allowed to say whatever I think, Sigma Canada allows this. If you buy from B+H Photo I will get a small percent of the sale that helps support this website.

If you want to buy the 50-500mm lens in the USA I recommend B+H Photo (good service and prices and they support this website) and for Canadian customers please support The Camera Store – the best place to buy any camera stuff in Canada (a biased but honest opinion!).

I hope this field review has been useful. Feel free to comment but keep things polite and reasoned and offer useful input that will help others make informed decisions. Name-calling, thoughtless comments or personal attacks on anyone will not be tolerated and those comments will be removed. Play nice!

©Darwin Wiggett - Sigma 50-500 at 167mm, 1/4s at f13

©Darwin Wiggett - Sigma 50-500 at 167mm, 1/10s at f10

©Darwin Wiggett - Sigma 50-500mm lens at 500mm, 1/250s at f6.3

Sigma 17-50mm f2.8 vs Canon 17-55mm f2.8 and Tamron 17-50mm f2.8

Posted in Lens Review, Photography Gear, TCBlog with tags , , , , , , , , , , , , , on May 9, 2011 by Darwin

On full frame cameras the 24-70mm f2.8 lens is the go-to lens for travel, sports, wedding, street, and landscape photography. On cropped sensor cameras the equivalent focal length to a 24-70mm is roughly 17-50mm. This latter focal length gives you wide, normal and telephoto lens perspectives in a relatively small package that fits on cropped sensor cameras. If you are looking for a fast all-purpose lens for your Canon camera whether a Rebel, 20D, 30D 40D, 50D, 60D or the 7D, then you have four choices:

Note: To see all future reviews please note this blog is no longer active, please visit me over at oopoomoo.com

Canon EF-S 17-55 f2.8 IS USM

  • Image Stabilized
  • Ultrasonic lens (no focus noise)
  • UD glass
  • internal focus
  • close focus 0.35m
  • filter size 77mm
  • weight 645g
  • cost $1200 CAN

Sigma 17-50mm f2.8 EX DC HSM OS

  • optical stabilized
  • hypersonic motor motor (HSM) – no focus noise
  • internal focus
  • two low dispersion FLD glass elements
  • close-focus 0.28m
  • filter size 77mm
  • weight 565g
  • cost $775 CAN

Tamron 17-50mm f2.8 XR Di II VC

  • vibration compensation
  • LD (low dispersion) glass
  • internal focus
  • close-focus 0.29m
  • filter size 72mm
  • weight 570g
  • cost $579 CAN for the VC version and $450 CAN for the non VC version

There is also the Tokina 16-50mm AT-X 165 Pro Dx but I did not have an opportunity to test this lens.

A Bit of History

When I picked up my first cropped sensor Canon camera (a Rebel Xsi) I wanted a light, fast lens for hiking and backpacking. I tested out the Tamron 17-50mm lens (the f2.8 XR di II LD versionwithout the vibration compensation feature). I found it to be surprisingly sharp and I picked up a new one for a sale price of $350 CAN! It was perfect for landscape photography especially for me because I almost always use live view and manual focus on the Rebel to make landscape images. I owned the lens for a year or so and took many landscape photos with it in all sorts of conditions. It was a super performer for the price! But… be aware that the Tamron  lens is really lacking as an auto-focus lens. It was painfully slow to focus and was noisy when focusing. I tried using it with dogs and sports and it was not really suited for action photography.

©Darwin Wiggett - Tamron 17-50 f2.8 lens

©Darwin Wiggett - Tamron 17-50mm f2.8 lens

And Then…

Sigma sent me their 17-50mm f2.8 lens to try it. I was incredibly happy with the Tamron in terms of sharpness and so my first tests were to see if my budget priced Tamron was as sharp as the more expensive Sigma lens. I did the standard tests in the studio using a lens chart to check sharpness at all apertures and at various focal lengths. And then I took the lenses out in the field and photographed the typical kinds of subjects that I shoot to see how the lenses performed in terms of contrast (snap) and colour rendition and also things like flare control and distortion. Rather than bombard you the reader with tons of detailed comparison shots the conclusion of all these tests was the same. Both lenses performed the same optically but with the nod going to the Tamron in the 17-35mm range at f2.8 (better edge sharpness).

©Darwin Wiggett - Sigma 17-50mm lens at f14

But… the Tamron was terrible auto-focus performer! I’ve found that using live view at 5x magnification and manually focusing lenses gives me much sharper images than using auto-focus even in bright contrasty light. This result is consistent across cameras I have tried from the Canon 1ds Mark III, Canon Rebel Xsi and Rebel T2i, Canon 60D, Canon 7D and the Nikon D300s. On workshops and tours I often illustrate this to participants using their own cameras. To try it yourself, simply set your camera to aperture priority and use the smallest number on your aperture dial like f2.8. Use the center focus point on your camera and let the camera focus on a contrasty part of the subject. Now go into live view and magnify the area (e.g. 5x) where the camera auto-focused.  Switch your lens to manual focus and adjust the focus to see if you can get the image sharper than the auto-focus. Often you can easily improve on the sharpness. Check out the scene below. I had the Canon Rebel Xsi mounted on a tripod and the auto-focus was set to ‘one shot’ with the center focus point selected. I had the aperture set to f2.8 and let the camera auto-focus. Then I rephotographed the same scene using manual focus in live view.

The auto-focus test scene

Below are the results of the test using the Sigma 17-50mm lens at f2.8. The image is magnified to 100% view. The top photo is auto-focus, the bottom is manual focus in live view.

Sigma 17-50 at f2.8: top=auto-focus, bottom=manual focus in live view

The auto-focus on the Sigma/Rebel combo locked in really well. The manual focus is a tad sharper but not by much. Below are the results of the Tamron lens on the Rebel Xsi:

Tamron 17-50 f2.8: top=auto-focus, bottom=manual focus in live view

What can you say? The auto-focus on the Tamron lens is terrible! It is slow, it searches, it hunts, it creeps, it’s noisy. I have tested and tried several Tamron lenses (from their 70-200 f2.8 to their 10-24mm lens) and the problem is the same. If, like me, you mostly use manual focus and a tripod, then the Tamron is easily the best buy of the group (especially the non VC version of the lens) and optical performance is really fine. But if you want a sports, travel, portrait lens where you can rely on auto-focus, then I would pass on the Tamron. Also note I did not test the vibration compensation (VC version) of this lens, other reports on the web suggest that sharpness of the VC version is lower than the non VC version. Test before buying!

And so, after testing the Sigma 17-50 f2.8 against the Tamron lens, I decided to sell the Tamron and keep the Sigma. The Sigma was just as good optically (except at f2.8 where edge sharpness was lower) but it had fast and accurate auto-focus and it had optical stabilization for hand-held shots.

And So What About the Canon 17-55mm f2.8?

This is Canon’s flagship lens for cropped sensor cameras and numerous reports state that this lens is super sharp and an all around great performer but it comes at a high price ($1200 CAN). Is the overall quality and performance of the Canon worth the extra cost (more than $400) over the Sigma?

I took the two lenses out over a weekend and ran them through a few tests such as:

  1. Optical performance (sharpness, vignetting, flare etc.)
  2. Auto-focus tests
  3. Image stabilization tests
  4. Close-focus capabilities

Here is what I found:

Optical Performance

I compared the sharpness of both the Sigma and the Canon lenses using manual focus in Live View. When precisely focused I really could not give the nod to one lens over the other when it came to center sharpness at all focal lengths and apertures. But at f2.8 in the focal range of 17 to 35mm the Canon had significantly better edge sharpness than the Sigma.

Edge sharpness at 17mm at f2.8 (Sigma top, Canon bottom)

It’s easy to see here that the Canon lens is really good wide open even at the edges. The Sigma lens does not match the edge performance of the Canon until stopped down to f8! After f8 the two lenses perform equally well.

Another weakness of the Sigma Lens are fringing artifacts at the edges of the frame when the lens is shot from 17- 35mm in high contrast light. The Canon also suffers these effects but to a lesser extent.

Edge fringing at f2.8 at 17mm - Canon top, Sigma bottom

The fringing on both lenses is more controlled and equal once the lenses are zoomed out to 35mm or higher.

The Canon lens appears to be optimized for best performance in the aperture range from f2.8 to f8. Images at f11 are decent but less sharp overall and images at f16 or higher are terrible!

Canon 17-55 at f5.6 (top) and f22 (bottom)

I found that although center sharpness on the Sigma is as good as the Canon at f2.8 and f4 that overall image sharpness from edge to edge is best with the Sigma in the f5.6 to f11 range with good performance up to f16. The Sigma is better than the Canon in the f11 to f16 range and therefore is a better choice for landscape work requiring large depth-of-field.

Sigma lens at f16 top photo, Canon lens at f16 bottom photo

The Sigma lens also records images with more contrast and ‘pop’ and with a more accurate colour cast than the Canon lens which tends to record scenes flat and washed out and cool in colour tone.

Sigma lens top photo, Canon lens bottom photo

Sigma lens top photo, Canon lens bottom photo

In numerous tests I found this same difference in contrast and colour between the two lenses. All comparisons were shot at the same exposures, white balance etc. The Sigma lens simply had a more pleasing rendition of scenes for my tastes.

As far as flare is concerned it depends. Sometimes the Sigma gave more flare (e.g. at 17mm) sometimes the Canon was more prone to flare (e.g. at 28mm).

Auto Focus Tests

I tested both the Sigma and the Canon lens for accuracy of auto-focus vs manual focus in live view and both lenses returned similar results. Live view gave slightly better results for both lenses. Only in dim light did the auto-focus capabilities start to falter.

With action sequences of people running, cars on the highway and moving dogs, I saw absolutely no difference in the ability of the Sigma and Canon lenses to track focus. As well, with static subjects both lens were zippy and fast to auto-focus and for me they seemed matched in their abilities.

Image Stabilization Tests

Handheld images using auto-focus and image stabilization (Canon) and optical stabilization (Sigma) returned fairly similar results but I got a slightly higher percentage of sharp shots in the 1/15th to 1/30s range with the Canon lens. So nods in this department to Canon.

Close-focus Capabilities

The clear winner in this category is the Sigma lens. Not only does it focus closer (see images below) but when photographing close subjects (e.g. head and shoulders or closer, the Sigma is significantly sharper at all apertures than the Canon lens. The Canon does not seem to like close subjects and optical performance really suffers. This is not a good lens to use for close-up work!

sigma at closest focus at 50mm

Canon closest focus at 55mm

Sigma close detail sharpness at f8

Canon close detail sharpness at f8

Conclusion

Which lens you choose all depends on your budget and on your needs. If want the best overall optical performance for your dollar then the  Tamron SP AF17-50 f2.8 Xr Di II is a fantastic buy! Although I did not this test the lens directly against the Canon lens, I think it is just as sharp at all apertures but it costs almost 1/3rd the price of the Canon lens! But the Tamron is not a lens to buy if you rely on auto-focus. This is a good landscape lens when used on a tripod and focused manually in live view. But do not try action photos with this lens or you’ll be disappointed.

If you want a lens with good all around performance at the a reasonable price, then the Sigma 17-50mm f2.8 lens might be the lens for you. The Sigma is as good as the Canon lens in terms of auto-focus, it’s a sharp as the Canon lens when stopped down to at least f5.6 and it is a much, much better lens for close-up subjects. As well the contrast on the Sigma lens is snappy and the colour rendition is accurate. The Sigma is a better landscape lens than the Canon because it has better performance in the f11-f16 range which are apertures often needed for depth-of-field. Also the lens is the lightest of the bunch. I would recommend this lens for nature and generic photography.

If you want to photograph people, sports, or action or hand-held street photography where  wide apertures like f2.8 or f4 are regularly used then the Canon 17-55 f2.8 lens lens is the best choice. It’s sharp edge-to-edge when wide open (with little fringing), has great image stabilization and zippy auto-focus. The drawbacks are its heavier weight, poor close-focus performance, flat contrast and cool colour rendition and large price tag.

In short, none of these lenses are perfect but some work better for some purposes than others. As always try before you buy but hopefully this review will help narrow your choices.


©Darwin Wiggett - Sigma 17-50mm lens at f11


Sigma 85mm f1.4 vs Canon 85mm f1.2L II

Posted in Camera Review, Event Photography, Good News, Lens Review, Photography Gear, TCBlog, Techniques with tags , , , , , , , , , on April 12, 2011 by Darwin

Note: To see all future reviews please note this blog is no longer active, please visit me over at oopoomoo.com

Sigma Canada gave me their new 85mm f1.4 lens to review. I thought it would be a cool lens to use on my dog portraits and maybe for street photography but I have been so busy with landscape shooting that I have not had time to give the lens a serious spin nor a detailed review.  So… to solve the problem I am letting someone more qualified to do the review for me (smart eh?) and share his findings here.

My good friend Wayne Simpson is a full-time portrait, wedding and landscape photographer who owns and uses the coveted Canon 85mm f1.2L lens daily in his work. I thought Wayne was the perfect guy to give the Sigma a test run and see how it performed for a working photographer. Both the Sigma and the Canon 85mm lenses are designed for portrait, sports, event and wedding photographers where prime lens performance (a fast wide aperture) is needed either for low light shooting or for an ultra-thin slice of focus. Wayne was interested in just how well the Sigma could stand up to his much lauded Canon 85mm. So I gave the lens to Wayne and he played… here is his report and results:

Note, neither I, nor Sigma Canada have sponsored, paid nor bribed Wayne… not even with beer! I simply wanted Wayne’s honest impressions as a working photographer. Wayne receives no cut, no commissions on sales, and not even a ball cap for his review (not too smart eh?). Wayne just wanted to see how both lenses performed so that he had the best choice for his own work. Plus like any guy, he likes to play with toys – can you blame him?!


Sigma 85mm f1.4 EX DG HSMprice $969 US at B+H Photo

image from Sigma Canada – available in Canada at The Camera Store

Canon EF 85mm F1.2L II – price $2149 US at B+H Photo

image from The-Digital-Picture.com

available in Canada at The Camera Store

Wayne Simpson reviews the Sigma 85mm f1.4 vs the Canon 85mm f1.2L II

Okay, first the disclaimer:

This is a practical comparison, and by no means scientific in any way. The following is simply my opinion as a working wedding and portrait photographer.

All shots are done with a Canon 1D Mark IV. The only adjustment done to the images is the odd exposure adjustment to the  RAW image, however, any images being compared will have had the exact same adjustments. White balance was either set to daylight or cloudy and was not changed after capture.

Here we go…

When I heard about the new Sigma 85 1.4 I must admit that I was curious, but  never really considered it as an option over my Canon 85 1.2 II. Even when the opportunity came to take the lens for a test drive I was not overly excited, but decided to give it a whirl. Well, once I had the lens in my hands I could immediately tell that this lens is for real!

Lets have a look at the build quality…

While I love the build quality of my beloved Canon 85 1.2 II, the Sigma appears just as good… just different. The actual diameter of the Canon (especially the lens hood) is much larger than the Sigma. I have always found it annoying that my Canon 85mm is big lens and it never seems to fit comfortably into any of the bags I have tried. This always  slows me down when changing lenses. The awkward size of the Canon prevents me from carrying as many lenses as I would like since this beast seems to take up the space of one and a half  “normal sized” lenses. This would not be an issue with the Sigma which is significantly more compact.

I tend not to use manual focus very often with my Canon because I don’t feel confident with its incredibly loose and touchy focus ring. The Sigma focus ring is more snug and less touchy which inspires confidence especially to use manual focus. However, the AF/M switch on the Sigma seems a little too exposed and prone to being bumped out of place; however it never happened to me while using it.

When shooting in bright light and using flash, I often like to use screw-on neutral density filters to cut down the light and maintain my sync speed while shooting at wide apertures. As a Canon shooter with other L series lenses, I have come to expect the filter diameter to be 77 mm.  However the Canon 85 1.2 II uses a 72mm filter size. I was happy to find that the Sigma uses the popular 77 mm size, which may save you money on filters especially if you already own other Canon L-series lenses!

If you have ever used the Canon 85 1.2 II you know how careful one needs to be when changing lenses. The rear element is basically level with the lens mount, which is a little scary. As if that wasn’t scary enough, Canon has hidden the red dot to align the lens and mount so that it’s not easily visible when changing lenses. Again, these issues don’t exist with the Sigma.

So it’s built well, but how well does it autofocus?…

Very well actually! I would guess that the Sigma is about twice as fast as the Canon in decent light. After using my Canon 85 1.2 II for a few years now, I have come to accept the fact that it is very slow to focus. In fact, if I’m photographing kids, or anything moving I will reach for my Canon 70-200 f2.8L lens instead. I missed many, many shots due to slow auto-focus before I learned the limits of the lens. While I did not test the Sigma on any moving subjects, I can confidently say that it would beat the Canon hands down when tracking a moving subject.

In backlit situations, the auto-focus of both lenses go a little crazy. At first it seemed that the Sigma reacted worse, however I think it just seems that way because the auto-focus bounces around faster!

Next, I tried the two lenses in a dark room shooting at f1.4, ISO 6400 at 100/sec (very dark). In this situation (without focus assist or flash) the lenses seem to focus almost the same speed on my 1D Mark IV, with a slight edge going to the Sigma. The Sigma seems to lock focus a little faster and with a bit more authority than the Canon. The one thing that the Canon has over the Sigma in this situation is that it can open up to f 1.2 allowing you faster shutter speeds for hand held shooting. This can potentially save your bacon as long as you can lock focus in the first place!

So, can the Sigma compete with the image quality of the legendary Canon 85 1.2 II?…

In short, yup! As you will see in the images below, it’s pretty much impossible to tell which lens is which when looking at image sharpness and bokeh. You don’t really see much of a difference until you look at the colour and brightness. Originally I thought that the difference in colour might be due to using an automated white balance (daylight or cloudy) and that the camera might be compensating somehow because of one lens having a larger maximum aperture than the other. Keeping this in mind I quickly set a manual white balance and re-shot, but found the same shift in colour.

©Wayne Simpson - The sharpness test subject

©Wayne Simpson - Sigma 85mm f1.4 at f4

©Wayne Simpson - Canon 85mm f1.2L II at f4

©Wayne Simpson - Sigma 85mm f1.4 at f1.4 - Bokeh test

©Wayne Simpson - Canon 85mm f1.2L II at f1.4 - Bokeh Test

©Wayne Simpson - Sigma 85mm f1.4 - Colour

©Wayne Simpson - Canon 85mm f1.2L II - Colour

One thing that is pretty much inevitable when shooting at very wide apertures is some amount of chromatic aberration or fringing. Now I’m no scientist, so I can’t explain exactly what causes it, but I do know that I don’t like it and it can be difficult to fix in post production (for me anyways!). In scenes with little contrast I found that both lenses where acceptable by my standards – even at f 1.4. Once you enter a high contrast scene however, the story changes. I found that the Sigma needed to be stopped down to about f 2.8 to eliminate the fringing, while the Canon still had a tiny bit of fringing still visible at f 2.8, although very minor. At f2.8 the sharpness is absolutely incredible with both lenses! I honestly can’t say which one is sharper, which is amazing considering there is something like a $1000 dollar difference in price!

©Wayne Simpson - fringing in low contrast light, Sigma 85mm at f1.4

©Wayne Simpson - the high contrast test for fringing

©Wayne Simpson - Sigma 85mm f1.4 at f1.4 showing fringing

©Wayne Simpson - Canon 85mm f1.2L at f1.4 showing fringing

So, lets sum up the pluses and the minuses for the Sigma…

The pluses:

–          faster auto-focus

–          77mm filter diameter

–          rear element is not dangerously exposed

–          slightly better focusing in low light

–          much less expensive

–          lighter and more compact

The minuses:

–          does not open to f 1.2

–          slightly warm colour cast which means extra work in post to match the colours of othere Canon lenses

–          darker exposure and a little less ‘pop’ than the Canon lens

–          Exposed AF/M switch can be dislodged accidentally

So, would I sell my Canon 85 1.2 II and buy the Sigma 85 1.4?…

Heck, it’s not out of the question! I guess the real question is do I really need to shoot at f 1.2, and do I need the faster autofocus offered by the Sigma? I have had the odd occasion where shooting at f 1.2 has saved me, but they are very few and far between–-I’m guessing I could live without it. The faster auto-focus though would be a very, very welcome change from my slower  Canon 85mm f1.2.

The major problem for me however, is the warm colour cast (visible in the comparisons)the  and slightly darker images  produced with the Sigma lens. I realize that these can both be fixed in post production, however it would mean that I would have one lens that produces a different colour than all of my other lenses. which means lost time in image correction. The images from my Canon just seem to have that tiny bit more pop to them… I don’t know how else to explain it! Maybe it’s something to do with the amount of money I spent on the  Canon lens, or maybe I’m still having a hard time accepting the fact that the Sigma is almost identical for about half the price!

If you are looking to buy one of these two lenses, my official advice is … go for the Sigma. For the difference in price, it is definitely the best bang for your buck. I will likely end up holding on to my Canon. However if I could do it again I would likely choose the Sigma especially for its zippy auto-focus. Unless you shot the two side-by-side, you likely would never notice a difference in the images. Who would have thought that this lens could hold it’s own against the legendary Canon 85 1.2 II!

Other reviews of these lenses:

Sigma 85mm f1.4L – dslrphoto.com summarizes numerous reviews here

Canon 85mm f1.2L II – Photo Zone review, The Digital Picture Review

See also the latest issue of Popular Photography for further comparisons

©Wayne Simpson - Sigma 85mm f1.4 at f1.6


Field Test – Sigma AF 8-16mm f/4.5-5.6 DC HSM

Posted in Photography Gear, TCBlog, Techniques with tags , , , , , , , , on June 29, 2010 by Darwin

Note: To see all future reviews please note this blog is no longer active, please visit me over at oopoomoo.com

I was lucky enough to be able to test Sigma’s new 8-16mm ultra-wide rectilinear zoom prior and during the recent Extreme Saskatchewan tour.  If you want rigorous lab tests of this lens’ performance I recommend PhotoZone and LensTip. Below are my impressions of the lens from shooting landscape images in the field—no lens test charts were harmed in the making of this blog entry!

Background

The Sigma 8-16mm lens (12-24mm equivalent on a full-frame camera) is specifically made for APS-C sized cameras and is available in Nikon, Canon, Sony, Sigma, and Pentax mounts. At 8mm, the angle of view is a whopping 119 degrees–that is wide! For  the full specs on this lens refer to the Sigma Website but in short this lens is the widest zoom currently on the market and has special FLD glass for reduced chromatic aberrations (you know to get rid of those nasty coloured edges along lines of high contrast). The spiffy glass goodies and tough build are meant to give pro quality images. Supposedly this lens delivers  punchy, sharp images in an extreme wide-angle zoom. Can it deliver?

Sigma's 8-16mm lens on a Canon Rebel

First Impressions

The lens is solidly built with a wonderfully smooth feeling manual focus and zoom mechanism. But the real surprise occurs after you take off the lens cap and the protective lens tube–it is crazy just how wide 8mm is… the whole world expands before you! This is a fun lens that demands you go out and play with its severe angles of view. Of course because of its bulging front element you can not filter this lens. But when you are this wide, things like polarizing filters are pointless unless you enjoy uneven splotches of polarized light across the wide scene. In scenes where I had a bright sky and a dark foreground I did miss being able to use a grad filter but that problem can be fixed by making several exposures and blending them together in post-production.

Results

I was impressed! The lens was very sharp even wide open and across all focal lengths. Mostly I was blown away by how sharp the lens was at 8mm even on the edges and especially at the apertures of f4.5 to f8. Also I was pleased by how little chromatic aberration I saw and how well the lens handled flare in backlit situations. I found I almost always used the lens at 8mm for extreme views and it was really nice that the lens performed so well even at its widest focal length.

I found that this lens performed best at all focal lengths at an aperture of f8 which gave great overall sharpness from center to edge and also gave the most even exposure across the frame. With APS-C cameras, small apertures such as f16 and f22 cause much diffraction and image quality suffers. With the two Canon Rebels I used (XSi and T2i) this lens gave image results that were of high quality at f11 but at f16 and f22 image sharpness suffered greatly. Frankly performance at f22 was really bad. I recommend using apertures of f11 or less with this lens. I always seemed to have enough depth-of-field even when limited to f11 with this lens so don’t let the limit of usable apertures worry you much.

©Darwin Wiggett - Sigma 8-16mm at 12mm

What I liked most about the lens was how I could use the extreme wide angle to let me get it all in. I also liked to be able to exaggerate perspective and to create fresh and exciting viewpoints. I think this is a great landscape or travel lens that opens up worlds of creative possibilities. I sure had fun using the lens and I got some memorable images. As a final note if you have video capabilities on your camera you can make some crazy fun videos at 8mm! Below are a few more images I took with the lens–all I can say is each photo is sharp from edge to edge which really makes me happy because most wide angle lenses I have tried have not performed this good!

BTW if you want a chance to win this lens be sure to enter the Travel Photo Contest on this blog And thanks especially to Gentec who supplied a review lens and who graciously has offered a brand new 8-16mm lens as the grand prize in the photo contest!

©Darwin Wiggett - Sigma 8-16mm at 16mm

©Darwin Wiggett - Sigma 8-16mm at 9mm

©Darwin Wiggett - Sigma 8-16mm at 8mm

©Darwin Wiggett - Sigma 8-16mm at 8mm

©Darwin Wiggett - Sigma 8-16mm at 8mm

©Darwin Wiggett - Sigma 8-16mm at 8mm

©Darwin Wiggett - Sigma 8-16mm at 8mm

Lens Review: The Sigma 120-400 4.5-5.6 APO HSM Telephoto Zoom

Posted in Photography Gear, Techniques with tags , , , , , , , , , on February 23, 2010 by Darwin

First the preamble:

I am a working landscape photographer. I am not a lab technician. I do tests in field conditions shooting with the gear just like I normally do. I do not take photos of lens charts or do studio tests. I want to know how well a lens or camera works in the field. I am not paid to do these reviews nor do I get a kick back for any sales of products reviewed. I do not get free camera equipment nor am I sponsored by any camera or lens manufacturers. I am only interested in finding decent gear at a fair price. When I do find a ‘good buy’ I will share my findings with others and then you can decide if the gear will be a good fit for your shooting style.

Note: To see all future reviews please note this blog is no longer active, please visit me over at oopoomoo.com

The Backgound

Anyone familar with my work knows I use Canon cameras and Canon Tilt-Shift lenses for the majority of my landscape work. Overall I am pretty happy with the gear I use and when I am not I freely express what I think are the short-comings of the gear (which probably has not made Canon happy at times).  🙂

What is less well known is that I love telephoto zooms to create ‘extractive landscapes’ (like the one below). I carry a little Canon 70-200 f4L lens in my pack and a Canon 300mm F4L IS lens to cover my telephoto needs. When the 70-200mm does not supply enough reach, I switch to the 300mm. I am happy with these two Canon lenses but sometimes I wish I had all that zoom range in one lens. So I thought I would test the Sigma 120-400mm lens. I chose this lens for it useful focal range, the fact that it accepts 77mm filters (I love filters!), the fact that it is not too crazy heavy (1750 grams) and the fact that it is affordable (about $1000 CAN). I also compared it to Canon’s 100-400 f4.5-5.6L lens which I used to own but sold because I was not a huge fan of the lens (but maybe that was a mistake–we’ll see).

©Darwin Wiggett

The Procedure

In the field I used a solid Gitzo tripod and a Really Right Stuff BH-55 ball head to support the camera and lenses. I used mirror lock-up, a cable release, no filters, and used live view to focus. I have tested my Canon EOS-1ds Mark III extensively and I get sharper photos using Live View at 10x magnification than I can get with the camera using auto-focus even after focus calibration . I also turned off Optical Stabilization (Sigma) and Image Stabilization (Canon) for all tripod shots. I shot near and distant scenes. Here are my findings:

The Lenses Tested

The lenses compared from left to right:

Sigma 120-400 4.5-5.6 APO, Canon 100-400 f4.5-5.6L, Canon 70-200 F4L and Canon 300mm F4L

First Impressions

I was impressed by the build quality and handling of the Sigma lens. It felt sturdy, and the focus and the zoom mechanisms were smooth and silky. The lens did not feel ‘cheap’ or clunky in any way. The zoom ring is at the front of the lens and a half twist of the hand takes you quickly from 120 to 400mm. Most Canon lenses have the focus ring in the front of the lens and the zoom ring behind so it took me some time to get used to having the opposite arrangement with the Sigma lens. The Canon 100-400 lens has a push-pull zoom that also takes a little getting used to. People that own the 100-400 either love or hate that push-pull zoom, few people are neutral about it. Sigma’s rotating zoom is probably more acceptable to a wider audience.

The Sigma 120-400 and the Canon 100-400 zoomed out to 400mm

An interesting note about the Canon 100-400mm. Numerous photographers I know refer to the Canon lens as the Vacuum Cleaner. Take the back lens cap off the 100-400 and cup your hand over the rear lens element. Now push and pull the zoom back-and-forth. You’ll get a good stong flow of air sucking in and out of the lens. Guess what moving air attracts? Dust. A fairly common complaint with the Canon 100-400mm lens is that it is a big dust sucker leaving you with a dirty camera sensor. I tried the same test with the Sigma lens and there is still airflow while zooming but significantly less than with the push-pull Canon Lens. If you want to vacuum your carpet as well as take photos, then the Canon 100-400 might be a good choice 🙂

Sharpness Tests

I compared all the lenses at every aperture and at numerous overlapping focal lengths. Rather than bore you with pages and pages of 100% screen captures just let me summarize my findings below. You’ll need to take a leap of faith that I did my best to make the field comparisons as fair as possible and to keep shooting conditions as controlled as I could. I repeated the tests three times to confirm my initial findings. I will include a couple of critial comparison for visual reference. Also I will let you know about my preconceptions before the test so you know what I expected to find (my bias). I assumed that the 70-200 f4L and the prime 300 f4L would outperform both the Canon 100-400 and the Sigma 120-400. Also I expected the two big zooms would probably be close in quality.

Sharpness and Aperture

Lenses all tend to have a sweet spot where there are one or two apertures that give the best resolution or sharpness performance. All four of the lenses tested here had the best sharpness at apertures of f5.6 to f11 with f8 being the sweet spot for all the lenses at all focal lengths. For example, I photographed the image below with the Sigma 120-400 at 200mm.

Shot with the Sigma 120-400 lens at 200mm

 In the 100% magnified view of the same scene you can clearly see that apertures larger than f11 start to lose edge sharpness.

100% view of Sigma 100-200 at 200mm based on aperture

All of the Canon lenses used in this test had a minimum aperture of f32. I would happily use any aperture on any of these lenses from wide open to f11. Even f16 was acceptable in most cases. But f22 and especially f32 are useless apertures in my opinion due to loss of sharpness through diffraction. Below is a 100% view of a photo of a fence in my backyard showing a comparison of f11 and f32 using the Canon 100-400mm lens at 200mm – the differenes are striking. I repeated this test three times in different light and with all the Canon lenses–in the end I found that  f22 and 32 are useless if you want pro caliber results and/or the capabilities to make large prints.

Canon 100-400 at 200mm

Vignetting

Often zoom lenses will show some uneven exposure across the frame at wide open apertures where the edges and corners of the frame are darker than the center. Usually one or two apertures down from wide open and exposure across the frame evens out. The photo below shows the lens vignetting for the Canon 100-400 at 120mm (left) and the Sigma 120-400mm at 120mm (right). By f11 the exposure totally evens out for both lenses. The Sigma seems to suffer from a bit stonger lens vignette than the Canon. The other interesting difference is in the colour between the lenses. The settings on my Canon EOS-1ds Mark III were exactly the same for both sets of pictures and the sets were taken only minutes apart. The Sigma lens renders colours much warmer than the Canon lens.

Lens Vignette Test, Canon 100-400 on left, Sigma 120-400 on right

I found that the Canon 70-200 F4L and the 300 F4L have slightly less lens vignette than the  the two big zooms and that the exposure across the frame is even at f8.0. Whether lens vignette is a problem for you depends on what you shoot and your style. Correcting vignette is easy in Adobe Camera Raw and in Adobe Lightroom so if you like to shoot wide-open alot then you may need to correct this problem in post-production. But frankly, most people are purposely adding a vignette effect to their photos so I really think only the most anal photographer would be bothered by the vignetting seen on any of these lenses. But do note, the Sigma has the greatest lens vignette of all the lenses tested.

Sharpness comparisons

I tested all four lenses in the field using various subjects but the the three scenes that showed the differences in sharpness the best were the photos below. One image (the trees) was shot in overcast light, while the wooden fence and the chain link fence with signs were shot on a sunny evening . I  compared the sharpness of Sigma lens with the Canon lenses based on these three scenes.

The scene used to compare lens sharpness

Scene used to compare lenses on overcast day

Scene used to compare lens sharpness

Canon 70-200f4L vs Sigma 120-400mm lens

When I compared the Sigma 120-400 with the Canon 70-200f4L I was surprised by how well the Sigma lens performed. Both lenses seemed sharpest at f8. At the tested focal lengths of 120mm and 200mm there was little to distinguish the two lenses in terms of sharpness. The Canon slightly edged out the Sigma at f5.6 but  after that they were about even in sharpness until f16 when the Sigma had a tiny edge. Really I could not see much of a difference between the two lenses.  Below is a comparison of center sharpness in both lenses at f8. Do note the slightly bluer colour cast to the Canon lens

Canon 70-200f4L vs Sigma 120-400mm lens - Center Sharpness

Where I did notice some differences between the lenses was at the edges of the frame. The Canon is better controlled at lens vignette at wider apertures but when it comes to edge sharpness the Sigma came out on top at all apertures tested. The disturbing thing about the Canon 70-200 f4L was that there was some colour fringing (magenta) at the edges of the frame (see photo below). Maybe Canon needs to update this lens to a Mark II version to overcome this flaw. For me as a landscape shooter, I like the files I got from the Sigma in the 120-200mm range better than the files that came from the Canon 70-200 f4L.

Canon 70-200 F4L vs. Sigma 120-400mm lens - edge sharpness

Canon 300mm F4L vs Sigma 120-400mm lens

For me this test was a no brainer, I figured that the prime Canon 300mm lens would easily surpass the Sigma lens in terms of sharpness–a prime versus a big range zoom–c’mon! But, I was impressed by the Sigma lens. At 300mm, at almost every aperture, the Sigma zoom could easily match the sharpness of the Canon prime. At f5.6 the Canon had a slight edge but by f8 and past the two lenses performed almost identifcally in terms of sharpness. The Canon lens has a tiny bit more ‘snap’ (contrast) and a slightly cooler colour cast but otherwise the lenses performed essentially the same. The photo below compares center sharpness at f8 between the lenses.

Canon 300 f4L vs. Sigma 100-400 - center sharpness

When I compared edge sharpness between the two lenses I was surprised that the Sigma lens was just as sharp along the edges as the Canon prime. And the good news is neither lens showed the magenta fringing at the edges like I saw in the 70-200mm lens. I also compared the sharpness of the Canon 300mm lens coupled with a Canon 1.4x converter to give me 420mm. I zoomed the Sigma out to 400mm and compared the sharpness of the two lenses. The Canon lens with the 1.4x converter could not match the sharpness of the Sigma zoom at any aperture whether in the center or along the edges. Below is a photo showing center sharpness at f8 for both lenses.

Canon 300mm F4L with a 1.4x converter vs. Sigma 120-400

The Sigma 120-400 can easily compete with Canon’s 70-200 f4L and 300mm F4L lens in terms of sharpness. The other two lenses have a bit of a speed advantage with a wide aperture of f4 (useful for sports and wildlife shooting) but for landscape purposes, the Sigma is way more flexible combining a huge zoom range with excellent overall sharpness.

Canon 100-400 f4.5-5.6 vs. Sigma 120-400 f4.5-5.6

Ok, this is the shootout that I was really interested in. Are the two lenses comparable? I tested the lenses at 120, 150, 200, 300, and 400mm at all apertures. In the images below I present the results at f8 where both lenses tended to perform the best.

At the 120 and 150mm the Sigma was superior because it had much better edge sharpness and very little colour fringing. The Canon lens has noticable fringes in contrasty areas along the edge of the frame (see photo below). Also note that the Canon has a much cooler colour cast than the Sigma lens.

Canon 100-400 and Sigma 120-400 at 120mm

At 200mm sharpness evens out between the two lens with similar center sharpness and a a slight nod to the Sigma for better edge sharpness (see below)

Canon 100-400 vs Sigma 120-400 at 200mm

At 300mm the Canon is sharper in the center but the Sigma is sharper at the edges of the frame (see photo below) so I would call the test a draw.

Canon 100-400 vs. Sigma 120-400 at 300mm

At 400mm the Canon is clearly superior both in the center and at the edges (see below)

Canon 100-400 vs. Sigma 120-400 at 400mm

But in my other sharpness tests with the two lenses I found that the Sigma Lens gave equal or better results than the Canon at 400mm. I think the reasons for the differences are dependant on the ability of the camera or the user to get precise focus. I used Live View at 10x to focus all lenses but at 400mm I noticed that the Canon lens ‘snapped’ into focus more obviously using Live View than did the Sigma when both were racked out to 400mm. The photo of the fence below shows that the Sigma can give great results at 400mm if perfect focus is achieved

Test 2 of Canon 100-400 vs. Sigma 120-400 at 400mm

As a general conclusion the two lenses are pretty similar with the Sigma performing better at the wider end of the zoom range and the Canon performing better at the longest focal lengths or at least the Canon was easier to focus precisely at longer focal lengths. In the middle ranges of 200 and 300mm the lenses are pretty evenly matched. The Canon has a little less lens vignette but the Sigma has less colour fringing on the edges. The Sigma lens is a little warmer in colour cast than the Canon lens.

Autofocus and Image Stabilization

I did some autofocus testing with the both lenses on static and moving subjects and I really could not see any difference in lens performance between the Canon 100-400 or the Sigma 120-400. Both seemed zippy and locked focus pretty well. I had the same amount of keepers from both lenses when using auto-focus. But I am not an action/sports shooter so my tests were not rigourous. As well, in my casual tests of how well the Image Stabilization (Canon) and Optical Stabilization (Sigma) worked for handheld shots, both lenses gave me similar results. I was happy with the stabilization system in both lenses used and I could manage hand-held shots about two shutter speeds below what is recommended for non stabilized lenses.

Conclusion

As a landscape lens I really liked the Sigma 120-400 lens for its great range and convenience. It gave me as good as the results I currently get from my  70-200 and my 300mm Canon lenses and better results at 400mm than I get with my 300mm coupled with a 1.4x converter. So now I can take just one zoom lens and leave the two other lenses and the converter behind. If I were a wildlife shooter I might stick with the two Canon lenses for the extra speed that f4 gives me.

When it comes to the Canon 100-400mm and the Sigma 120-400mm it really is a matter of weighing benefits and costs. The Canon lens performs better (or is easier to focus precisely) at 400mm and it vignettes less at wide apertures. On the other hand it has the push-pull dust-sucking zoom and chromatic aberations at wider focal lengths and costs significantly more than the Sigma zoom (about $1750 new in Canada). The Sigma performs better than the Canon zoom at focal lengths 200mm or less with little or no fringing and better edge sharpness. At 300mm the lenses are eqaully matched but sharpness (or ability to get sharply-focused images) falls off a bit at 400mm with the Sigma. The Sigma is a bargain at $1000 Can.

Personally, I would buy the Sigma lens over the Canon 100-400 zoom simply because I can not see much in the way of benefits or performance for me as a landscape shooter with the Canon over the Sigma. And $750 in savings is the benefit I get from my choice.

©Darwin Wiggett - Sigma 120-400mm lens at 273mm

I have read mixed reviews about both the Canon 100-400mm and the Sigma 120-400mm lenses in terms of sharpness. Whether this is a quality control issue with the manufacturers or testing differences among reviewers is hard to dissect. I do know that many photographers use too flimsy a tripod and have poor technique (center post up, no mirror lock-up, no cable release) when using telephoto lenses and so maybe some of the sharpness issues are a result of user error. When using proper techique both the Canon 100-400 and the Sigma 120-400mm lenses can deliver professional results. I would not hesitate to use either lens.