Tokina 11-16/2.8 @ 16mm on D700 - a casual study

[Karim Ghantous]

<p>I just did a very quick test of the Tokina 11-16/2.8 on the D700 (FX mode). The aim was to gauge light fall-off and comparative resolution (centre to edge). My conclusion is that the lens is useful at 16mm although a little bit of cropping is needed wide-open.</p>

<p>I would rate the usefulness of my test as at least 7/10. I will attempt a test on slide film at some stage, using an F90X.</p>

<p>This was an informal test and it was not fully controlled (partly because the camera was hand-held). I did exposures to test light fall-off but I will not post them as I did not have confidence that the test area (the door in the photo below) was evenly illuminated. However, I can report that fall-off is obvious yet surprisingly disciplined at f/2.8 (you don't have to crop that much to eliminate it altogether) and that it begins to disappear at f/8.0. So from f/8.0 and up (you can go as wide as f/5.6 if you must) you can shoot 'real world' situations and not worry too much about either resolution or fall-off.</p>

<p>Here is the test area. One playing card was placed between the centre of the frame and the top of the frame; a second was placed at the same height, but close to the edge of the frame. I did four exposures, JPEG-fine, from f/2.8 to f/8.0 in full stop steps. I then cropped the relevant area out of each frame (no resampling) as indicated by the highlighted section:</p><div></div>

[Karim Ghantous]

<p>f/2.8:</p><div></div>

[Karim Ghantous]

<p>f/4.0:</p><div></div>

[Karim Ghantous]

<p>f/5.6:</p><div></div>

[Karim Ghantous]

<p>f/8.0:</p><div></div>

[leslie_cheung]

<p>Someone's gonna get in trouble;)</p>

[ShunCheung]

<p>Check out the image quality near the edge of the full FX frame; even @ f5.6 and f8 it is still very soft because you are using the part of the image circle that is not intended to be used. The center of the frame is far sharper with much more detail. Why would anybody pay $2500 or so for a D700 and accept such quality is beyond me.</p>

<p>As I always advice people: if you are buying an expensive FX DSLR, as all FX-format DSLRs are expensive, make sure that you have some good lenses for it. As far as I can tell, the Tokina 11-16mm/f2.8 is a fine DX lens. When you force it on an FX body, it is not so fine any more, at any focal length and any aperture.</p>

[Rene11664880918]

<p>LOL <br>

You should had listened to Leslie! LOL</p>

[Peter_in_PA]

<p>wow. Even at f8, those edges are just not there. Nice test, though.</p>

[pete_s.]

<p>Nice test! The reason the edges are not sharp may also be due to a curved field. Perhaps shoot a landscape type of image as well?</p>

<p>Also many professional print sizes are in the 5:4 aspect ratio (for instance 8x10) which means that you don't use the extreme corners at all. If you shoot for example portraits, corner performance is also of little value as the subject is not placed in the corners. And if you shoot with a shallow DOF corner performance is also unimportant as the corners would usually be out of focus.</p>

<p>Regarding shooting with different aspect ratios:<br /> A DX format lens must cover an image circle with a 14.4 mm radius. A FX format lens a 21.6 mm radius.<br /> If you crop an FX image to a square you are also using 14.4 mm radius so image quality is high with a DX format lens on FX. If you shoot for a 5:4 aspect ratio you are using a 19.2 mm radius. So corners are outside the DX image circle but the side of the frame is a just a little outside the circle or just inside depending on what side we are talking about (16mm and 12mm).</p>

<p>Shun is oversimplifying the matter by saying that the image is outside the circle that is intended to be used. Because it's a zoom you need to have a large enough image circle to cover a 14.4mm radius at the 11mm zoom setting. That is why you have a bigger image circle at 16mm zoom setting. If it was a 16mm DX prime this would likely not be the case. Of course it's optimized to the cover only 14.4 mm at all zoom settings and apertures but that doesn't mean you can't use it on FX. And who is going to stop you? The know-it-all photo police?</p>

<p>I think it's cool that it is even possible and that Nikon left the possibility open without disabling full FX frame on DX mode, which they could have done.</p>

<p> </p>

[Rene11664880918]

Back again....

I agree with Shun on this:

 

"Why would anybody pay $2500 or so for a D700 and accept such quality is beyond me."

 

Then again, If you have the lens and you also have an FX camera there are times when I think the

lens can be used.....

The following shot was taken with the 11-16 on a D300 but I wouldn't be afraid to retake the same

shot with the same lens on my D700...... If it is soft on the corners or on the ages all around, I could

live with it..... Of curse, if I was doing a project for National Geographic or any other magazine I

wouldn't...... but on a personal shot for myself, WHY NOT????<div></div>

[ShunCheung]

<blockquote>

<p>Nice test! The reason the edges are not sharp may also be due to a curved field. Perhaps shoot a landscape type of image as well?</p>

</blockquote>

<p>Pete S., I hope you understand that at 16mm, f8, you get a lot of depth of field. Your typical near/far landscape shots will require even more depth of field than a brick-wall shot. Field curvature is definitely not the problem here.</p>

<p>The issue here is that any wide-angle DX zoom such as Nikon's 12-24mm/f4 AF-S DX and Tokina's 11-16mm/f2.8 will have a very large image circle on their "long" end (but it is still a wide angle). While such image circle may appear to be large enough to project some image on the full FX sensor, the quality of the image circle is iffy outside of the DX area. The closer you get to the edges and especially the corners of the full FX frame, the worse its gets. Karim's test samples merely verify what we already know for years. (I have done similar tests with my 12-24mm/f4 DX when the D3 first came out 4 years ago.) The center portions of his sampels are all sharp with lots of details. Therefore we know that camera shake, focusing, etc. are not problems.</p>

[Peter_in_PA]

<p>So...</p>

<p>which would yield a better image? "edge to edge"</p>

<p>A d7000 with the 11-16 at 11mm?</p>

<p>Or a D700 with that lens at 16mm?</p>

<p>I bet the former!</p>

[jcoffin]

<p>Even though the corners aren't very sharp, I think it's worth noting that the lens is still transmitting quite a bit more information than you'd get on a DX sensor. I'd also note that there are a fair number of pictures for which sharpness (especially at the corners) just doesn't matter all that much. Especially when dealing with 3 dimensional subjects, there's frequently little (and often nothing) near the edge of the frame that's even close to being in focus anyway.<br>

Just for example, as I'm viewing this and (more or less) replying to Shun Cheung's comment about why anybody would accept this quality, PN has chosen to display Shun's "Let me tell you a secret" at the bottom of the page. While I'm pretty sure it was taken with a (much) longer lens than we're discussing here, it's a prime example of what I'm talking about: if the corners (and even a fair distance in from the corners) were somewhat soft, it wouldn't cause any particular problem at all.</p>

[Peter_in_PA]

<blockquote>

<p>PN has chosen to display Shun's "Let me tell you a secret" at the bottom of the page. While I'm pretty sure it was taken with a (much) longer lens than we're discussing here, it's a prime example of what I'm talking about: if the corners (and even a fair distance in from the corners) were somewhat soft, it wouldn't cause any particular problem at all.</p>

 

</blockquote>

<p>That's often the case with telephoto shots, not so much with wide angle.</p>

[jcoffin]

<p>My experience has been that with a wide angle, you have a large enough area covered that it's often impossible to get everything really sharp. Either you use a reasonable aperture and the closest parts (frequently at the bottom edge) are somewhat out of focus, or else you stop down to get those within the depth of field and end up losing sharpness everywhere due to diffraction. I've done both, and at times gotten what I'd consider reasonable/acceptable results both ways.</p>

<p>Of course, if you're willing to use multiple shots, you can do either a stitched panorama or focus stacking as well.</p>

[pete_s.]

<p>Again you oversimplify Shun. You can't always counter field curvature with lots of DOF. To test for field curvature you need to refocus the lens looking at the corners. If they become sharper the lens suffers from curvature of field at that focusing distance. But when you focus at infinity it might be a different ball game. One lens could exhibit flat field at closer focusing distances and a curved field focused at infinity, another lens design could be the opposite. This is just the way things are, not an opinion. If the lens is suffering from field curvature instead of just being bad you can take that into consideration when shooting as most subjects are not flat field anyway.</p>

<p>It doesn't make sense to suggest that you need to have some specific type of lens just because the camera body is expensive. As long as you know what you have and how you want use it, you can put whatever lens that fits on whatever camera. Photography is a creative endeavour after all :-)</p>

<p> </p>

[ShunCheung]

<p>For most people, we use teles to photograph people, sports, animals, etc. E.g. the 70-200mm/f2.8 AF-S VR version 1 is often used in parties so that the fact that it is soft in the corners at 200mm on FX is not necessarily a big deal.<br>

However, plenty of people use a 16mm wide for landscape or architecture, where corner to corner sharpness is critical. If you have to use a DX lens on FX in a pinch, that is totally fine. That is not a combo I would use on a regular basis. (E.g., the only fisheye I have is the 10.5mm DX. Occasionally I use it on the D700 in the DX crop mode. I end up with a 5MP image, which is ok for the special effect.)</p>

[ShunCheung]

<blockquote>

<p>Again you oversimplify Shun. You can't always counter field curvature with lots of DOF. To test for field curvature you need to refocus the lens looking at the corners. If they become sharper the lens suffers from curvature of field at that focusing distance.</p>

</blockquote>

<p>Pete, do you have a 11-16mm Tokina and an FX body? Please demonstrate that you can get corner sharpness with that combo at 16mm, any aperture, on the full FX frame. Or perhaps the OP can help show us. I don't have that lens but I have tested that with the Nikon 12-24mm/f4 DX.</p>

<blockquote>

<p>It doesn't make sense to suggest that you need to have some specific type of lens just because the camera body is expensive.</p>

</blockquote>

<p>That wasn't what I said. I said you need lenses designed to cover the full FX frame on FX bodies. FX bodies just happen to be expensive due to the large sensor size.<br>

I wonder, does it make sense to you that you should get FX lenses for FX bodies?</p>

[Peter_in_PA]

<blockquote>

<p>My experience has been that with a wide angle, you have a large enough area covered that it's often impossible to get everything really sharp.</p>

</blockquote>

<p>Actually... With ultra-wides, it's really easy to get everything from a few feet from the lens to infinity pretty sharp. Check out an online DOF calculator.</p>

<p>In any instance, the example at the top of this page is clearly proof that the outer edges of the 16mm image are useless on full-frame.</p>

<p>Shun is absolutely right that people who use ultra-wides seriously on any format need and demand sharp corners. One of the reasons I got the 11-16 and kept it was because of the exceptionally sharp corners on DX. I would never try it on FX myself. If I could afford FX, I'd presumably be able to afford the right lens to make FX work.</p>

[niko_korhonen]

<p>I had the 11-16 on a D300. it was brilliant, but stick to DX with it.<br>

Go and find a good used Nikon 16/17-35 for the D700, and be happy.</p>

[andre_noble5]

I solved the question of the Tokina 11-16 @16mm on a full

frame by bypassing the issue and buying their new FX 17-

35 f4. Thank you, Santa Claus. I hope you all can be so blessed by Santa.

[nigel fraustbyte]

<p>Happy Holidays</p>

 

[leslie_cheung]

<p>IQ technicality aside...</p>

<p>Karim, pick your battles. How often do you need to shoot 16mm on Film/FX? The DX 12-24mm f4 @18-24mm range on FX makes much more sense, if you just happen to have with your d700. </p>

[Karim Ghantous]

<blockquote>

<p>Why would anybody pay $2500 or so for a D700 and accept such quality is beyond me.</p>

</blockquote>

<p>I agree. It is silly. But this is why I have the lens:</p>

<p>1. I used to have DX cameras. I no longer do, but I kept the lens.</p>

<p>2. I might use a DX camera in future (I also kept my Tamron 17-50/2.8).</p>

<p>3. I knew that I could use it with FX sensors at 16mm (if I had nothing else).</p>

<p>4. I am going to use Micro 4/3 cameras in future.</p>

<p>5. I have been justified in keeping it for a further reason: the RED Scarlet-X is definitely a camera that I could exploit in future. Its sensor is equivalent to DX.</p>

 

<blockquote>

<p>I think it's cool that it is even possible and that Nikon left the possibility open without disabling full FX frame on DX mode, which they could have done.</p>

</blockquote>

<p>I agree. I think the engineers understand how lenses work in the real world.</p>

 

<blockquote>

<p>It doesn't make sense to suggest that you need to have some specific type of lens just because the camera body is expensive.</p>

</blockquote>

<p>I will agree with this, however: why have a good camera and spoil it with an unsuitable lens? Or shoot JPEG instead of RAW? Some photographers are deluded enough to think that a 6Mpx DSLR out-resolves 35mm film (even I was sucked in all those years ago). That doesn't preclude the use of 6Mpx DSLRs, but it does preclude spouting nonsense about these things. My test was exploratory and in no way recommends this lens over a better one, all things being equal. I am encouraged, though, that this lens performs better than expected.</p>

 

<blockquote>

<p>I solved the question of the Tokina 11-16 @16mm on a full frame by bypassing the issue and buying their new FX 17- 35 f4.</p>

</blockquote>

<p>I look forward to seeing more tests, but I am encouraged by the one you posted a few days ago (are you doing more tests yourself?). I am finding that third party lenses are often better value than Nikkors.</p>

 

<blockquote>

<p>Karim, pick your battles. How often do you need to shoot 16mm on Film/FX?</p>

</blockquote>

<p>Probably never, but I'd like to see the results. Curiosity requires no justification. :-)</p>