Sigma 10-20mm f/3.5 EX DC HSM
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Lab Test Results
September 14, 2009
by Andrew Alexander
At PMA 2009, among several new lenses Sigma announced the 10-20mm ƒ/3.5, a constant-aperture version of its ultrawide-angle zoom. The lens is slightly larger and heavier, taking 82mm filters instead of 77mm.
The lens is compatible only with APS-C sized sensors: using the lens on a full-frame style camera will produce vignetting at any focal length (though it is more prominent below 14mm). On an cropped-frame camera, the lens will produce an effective field of view of 16-32mm (Canon) or 15-30mm (Nikon and others).
The lens ships with a petal-shaped lens hood, and is available now for approximately $650 in Sigma, Canon, Nikon, Sony and Pentax body mount configurations.
Sigma has made some definite improvements with this lens, specifically to its performance at 10mm. However, this comes with a slight degradation in quality at 17-20mm.
With the lens used at its widest angle and wide open at ƒ/3.5, the lens produces impressively sharp images throughout the majority of the frame (~1.5 blur units) with soft corners occurring only at the extreme edges of the frame. Zooming out these soft edges disappear, and performance is essentially the same between 12-20mm: around 1.5 blur units in the center, and 2 blur units in the corners.
Stopping down produces marginal gains: by ƒ/8 it's about as sharp as it will get, but the sharpness profile is only slightly improved from what we see at ƒ/3.5, and it's already pretty good there. Diffraction limiting sets in at ƒ/11, where performance is still quite good at around 1.5 blur units across the frame between 12-20mm. Sharpness begins to fall off at ƒ/16, and becomes mediocre at ƒ/22 (3-5 blur units).
Chromatic aberration is a bit higher than in the previous version of the Sigma 10-20mm. While the ƒ/4-5.6 version, wide open at 10mm wasn't bad in the corners, the ƒ/3.5 version is fairly high in the corners (~10/100ths of a percent of frame height) at every aperture setting. Average CA performance is also slightly higher.
Corner shading has improved somewhat from the predecessor model of the 10-20mm. Corners are always slightly darker than the center of the frame when using this lens: it's just a question of how much. Used wide open, the lens is subject to the greatest amount of light falloff: at 10mm and ƒ/3.5, we note corners which are 2/3EV darker than the center. It's better at any other setting: at ƒ/5.6, corner shading is around 1/3EV, and at ƒ/8 and smaller light falloff hovers around a quarter-stop differential.
Ultrawide lenses are typically prone to distortion, but in this case the Sigma 10-20mm ƒ/3.5 keeps distortion to a minimum. It's at its most prominent at 10mm, where barrel distortion shows at +0.8% in the corners and 0.5% on average. This reduces as the lens is zoomed in, and reaches almost 0% distortion at 15mm. After 15mm the lens enters pincushion territory in the corners, showing -0.25% in the corners at 20mm.
The Sigma 10-20mm ƒ/3.5 uses the HSM focusing motor, resulting in fast, near-silent autofocus operation. The lens took about 1.5 seconds to go through its focusing range. Point to point focusing seems to go a bit quicker. Autofocus results can be overridden at any time by just turning the focus ring. The front element doesn't rotate during focus.
Macro performance is, not surprisingly, poor. Magnification is 0.15x, though minimum close-focus distance is 24cm (around 8 inches).
Build Quality and Handling
The Sigma 10-20mm ƒ/3.5 uses a dense plastic construction with a fair amount of heft to it. The lens balanced well on our Canon 20D testing body. The lens sports an all-black matte smooth finish with parts of it using the Sigma rubberized coating. The body mount is metal, while the 82mm filter threads are plastic.
The lens has only one switch on it, which enables or disables autofocus. It has a distance scale located under a clear window, but no depth of field markings or infrared index. Distance is measured in feet and meters.
The zoom ring is the larger of the two, positioned closer to the body mount. The ring is about 3/4'' wide, composed of rubber with deep ribbing. Resistance on the ring is just right - not too firm, not too smooth. Zoom creep is not a factor. It takes about 25 degrees of turning to run through the range of focal lengths, and zooming in results in a quarter-inch of lens extension.
The focus ring is mounted near the front element of the lens, a thin (1/4'' wide) ring composed of the same rubber, with deep ribs. The focus ring turns all the way around the lens: there are no hard stops, but soft stops at infinity and closest focus. The lens will focus past infinity. The focus ring on this copy of the lens was very stiff, and took some firm two-finger effort to move it.
The lens ships with a short, petal-shaped lens hood. The hood uses a bayonet mount to attach to the lens, and reverses on the front for storage. The lens hood adds 1 1/2'' to the overall length of the lens when mounted.
Sigma 10-20mm ƒ/4-5.6 EX DC HSM ~$460
The original Sigma ultrawide-angle zoom still holds its own, being slightly sharper at the telephoto end of its spectrum than the newer version. CA is also slightly better in the older version, though the newer version improves on corner shading and distortion. The new version uses 82mm filters instead of 77mm, but offers the constant ƒ/3.5 aperture.
Canon EF-S 10-22mm ƒ/3.5-4.5 USM ~$750
Canon's 10-22mm may be a comparatively old design (2004) but it still holds its own compared to the Sigma. While it doesn't offer a constant aperture, it's just as sharp and has a touch more telephoto distance to offer. CA tolerance is a bit better, distortion is about the same but there is a bit more corner shading.
Nikon 10-24mm ƒ/3.5-4.5G ED AF-S DX Nikkor ~$850
Nikon's 10-24mm isn't a constant-aperture lens, but it offers slightly more room on the telephoto end. The lenses are about equal in sharpness, though the Nikon definitely has a bit of an edge in CA tolerance. In the Sigma's favor, corner shading and distortion are better-controlled. The Nikon uses 77mm filters.
Tamron 10-24mm ƒ/3.5-4.5 Di II LD SP AF ~$500
Tamron also has a 10-24mm lens on offer, also a variable aperture lens. In this case, the Sigma is definitely the winner, being sharper, showing less chromatic aberration, and showing less distortion and light falloff. The Tamron lens uses 77mm filters.
Tokina 10-17mm ƒ/3.5-4.5 AT-X 107 AF DX Fisheye ~$579
While we haven't tested it, the Tokina 10-17mm lens is a fisheye, in case you're not interested in rectilinear lenses.
Sigma has made some dramatic improvements in this constant-aperture version of the 10-20mm lens, and has made them where they count: at the 10mm end of the focal length spectrum, where (arguably) the majority will probably use this lens. The lens is very sharp, though we're seeing slightly more CA than we did in the previous version. Distortion is much improved, as is corner shading.
Upgrading from the previous version of the lens really isn't necessary unless you have a dramatic need the extra light gathering ability: if you have any 77mm filters you use with the old version, you'll need to upgrade to larger 82mm filters. For shooters looking to explore the ultra-wide experience, they should find the 10-20mm ƒ/3.5 lens doesn't disappoint.
Unfortunately, our 20D blew its shutter while were doing our sample images, so until we get that fixed you'll have to live in suspense. We'll post a note when we have the sample images available.
Sigma 10-20mm f/3.5 EX DC HSM User Reviews
9 out of 10 points and recommended by Buceemie (1 reviews)Silent, fast auto focus, image quality at wide end, build, handling, low distortion for a fish eye, constant aperture essential for videoWeight
SLR Gear gave an accurate review regarding image quality. A little soft around the edges at the 20mm end, otherwise excellent. Most of the time you're at the wide end of this lens anyway and that's where it excels. Nice to have the versatility at the narrow end, it's there when you need it, and worth the extra weight.reviewed September 24th, 2013 (purchased for $649)
This focal range is so much fun to work with and play with! Beautiful dramatic shots, and I never tire of the perspective, unlike a circular fish eye which is kind of a gimmick after so long. This is a lens you can shoot all day, and not be like Okay enough of the fish eye already!
Focusing is fast, so quiet I can barely hear it, and the feel of it in the hands is really great. Heavy but worth it's weight. I have an excellent 15mm prime lens that is super sharp, small and light, but still bring the sigma on all my trips.
The 3.5 version of this lens is worth full retail price of $650 I have no regrets. It produces the shots people love, more often than any other lens I have and that's saying a lot.
If you think you might someday shoot video with your SLR then the constant aperture of this lens is worth the price difference over the cheaper version. Or if you shoot often in low light settings like around here winters are dark, or night shots, or sports, really nice to have the extra f-stop.
So happy with this lens. I hope it lasts forever and it looks like it will.
9 out of 10 points and recommended by kiwijono (6 reviews)Very sharp center, nice feel, good auto focus, very useful rangeCorners at 10mm could be sharper
Although I can't compare this to other UWA lenses I can compare it to other zoom lenses I have (such as Sigma 17-70) and this lens beats them hands down. Feel and build quality is excellent. HSM focussing is wonderful. Flare resistance is surprisingly good for a UWA. I love this lens and the perspective it allows. At f3.5 it has very good sharpness (at least in center) and I find f3.5 particularly useful for indoor shots or where you want a bit of bokeh on close ups (can only get so much on a UWA). Colours look nice tooreviewed September 20th, 2013 (purchased for $515)
Example image at 16mm (f8): http://www.flickr.com/photos/kiwi_jo...in/photostream.
Example image at 10mm (f5.6): http://www.flickr.com/photos/kiwi_jo...in/photostream
10mm f11 sharpness: http://www.flickr.com/photos/kiwi_jo...n/photostream/
Bokeh example at 20mm (f3.5): http://www.flickr.com/photos/kiwi_jo...in/photostream
Creative examples at 10mm http://www.flickr.com/photos/kiwi_jo...in/photostream and http://www.flickr.com/photos/kiwi_jono/8244294796/
Contrast f9.5 at 20mm: http://www.flickr.com/photos/kiwi_jo...in/photostream
My only criticism is that at 10-12mm the corners can be soft below f5.6 and a still a little soft below f8. Still perfectly useful in my view. At 12 - 15mm corners are perhaps a little soft at times wide open. And from 15-20mm the quality is very good across the frame from f3.5 (and better IQ than my 17-70 at 17 - 20mm).
Overall I love this lens!
10 out of 10 points and recommended by r_jak (1 reviews)Range, low distortion, good color saturation and contrast. Well constructed. Fast and accurate focus. Acepts filters.No weather sealing.
The build quality is very good. Image quality (sharpnes, colors, contrast) is very good at all settings.reviewed April 2nd, 2013 (purchased for $850)
AF is fast, quiet and very accurate.
Sharpness in the center and borders is very good, at the extreme edges is a bit soft under 12mm wide open.
Near 20mm the edges are good again, and the lens can be used wide open without problems.
I catch very nice pictures. Use it is very very fun.
7 out of 10 points and recommended by mearussi (1 reviews)constant f3.5, accepts filtersthough the center is sharp at all focal lengths and apertures it is almost useless at 10-12mm due to poor edge sharpness and very high lateral color starting about 30% out from the center
I bought this lens specifically over the Sigma 8-16 because I needed it to accept 80A filters and have a constant f3.5 aperture because I do a lot of both low light handheld and tripod night shooting. But if these two advantages are not important to you then the 8-16, being much sharper, is a better choice.reviewed May 11th, 2011 (purchased for $500)
9 out of 10 points and recommended by ReverendOlaf (3 reviews)Super wide! Great performance at 10mm 5.6+Not much of an upgrade from the original version
This is the only Sigma lens I purchased online (fearful of legendary Sigma QC), and I can't see the issues that others complain of. It could be due to luck, or perhaps I'm less demanding than others. Anyway, here's my $.02reviewed December 19th, 2010 (purchased for $650)
I sold my 10-20mm f/4-5.6 to purchase this lens in some quest to get the ultimate 10mm lens, and while I may have found it, I'd just assume have the other lens and $200. That being said, this is an outstanding lens. From f/5.6 on up it's outstanding, and I rarely need to use it faster than that. Typically I shoot at f/8 with this lens, where it's even sharper wit gains mostly at the edges. When I want or need to shoot wide open, it's rather sharp in the middle. Rarely is this an issue, but if it's something that will bother you, perhaps you should try before you buy. Distortion isn't that bad, nor are CAs an issue.
Handling wise, the HSM is comparable to the best AFS lenses, and the zoom ring is well spaced. The build is solid, but I'd rather the body gain 10mm and have the zooming happen internally. As others have mentioned, the hood is a wreck. It desperately wants to fall off, and since the wide field of view makes having the sun more likely to be an issue, that's a problem.
So, if you're new to wide angles, I'd suggest the Sigma, but if you're on a budget, go for the older 10-20mm f/4-5.6. It's just as good at f/8, and 77mm filters are way cheaper (I love using a grad nd with this lens).
9 out of 10 points and recommended by x_holger (1 reviews)very resistant against ghosting and flare, very sharp in the centersoft edges at 10 and 12mm unless stopped down to F5.6-8
Contrast is very good at all settings.reviewed December 10th, 2009 (purchased for $740)
The lens is very resistant to flare and ghosting, much better than the competitors. I compared it to various Nikon and Tokina super wide zooms.
AF (HSM) is accurate, fast and quiet and the build quality is very good. The MF ring is well dampened and feels comparatively precise and accurate.
Sharpness in the center is very good, the borders are also fine but the edges tend to be soft at 10mm and 12mm unless the lens is stopped down to F5.6-8.
At 17mm and 20mm the edges catch up nicely and the lens can be used wide open without problems.
All in all the Nikkor DX 12-24 or the Tokina DX 11-16 are sharper near the edges but the Sigma wins in terms of contrast, resistance against flare and ghosting and AF performance.
In comparison the AF performance of the Tokina was really a problem, especially at 16mm and the Nikon didn't autofocus very well at 12mm.
Both the Nikon and the Tokina are much more difficult to focus manually due to focus shifts when changing the focal length.
Watch out for sample variatons! My first sample of the Sigma 10-20 was decentered and had to be exchanged. The second sample is fine.
4 out of 10 points and not recommended by RnR (2 reviews)Good quality build, great colours / contrast, low distortion even at 10mmHorribly soft rendering it unusable
I waited for this lens and finally entered the world of 10mm wide angle. I instantly fell in love and started using this lens as a walk-around lens. It's range of 10-20mm is much more useful than the Tokina 11-16 and the 3.5 is only marginally slower than the Tokina at 2.8, so I was pretty excited.reviewed October 11th, 2009 (purchased for $740)
I got one of the first ones I saw in Canada. Most of my landscape photos turned out great, but there was a nagging concern as many of my 'closer focus' photos were all out of focus or horribly soft. I blamed it on user error, until I got a Nikon 10-24 to try side-by-side and did some basic brick wall and ruler tests. At 33%, I loved the look of the Sigma images: much warmer than the Nikon, and slightly less distortion at 10mm. But then when I zoomed in at 100%, it became abundantly clear that, even on the brick wall, whether it be 10mm, 12mm, 15mm or 20mm, and whether F3.5, 4.5, 5.6, 8, 11, 13, or 16 the center sharpness was clearly inferior to the Nikon. In fact, it was unusable wide-open as the center was so soft.
Let's face it, colour and distortion can be fixed in post-processing, but nothing can correct poor focus or lack of sharpness. (I'm using a D80 by the way)
Despite the Nikon costing quite a bit more, I will definitely be returning the Sigma for the Nikon. I'm very disappointed as I had heard concerns over Sigma's quality control and clearly I got a very bad example, but I'm not willing to take another chance with them on a lens that costs +$800 CDN.
One other minor complaint is that the hood doesn't "lock" into place like the Nikon does, meaning that I had a few photos with strong vignetting from the lens hood not being perfectly in place. Just a warning to others.
9 out of 10 points and recommended by ChrisI (3 reviews)Build quality, focus speed, zoom range and smoothnessEdge sharpness wide open, CA
I compared performance and test images taken with the Sigma 10-20 f/3.5 against my Nikon 16-85 VRII, which I consider my sharpest lens. The photos were taken with a Nikon D5000, tripod mounted, no digital sharpening, of fixed targets on my living room wall at about six feet. The targets consisted of newspaper at the corners and a large US map in the center, with a variety of detail and some color. Illumination was provided by house lamps and a photo flood light. The images were compared side by side at 200% enlargement on my monitor.reviewed October 2nd, 2009 (purchased for $650)
The Sigma 10-20 was not as sharp as the Nikon 16-85 in the very center of the image at comparable focal lengths (16mm and 20mm) and apertures, although was very close by f/5 and nearly the same at f/8. At the edges of the image however, the Sigma 10-20 was as sharp or sharper and had better contrast at f-stops tested, 3.5-8. I have no lenses to compare the Sigma 10-20 to at shorter focal lengths.
Focus speed with the Sigma 10-20 is very fast and quiet, similar to the Nikon 16-85. There is some variation in auto focus reproducibility but seems to be within a reasonable margin and will likely not be noticeable in most photographs. The zoom action of the Sigma lens is smoother than my Nikon lens. Zoom action is important if one likes to zoom in or out while recording video clips. The lens is somewhat larger and heavier than the Nikon, but roughly the same size.
Chromatic aberration/color fringing has been reported as being an issue with many wide angle lenses, including this lens. I will comment on this after shooting some high contrast scenes outdoors if I feel it is significant.
This is my second copy of the lens. The first copy appeared to have a slight back focus problem at 10mm at short focal distances as indicated by variations in auto focus performance vs manual focus to achieve optimal sharpness. Optically, the first copy appeared as sharp as this one and likely would have been acceptable to most users.
Edit 9-30-09: The lens performed well in the field yielding good color and contrast. Flaring is visible as the lens is tilted towards the sun. I used my baseball cap to shade the lens and would also recommend the lens hood in most situations. At 10mm, sharpness is acceptable at f3.5 in the center and quite soft at the edges. Sharpness at the edges seems fairly good by f4.5. Color fringing is quite evident in high contrast areas near the edges of the image however it was not so bright as to appear in my uncorrected 8x10 prints. Also it was quite easy to reduce the fringing to a non-issue with CA correction using Adobe CS4. Auto focus was accurate.
Overall I'm quite pleased with this lens and I'd say it outperforms my expectations for sharpness and vignetting but would have been nice to see the CA better controlled . I will keep this lens, however the older version (f4-5.6) is reported to be as good or perhaps better in some respects so I'd recommend the f3.5 lens only if the constant aperture is of interest to you.
7 out of 10 points and not recommended by dadgummit (6 reviews)Nice build, Decent apertureSoft at large Apertures,
I purchased this lens because the Tokina 11-16 was out of stock everywhere and I thought if this lens can have good IQ, a slightly slower aperture but a larger zoom range it would be a winner.reviewed September 24th, 2009 (purchased for $650)
This lens will produce very soft images wide open. It is much better at f5.6 and pretty good at f8. On the other hand the HSM motor is great, focuses very fast and seems accurate.
If I wanted a Ultra Wide Angle that only produces good results at f8 I would not have paid the almost $200 premium over the old Sigma.
The construction of the lens is really nice, it has a good heft and feel to it. The zoom is nicely dampened and the HSM motor is great. The only small complaint is the Huge plastic ring on the front end that extends out past the body of the lens. When you put the camera down it rests on that plastic piece, I am afraid that it will break.
Long story short, It is not a bad lens but it is no better than the much less expensive 10-20mm that Sigma also sells. IMHO either get the original 10-20 Sigma, Find a Tokina 11-16 or pay the price for the Canon 10-22.
2 out of 10 points and not recommended by nthbeach (3 reviews)Build quality is goodVERY SOFT!! This lens is a total lemon!
This would have to be the WORST lens i have ever used!reviewed September 20th, 2009 (purchased for $800)
Sigma has done it again by making a lens that promises a lot, but only delivers disappointment!
Its a pity, because i really wanted to like this Lens.
I tested this lens against a much older Sigma 10-20 f4/5.6
And at all focal lens the new Sigma failed dismally!
It performs badly up until f8, and then it is barely usable.
It even performed badly against my compact camera.
It makes me wonder why would Sigma create a constant f3.5 aperture lens if it is unusable at anything under f8?
Perhaps i just purchased a bad copy.
But this is typical of Sigmas quality control.
Its like buying a lottery ticket as to whether or not you get a "decent" lens, let alone one that is usable!
Save yourself the time, Money and disappointment!
Stick with a reliably brand and stay well away from all SIGMA!
This has happened to me on several occasions, and through my own stupidity, it has taken me while to learn the lesson, NEVER buy a SIGMA lens!!
9 out of 10 points and recommended by kinematic (13 reviews)Less distortion over the older model, very sharp at 10mm, great build quality.82mm Filter is a rather large size and almost pointless with a polarizer. Also totally pointless lens hood.
After using the F3.5 for a shoot all weekend (Local Theatre company) I must say that I am very impressed by the F3.5.reviewed September 15th, 2009 (purchased for $650)
First things first, compared to the F4, it has slightly less distortion at the widest end. Now I should qualify this a bit. The F4 had a unique distortion at the very edges. I would say that the distortion on the F3.5 is more gradual with to me is more desired rather than the abrupt distortion on the F4. This probably has something to do with the larger front element. I can't confirm this, but I might have to see if I can get a copy of DxO's testing software to determine what kind of distortion I'm seeing in my photos compared to my F4 versions. If I was to guess, I would say about half or less the amount of distortion.
The reason I got this lens was for shooting architectural or landscapes with minimal distortion. The sharpness seems to be on par with the older model I had, maybe a touch sharper. I can't afford the Canon 14mm with a full frame camera which is what I'd prefer to do, but this seems to work very well to give me 16mm field of view with very little distortion.
Vignetting also seems to be reduced in this copy. I see far less of it even at F/5.6. I'm also using a slim kenko Pro-1 Polarizer and it does not create any shading.
Point lights look fantastic with this version because of the extra aperture blade with 14 points on the stars making very beautiful looking 'Sunstars'. Is it worth it for this alone... that's a matter of subjective opinion, but I like the 14 points over the 12 points personally.
It isn't all roses though. You have be very careful about strong lightsources that may cause flare. This lens is easily prone to lens flare especially at night (and it isn't pretty when it does). I had a light source just left of my frame and the flare came in looking like water spots. Fortunately I could see them in my LCD viewfinder and I recomposed my image. Lenshood doesn't help much to combat this. The lenshood is pretty much pointless, and do be careful with it, for some reason the version I had was very loose and it was very easy to lose the hood in the reverse position. In the active position it wasn't so bad, but either way, it is a pointless accessory.
I don't recall if this is how it is on the F4 version, but with the lenshood in reversed position, it sticks out beyond the rim of the lens. This can be a good thing for those that don't believe in using protective filters as it gives just a little more protection if you hit the front of the lens at the edges, however it's a problem if you use slim polarizers on the front element as it's very difficult to turn your polariser as it is almost inset into the rim of the lenshood. Easily resolved by removing the lenshood.
The lens is slightly bigger so it does need a little more adjustment in your lens bags if you already had it tight. The AF/M switch is different on this model. It's almost like they redesigned it and made it an interchangeable unit. I'm not willing to take it apart to find out why it's designed this way, perhaps something to do with the way how they have to make it adaptable for the different camera mounts. I suspect they are using a more easily interchangeable part with circuitry built right into the switch for each camera model/mount. If you have ever taken apart a sigma lens, they all have very interchangeable parts, a smart thing to do from a manufacturing point of view.
Is it worth the extra $100 I paid for it. For me so far yes. Distortion was my number one reason why I wanted this lens and for me it seems to deliver less of it. I have since gone full format and returned this lens, but I would still highly recommend it if you're looking for a very sharp at 10mm UWA lens for stuff like architecture work, this is the lens to get.
8 out of 10 points and recommended by mgolbe (2 reviews)Solid build, great range, handles flair/ghosting well.Not very sharp. Bokeh is only so-so.
I like the way Sigma builds its EX (for extra expensive) lenses and this model is as good as the other two EX lenses I own. It can take 82mm filters and one can use the lens cap even when the butterfly hood is in place.reviewed July 16th, 2009 (purchased for $650)
I need top-quality glass for my work but I'm willing to compromise for $$$ savings when I can. I have a Tamron 17-50mm 1:2.8 which is incredibly sharp - a great buy. (It is tested here at SLRGear.) I compared it to this lens, both set to 17mm under very controlled conditions. (First I tested the new Sigma for focusing accuracy. It was short by just a small bit. I made the adjustment in my Nikon D300.)
In overall impression the Sigma is comparable to the Tamron, a bit warmer but with similar contrast. Distortion at 17mm is much less than the Tamron's, but of course gets quite extreme as you near 10mm. In resolution there were large differences. At 17mm, both center and corners, the Tamron outperformed the Sigma for sharpness by a very noticeable margin with fast apertures. The gap starts closing around f/11 and the two lenses are roughly equal by f/22.
The Sigma's bokeh is a bit rough. Specular highlights aren't quite round, have some striations and halo, and are not smoothly monochromatic. None of these shortcomings is a killer, I'm just a perfectionist.
If you'll never print larger than 8x10" this lens might be ideal for you, but it is not truly up to professional caliber. However, neither are any of the other ultrawide zooms, it seems. The exceptions cost two or three times as much and don't go nearly as wide.