New Old Nikon 35mm 2.0 D

[kin_ho]

<p>You put a zoom lens on the camera ... I think twice about taking it with me. You put a 35mm F2 on the camera and I don't care even if I don't come back without shooting it as it so light.</p><div></div>

[tom_mann1]

<p>Kin, I understand your point, and often feel the same way, but I think you posted the wrong image to illustrate your point.</p>

<p>Not only is is the image you posted not taken with the lens we have been discussing, nor is it the lens you thought it was, it is actually a modern zoom with decent performance that I bet would beat the old 35/2 especially at the edges of a FX frame when zoomed to 35 mm.</p>

<p>FYI, the EXIF info for the image you posted says that it was taken with a 24-85 f/2.8-4 at FL=24 mm and f/2.8.</p>

<p>Tom M</p>

[elliot1]

<p>There is no question that the extreme corners are not the best with the 35mm f2. For many typical shots, the corners would be out of focus anyway and not really matter. Otherwise mine does a great job, sharp through most of the frame.</p><div></div>

[elliot1]

<p>Same shot with 35mm f2 lens</p><div></div>

[elliot1]

<p>Looks sharp to me...</p><div></div>

[elliot1]

<p>I find the lens almost as sharp wide open as it is stopped down.</p><div></div>

[elliot1]

<p>The above test shots were shot with the D800 on a tripod, all at ISO 100. Exposures varied from 1/2 second for the f2 shot to 6 seconds for the f8 shot.</p>

[tom_mann1]

<p>Hi Elliot. Thank you for the interesting systematic comparison shots of near-center sharpness over a nice range of f-stops. Real data like this is always wonderful to see (ie, instead of blanket assertions made without such data).<br /><br />At least in my mind, there has never been any question that the 35/2 AFD is quite sharp in the center, even wide open. In fact, on July 12th, I made exactly this comment in http://www.photo.net/nikon-camera-forum/00VfPT: <em>"...but the center remained reasonably sharp, even wide open - a look quite different from say their 50/1.4 AFD wide open (of the same vintage) ..."</em>. <br /><br />If there are any differences of opinion about this lens, I think they arise mostly because of different intended uses and expectations for a lens like this. If one wants a light-weight, moderately wide lens for landscapes with a tripod, it will be absolutely fine because landscapes are usually done with the lens stopped down to the optimal aperture for sharpness or even smaller, if extra DoF is needed. <br /><br />In contrast, I think of f/1.4 and f/2 lenses mostly as handheld available light specialists, and hence, I am most concerned about their performance when wide open. In some of these situations, one doesn't care in the least whether the edges of the frame are soft. This may be because either (a) you want soft edges (eg, http://farm5.static.flickr.com/4144/5071317673_3e004d8054_z.jpg posted in http://www.photo.net/nikon-camera-forum/00XX8p), or (b) the limited DoF at wide apertures is going to completely cover up any lens aberrations that are present. We all have examples of category (b) shots. The example you just posted falls precisely into this category, as does the photo I attached below . <br /><br />(continued in next post) <br /><br /></p><div></div>

[tom_mann1]

<p>(continued from previous post)</p>

<p>However, there are many situations where one wants to use as large an aperture as possible, and DoF is not going to cover up the elongated blur shapes this lens produces as you get near the edges of a (full) frame image. The 1st example that comes to mind is shooting short exposure time pix of stars (ie, where you want points of light in the sky, not star trails). Another example that comes to mind is shooting news at night. In this case, your subjects (think rioters / police) may be several or more yards away (so blurring from limited DoF won't be a big issue), and are likely moving (so you need as high a shutter speed / wide an aperture as possible). If street, auto, and other lights near the edges of the frame all come out as ellipses, it's going to look odd and unprofessional.<br /><br /><br />BTW, NBD, but in the example(s) you just posted, the EXIF info shows the lens you used to be a 24-70/2.8, not a 35-70/2.8 as stated in the captions. <br /><br />Cheers,<br /><br />Tom M</p>

[kin_ho]

<p>Stupid me for posting the wrong picture. Down sizing to post on this site is a little bothersome.<br>

But here is one I took earlier on in the day. 35mm F2.0D at F2</p><div></div>

[tom_mann1]

<p>Hi Kin - No problem. I've done the very same thing myself. </p>

<p>Since the resolution of photos posted here is limited to 700 pixels in the longest direction, it's almost impossible to see aberrations if one posts the full image. Can you post a crop of that image that is say, 600x600 pixels from the lower left corner? That would be much more informative.</p>

<p>Thanks,</p>

<p>Tom </p>

[kin_ho]

<p>Ok I will try but my cropping accuracy is not assured.</p><div></div>

[elliot1]

<p>Tom, thanks for catching that. Yes, it was a typo and I did indeed use the 24-70mm f2.8 lens. Sorry all for the error.</p>

<p>Kin, that corner actually looks pretty good.</p>

[kin_ho]

<p>Yeah I think photographers worry about lens spec and sharpness to such an anal extent it prevents newer photographers like myself from buying glass that is more than acceptable. For me it's about wanting to take my camera out and use it. It doesn't matter if I can afford a 35mm 1.4G or not at 600g it's heavy and it gets in the way. I can can actually tuck the 35 F2.0D under my arm and walk as if nothing is there.</p>

[tom_mann1]

<p>I haven't forgotten this thread -- I've been experimenting with my 35 f/2 AFD in an attempt to get to the bottom of this difference in perceptions about this lens. One of the things that I observed is that there is a substantial focus shift with the lens as you stop down from f/2 to f/5.6. Since AF is always done with the lens wide open, this could explain some of the softness at other apertures. More later.</p>

<p>T</p>

<p>PS - Rather than posting crops (Kin was nice enough to do), I would like to post some full resolution images from the tests I've been running, but I don't think photo.net will accept such large files. Any suggestions of where to post these so that they are available to other participants in this thread?</p>

[elliot1]

<p>Tom, you can try Dropbox.com</p>

<p>What kind of focus shift are you experiencing?</p>

[kin_ho]

<p>I always use flickr. I don't mind cropping it's just that I don't know if it is accurate or not. e.g. is it a 100% crop I don't know and there is also a lot of down sizing with photo.net so all the pictures are of a low resolution.</p>

[tom_mann1]

<p>I'm back. I just noticed that in a couple of other threads, people were able to post full rez images. Their images weren't displayed in-line, only with links, but if you clicked on them, you saw the full rez version, so I'm going to try the same thing in this thread. If it doesn't work, I'll set up a Dropbox account and give everyone access.</p>

<p>Last night, I took a number of 30 second exposures of the house across the street. Many objects in the frame were all effectively at infinity. I did these experiments at night using time exposures mostly because (a) that was the only time I had available, and (b) because darkness made it a bit more convenient for me to use the rear LCD to tweak the focus using Live View mode.</p>

<p>I put my d700 on full manual mode for both exposure and focusing. Obviously, I used an *extremely* sturdy tripod - my old Tilt-all that can easily hold a 4x5 LF camera at full extension. I didn't use standard mirror lockup mode on my d700 because (a) any vibrations induced by mirror movement settle down quickly on the scale of a 30 sec time exposure, and (b) I don't think standard mirror lockup mode can be used with live view on the d700, because the mirror is already raised for Live View.</p>

<p>The two images presented below are the JPGs straight out of the camera. They are at equivalent exposures: One at f/2 and ISO=200, and the other at f/5.6 and ISO=1600.</p>

<p>The focus point in both cases was the bright light that is dead center in the frame. The focus for each was tweaked separately using Live View. In the 2nd case (ie, f/5.6) I stopped the lens down to focus. There was noticeable focus shift when stopping down. As it turns out, at f/5.6 and smaller apertures, the optimal focus as determined by Live View had the focusing mark on the lens lined up exactly at infinity (to within less than one line width). In contrast, at f/2, the optimal focus as determined by Live View had the focusing mark on the lens about 1 or 2 mm nearer than infinity.</p>

<p>While I was experimenting with focusing issues, I also tried using conventional single AF mode, and using manual AF (non Live View), but using the green focus confirmation indicator visible in the viewfinder. I was a bit surprised and certainly pleased to discover that both of these methods produced exactly the same focus as manual focus tweaking using Live View.</p>

<p>Here is a list of some of the things that I observe in these two images:</p>

<p>a) There is considerable light fall off towards the edges of the frame at f/2. However, in the center of the frame, there is little difference in brightness between f/2 and f/5.6.</p>

<p>b) Diffraction from the blades of the iris is obvious at f/5.6 on the bright lights. Obviously, these are severely over-exposed point sources, so they exaggerate diffraction, but the effect is clearly there at f/5.6 and not there at f/2.</p>

<p>c) The bricks on the wall of the house (just to viewer's right of the central light source) are sharper and more contrasty at f/5.6 than at f/2.</p>

<p>d) Distant objects near the center of the left edge of the frame are *much* sharper at f/5.6 than at f/2. These include the parked silver car and the fire hydrant (between the stop sign and the tree), the leaves on the tree beyond the parked silver car, etc. Nearer objects in the same part of the frame (eg, the Washington Post writing) don't seem to benefit as much from stopping down.</p>

<p>Initial conclusions:</p>

<p>1. Don't assume that normal auto focus mode will produce optimally sharp images. The lens is fully open for focusing, but when closed down to take the shot, there is clearly a focus shift.</p>

<p>2. This lens, like all others benefits from stopping down.</p>

<p>Final conclusions? ... I'm not quite there yet. In particular, I'm very suspicious that the lens behaves differently with closer objects, eg, the xmas lights, the dual LED headlight tests at about 4 meters, etc.. I'm also quite sure that point sources of light in front of the surface of optimal focus have very differently shaped blur patterns than objects on or further than the surface of best focus. Stay tuned.</p>

<p>Tom M</p>

<p>PS - I don't know about you, but I'm learning a lot about this little lens!</p><div></div>

[tom_mann1]

<p>... and here is the same shot at f/5.6 with the Nikon 35 f2 AFD...</p><div></div>

[elliot1]

<p>Can you elaborate on exactly how the focus is shifting (conclusion 1)?</p>

[tom_mann1]

<p>Hi Elliot - I'll be happy to elaborate, but I'm not sure what detail I missed about focus shifting in this paragraph:</p>

<p><em>"The focus point in both cases was the bright light that is dead center in the frame. The focus for each was tweaked separately using Live View. In the 2nd case (ie, f/5.6) I stopped the lens down to focus. There was noticeable focus shift when stopping down. As it turns out, at f/5.6 and smaller apertures, the optimal focus as determined by Live View had the focusing mark on the lens lined up exactly at infinity (to within less than one line width). In contrast, at f/2, the optimal focus as determined by Live View had the focusing mark on the lens about 1 or 2 mm nearer than infinity..."</em><br>

<br />Let me know what I glossed over and I'll try to fill in the blanks.</p>

<p>Tom M</p>

<p>PS - It just occurred to me that perhaps you want to know my definition of "best focus" (ie, in both the f/2 and f/5.6 cases)? If so, I must confess that I obtained "best focus" in each case completely by eye (ie, like a photographer, not analytically like an optical engineer or physicist might do). If pressed for more details, I would say that I always attempted to minimize the area of the OOF blob by slowly, manually rocking the focus back and forth while watching the image on the rear LCD. When it seemed that I had achieved the smallest area of the blob, I called that the point of best focus. When doing these measurements, I always had the Live View zoomed in to the maximum possible amount -- ie, largest available magnification.</p>

<p>If I would then use a different aperture and perform the same procedure, the final, optimized focus position of the lens barrel (as indicated on the distance scale) would be different by as much as a couple of mm. This is essentially THE definition of focus shift.</p>

[kin_ho]

<p>I don't know about all this focus shift malarky but both photos look great to me although stopping down the aperture does give a sharper picture but we knew that already? </p>

[tom_mann1]

<p>Kin, I agree with you that my two most recent images look pretty good - they are much like the image you posted. In fact, your cityscape image prompted me to photograph the night scene that I just posted. I did this because I was suspicious that the lens behaves differently at (or near) infinity compared to it's behavior at more moderate distances (ie, my previous tests). In fact, it now looks like this suspicion is confirmed.</p>

<p>It should be obvious to anyone who has been following this discussion there is much more going on with this lens than is revealed by this particular pair of images. For example, don't you recall the highly elongated and highly distracting blur "circles" that I posted in these two threads:</p>

<p>http://www.photo.net/nikon-camera-forum/00VfPT and<br>

http://www.photo.net/nikon-camera-forum/00YtO1.</p>

<p>To me, if a lens produces images (under some circumstances) that make other photographers think I spun the camera or used a crude post processing effect, I will be very careful about using that lens for general photography.</p>

<p>This is why I said, "Stay tuned". As time permits, I'll continue to try to figure out how all of these observations relate to each other.</p>

<p>Tom M</p>

<p>PS: Just in case you weren't aware, <em>"malarkey"</em> is a derogatory term, and you almost certainly wouldn't like it applied to yourself. </p>

[tom_mann1]

<p>OK - I'm done for now. I think my "OOF blur shape" explanation (that I hinted at in a couple of previous posts) completely reconciles the fairly sharp images at f/2 that several people (now, including myself) have reported, with the strangely shaped highlights in my original photo of xmas lights ( http://static.photo.net/attachments/bboard/00Y/00YtlW-369903584.jpg ) and the tests with my LED headlight (acting as a quasi point source) in a darkened room.</p>

<p>Attached below is a series of 100% crops of the distant yellow light that was in the dead center of the frame in the two full rez images that I posted last night. The difference is that tonight, I put that light in the extreme corner of the frame and took a series of shots as I manually focused the lens from slightly beyond the infinity mark on the barrel (1st image in the upper left corner of the array of images) down to about 2 meters (3rd row, 2nd column). The f-stop (f/2), ISO and shutter speed were all unchanged over this sequence of shots.</p>

<p>When the focus distance indicated on the barrel of the lens is larger than the actual distance, the light produces the oddly shaped double crescent blurs seen in previous images that I've posted. As you focus in, the size of this blur decreases, and at the point of best focus, the blur shape is the smallest and happens to be somewhat X-shaped. As you continue to focus closer, past the point of best focus, the blur shape becomes nicely round.</p>

<p>My conclusion from all of this is that if your subject is either nearly flat (and you are perpendicular to it), or is nearly at infinity, this lens can produce reasonably sharp images, even wide open at f/2. HOWEVER, if, as in many low light people pix, there are objects in the frame that are closer than your subject, be prepared for these objects to exhibit some strange blur effects, with the worst case being nearby point sources of light (as in my xmas light photo).</p>

<p>All in all, I could do without these weird OOF blur patterns. The problem with this lens reminds me of the classic OOF doughnut problem with mirror lenses. When I get a chance I'll check out some of my other old wide angle lenses, e.g., 20/2.8 AFD, 28/2.8 AIS (close focusing model). If anyone following this thread has a new 24/1.4 or 28/1.8, it would be great to know if this effect is present to this extent in the newer models from Nikon.</p>

<p>Cheers,</p>

<p>Tom M</p><div></div>

[elliot1]

<p>Tom, I have not used the lens as extensively as you so I am trying to understand the issues with it to better understand its complexities. I reread the focus shift info you wrote. When the focus shifts, is the 'correct' focus point shifting as well or is the lens focusing incorrectly even though it indicates it is focused correctly.</p>

<p>Your 'astral photography' images above (thought the first few were views of Saturn) shed a lot of light (pardon the pun) on the strange OOF area characteristics of this lens. And certainly helps explain your previously posted light photo. Have you tried the same test with any of your other known good lenses? Does stopping the lens down without changing focus correct or partially correct this issue? It appears to be a very odd phenomenon and certainly warrants extra care when using this lens under specific shooting situations.. </p>