DxOMark Lens Scores and APS-C vs. Full Frame

[ShunCheung]

<p>Center looks good.</p><div></div>

[ShunCheung]

<p>This is not even corner, just off center. And this is 12mm at f8, not wide open.</p>

<p>Are you happy with such results?</p><div></div>

[JDMvW]

<p>Um,<br>

for architectural shots we use something like the PC-E. I don't recall anybody recommending the ultrawide zooms for architectural use.</p>

<p>I have shot some architecture on APS-C with a zoom in the 17mm range, and with ditto on 35mm-sensor with 24mm in cases of 'emergency'. It's amazing, to me anyhow, how well those perspective distortions can be corrected in post processing, when you have to. Also, as with any wide angle, it really helps if you keep the axis of the lens parallel to the ground to avoid keystoning as much as possible.</p>

<p> </p>

[ShunCheung]

<blockquote>

<p> how well those perspective distortions can be corrected in post processing, when you have to. Also, as with any wide angle, it really helps if you keep the axis of the lens parallel to the ground to avoid keystoning as much as possible.</p>

</blockquote>

<p>JDM, I see you are still not getting the problem.</p>

<p>I am not talking about the keystoning, etc. Since I was using it at 12mm, I had to tilt the camera down a little so that the building would occupy the top part of the image and we have some details near the edge of the frame. Otherwise, it would be all blue sky and it is difficult to notice any lack of sharpness in the sky. :-)</p>

<p>Here I am attaching a crop of the top-left one quarter of the original image. It should be pretty obvious that the center of the frame, even the top part of the build above the center, is quite sharp. However, when you move to the left side of the frame, it gradually becomes unsharp to a degree that it is no longer acceptable even before we reach the edge. That is a problem in the lens, or more precisely, when using this lens on a high-pixel DX body such as the D7100. It doesn't matter what the subject matter is; instead of a building, you could have some mountain in a landscape image and it'll have the same lack of sharpness issue.</p>

<p>I have had this lens since 2004. When my main camera was the 12MP D2X and D300, the problem wasn't as obvious. When you pixel peep at a 24MP image, it is like making a huge magnification.</p>

<p>I don't have the Tokina 11-16mm/f2.8. It would be interesting to do something similar on a D7100 (or D5200, D3200 also with 24MP sensors).</p>

<p>Since the attachment is 3000x2000, it will appear as a link. Please keep in mind that it is a rather large 1M file if you choose to download and view it.</p><div></div>

[JDMvW]

<p>I don't think you are "getting the problem" either about the general utility and uses of ultawide lenses-- although I will stipulate that you may have some decentering in this case. It doesn't look so bad on the right to me. I'm surprised more about how sharp the center is in your picture. ;)</p>

<p>By the way, the cameras I am shooting my ultrawides on are respectively 22MP and 18MP, so it's not exactly lo-res.</p>

<p>I think that we're beating it to death here. You don't like ultrawides since you are clearly not much inclined to accept "contradictions" inevitable in such lenses. Fine.</p>

<p> </p>

[eric_arnold]

<blockquote>

<p>Are you happy with such results?</p>

</blockquote>

<p>Shun, i see your point, but it's kind of moot to me because that's not typically how i shoot ultrawides and thus not representative of the type of composition and framing i'd use that lens for. when using an UWA, i always look for a strong foreground image and something which connects to the background. in this case, there's nothing central to grab the eye; the pool isnt very compelling, and the whole image is kind of flat. when i use an UWA, i want an image that is going to pop out with a wider-than-normal perspective which emphasizes the strength of that lens. but in this case, this isn't a shot which needed to be shot with an UWA, nor takes any particular advantage from its use. so while you may be making a technical point about the 12-24, that point is undermined by the lack of aesthetic quality in the shot--which to me at least can trump perfect corner sharpness. and, as JDM has suggested, to achieve technical perfection with that type of shot, you'd use a T/S lens ideally anyway.</p><div></div>

[ShunCheung]

<blockquote>

<p>Shun, i see your point, but it's kind of moot to me because that's not typically how i shoot ultrawides and thus not representative of the type of composition and framing i'd use that lens for.</p>

</blockquote>

<p>Eric, perhaps that is moot to you, but it is certainly not moot to me. I shoot a fair amount of landscape so that having corner-to-corner sharpness is critical to me. Same for those who shoot architecture.</p>

<p>I received the D7100 around 11:30am on Saturday morning. I just used an easyily available subject to demonstrate that point and posted those image samples about 5 hours later. Hopefully that confirms DxO Mark's findings and answes the question John Wall had in his opening post.</p>

<p>And no offense, but images showing someone's bottom side right in your face in not exactly my cup of tea either. But you sure have the right to pick your subject matters.</p>

<p>P.S. Once again, I have never used the Tokina 11-16mm/f2.8. People are more than welcome to post some samples of such lenses on the wide end on modern high-pixel APS-C format DSLRs. Maybe the Tokina is better than the Nikon 12-24 DX. I also have Nikon's 17-55mm/f2.8 DX, and it has similar weaknesses near 17mm; so do the newer 10-24mm DX AF-S and 10.5mm DX fisheye.</p>

[jwallphoto]

<p>The smear you experienced is interesting, and I wonder if it has something to do with 12mm being focused at infinity. When I shoot at 12mm I'm usually very close to my foreground and often stopped down to f/22. I haven't noticed that smearing. Maybe it's happening out in the distance where it's not so noticeable.</p>

<p>THE FULL FRAME:<br>

<img src="http://2.bp.blogspot.com/-K7kSXPepKjY/UVDzJ1MdumI/AAAAAAAAHeA/Xakro2r9T0Y/s1600/PhotoNet1A.jpg" alt="" width="465" height="700" /></p>

<p>THE CROPPED LOWER LEFT CORNER:<br>

<img src="http://4.bp.blogspot.com/-Ja20wHYU8Lk/UVDzJMEIPQI/AAAAAAAAHd8/nyIrOfDIaC8/s1600/PhotoNet1B.jpg" alt="" width="467" height="700" /></p>

[ShunCheung]

<p>John, first of all, you are not showing a 100%, pixel-level crop, and your camera is a D300, 12MP.</p>

<p>Your crop is taking up about 15% of the original frame, as shown by the outline below.</p><div></div>

[ShunCheung]

<p>If I make the equivalent crop, it would be like this.</p><div></div>

[ShunCheung]

<p>Now, if I take that crop and then scale down the long end to 700 pixels as John did, I get this. All of a sudden it looks pretty good.</p>

<p>This image would be similar to the pixel-level crop from a 4MP DSLR, such as the D2H. The 12-24mm/f4 AF-S DX was introduced in 2003, the same year the D2H was introduced. On a 4MP DSLR and perhaps a 6MP, that lens looks perfect even on the wide end. On the 24MP D7100, not so much. That is why these high-pixel DSLRs are so demanding on lenses. However, if you don't need 24MP, 36MP, you can always down sample.</p>

<p>IMO, 16MP is a lot on the DX format. To some degree, I kind of wish that Nikon had stopped there instead of going to 24MP, even on the D3200.</p><div></div>

[eric_arnold]

<blockquote>

<p>no offense, but images showing someone's bottom side right in your face in not exactly my cup of tea either. But you sure have the right to pick your subject matters.</p>

</blockquote>

<p>kind of a reach there, shun. the shot illustrates a mural artist straddling a ladder and a building, demonstrating the lengths he is willing to go to paint in a public space. i chose that shot to show how i shoot ultrawides,i.e. strong foreground image which shows DoF within the composition, i.e. linear movement from foreground to background or bottom to top in this case. not exactly what i would call a butt shot, by any means. but if that's what resonates about that particular image to you, who am i to opine otherwise? i guess beauty remains eternally in the eye of the beholder ;)</p>

<blockquote>

<p>On a 4MP DSLR and perhaps a 6MP, that lens looks perfect even on the wide end. On the 24MP D7100, not so much. That is why these high-pixel DSLRs are so demanding on lenses. However, if you don't need 24MP, 36MP, you can always down sample.<br>

IMO, 16MP is a lot on the DX format. To some degree, I kind of wish that Nikon had stopped there instead of going to 24MP, even on the D3200.</p>

</blockquote>

<p>well, even if nikon didnt stop no one is holding a gun to our heads and demanding that we buy cameras which outresolve our lenses. at some point, that is on the consumer, to be able to discern what's marketing hype and what's genuine innovation. i've said this before, but the d300 was an awesome body which only needed to be improved on in a few areas, such as hi-ISO performance (and maybe video). instead, nikon gave us the d7000 and now the d7100.</p>

[ShunCheung]

<p>If I have to use a D300 today, I won't have any really major complaints, but technology has evolved since 2007. As any high-tech electronics, current products have their advantages, although sometimes those advantages are minor. Moreover, if you sell your images, 12MP is on the low side nowadays.</p>

<p>For whatever reason, Nikon feels that you must have 24MP on DX DSLRs today, as all of their current ones are 24MP: D3200, D5200, and D7100. (Nikon may still list the D300S and even D3000, etc. as "current" models on their web site, but I have to disagree that they are current.)</p>

<p>Meanwhile, Canon has just announced two 18MP, APS-C format DSLRs this month. So apparently 24MP is not absolutely necessary in 2013.</p>

[eric_arnold]

<p>i'm still using my D300s and D3s, both of which are 12mp. i dont really buy the 'evolution of technology' argument 100% because a) the d7000/d7100 are worse in some ways than the d300s, and certainly dont raise the bar to the same degree that camera did in 2007 and b) the d600/800 are worse in some ways than the d3s and d700. i would agree that a 6mp or 10mp sensor doesn't really cut it in 2013, but 12mp seems like a sweet spot as far as giving good performance without the pixel density and diffraction issues of larger sensor cameras -- which impacts lens performance in some cases. now, had nikon made a 16mp d400 with the same ergonomics, body, and button layout as a d300, or, say, a d700s with the d3s sensor, that argument might hold more weight to me. but there are plenty of cases where supposed leaps in technology haven't been all that beneficial to the consumer. if the 12-24, which was considered a near-pro lens when it was released, no longer cuts the mustard on a 24mp DX sensor, and nikon doesn't have an answer for that, i.e. a w/a DX lens which isnt outresolved by the sensor, then that's indeed an issue, to say nothing of all the other consumer-grade lenses which show their limitations on that sensor.</p>

<p>the other issue is that where technology actually has evolved since 2007 is in mirrorless ILCs, of which nikon still doesn't have an entry. i'm not sure a great argument can even be made for investing in DX at this point, since the hi-end m4/3 bodies, sony Nex, and fuji's X-series offer equivalent or better performance in a much smaller form factor.</p>