kari_oinonen

<p>Tested that with a Zeiss 100mm lens. Possible, propably changing the camera parameters then. Tested only that the value appears as set and stays as set over switching the power off.<br> Dandelion: possible, probably (most probably) changing then the lens chip parameters. There is a separate procedure for that.</p> <p>Testing with your lens is straighforward and recoverable ;-)</p>

<p>Derek, having looked at the forest image (not a crop) at 1000 pixels wide, I'd say I was not pixel peeking. Still there is fringing - way too much. I suppose that the mountain laurel image is a medium crop, but not nearly at 100%. The fringing is clearly visible. When you know it is there, at least you will see it and notice it.<br> If you keep that lens sample - you will start hating it very soon. (If I had known I would have returned my, then current, version of the 20mm lens as the focus plane was tilted - the right 1/3 of the image needed clearly different focus setting compared to the rest of the image.)<br> As with everything, especially with manufacturing and assembly there are tolerances and eventually some samples are produced that are at or beyond acceptability limit. Outliers are bound to happen. Tests after the assemby are not done to every unit produced except for the high end special lenses.</p>

<p>I have the older version of the 20mm lens. My copy of the af-d 20mm f/2.8 has been a trouble. The af-d is supposed to be a lesser lens compared to the 20G. At f/7 af-d is still reasonably good. When testing I have shot a fair share of similar scenes.<br> For the new af-s 20/1.8 G I would expect better behaviour around f/7. <br> SW corrections may help. In Nikon world I have got help from axial CA correction in Capture NX-d. However, too much of the axial CA correction and I start losing overall image colors. <br> What happens to the fringing if you are changing the focus distance?</p>

<blockquote> <p>a flash value lock (which can be recommended where relevant) - uses much more juice than just the indicated flash output value.</p> </blockquote> <p>= FV lock. See the manual if needed. FV lock should be available with your setup.<br> It helps - somewhat - if you turn down the popup output, but still the commander flash pulses may take too much juice. When you use FV lock you do the commander-measurement (preflashes) action only once and the following pops of the SB700 are based on those values.<br> Overall you are using the popup less, so energy is saved and the preflashes are avoided.</p>

<p>Sorry, I was not using the proper Nikon term. Master = the unit that controls other units = commander in Nikon terminology.<br> Test what you can do with the suggested FV-lock. It seems - based on your tests - that the pop-up flash needs too much power and thus recycle time in commander mode. Unfortunately I do not currently have an possibility to make that test.<br> If you set the FV-lock, the systems makes only one preflash-measure -cycle when activated. Then the measured values are used for the the following exposures. Additional preflashes are not needed, you get less flash blinking before following exposures, delay due to commander preflashes is eliminated and power is saved too.</p>

<p>If you need to have more than 12 megapixels, you need another camera or you can use D700 and stitch. What you need depends.<br> Dedicated stitching programs (I have an older version of PTGui - others do exist) can correct well lens distortion parameters. Those parameters get calculated automatically from 2-3 overlapping sample images. Thus the need to hire a T/S lens is lessened.<br> You may want to take some test shots from your target or another suitably similar one, download a test version of a stitching program and see what you can get with that. Try first a low number of images to be stitched, like three or four in one row. By doing a simple row pano from 3-4 overlapping images in portrait orientation you may get around 20-24 megapixels for covering the artwork.<br> For landscape panos I have used 20mm, 28mm and the mentioned 55mm lens mostly.</p>

<p>What has happened to me a least once: I was in a hurry trying to take that shot. The buil-in/ popup flash did not fire. I tried several times with no luck. Finally I turned my hat backwards and it worked. - The peak of my cap was tilting the popup a bit to make it unactive :-)<br> Anything can, and will happen.<br> And one another thing to consider. The master flash mode - unless using a flash value lock (which can be recommended where relevant) - uses much more juice than just the indicated flash output value. This is because master flash is telling the other flash (groups) what to do before each exposure. This communication uses somewhat juice.</p>

<p>If you are controlling the off camera flash via the built-in flash of the D750, then the built-in flash and its recycle time or possibly its overheat protection may be limiting factors.<br> The flash icon in the viewfinder tells the status of the attached or built-in flash.<br> They are recommending a separate devise (su-800 or another master flash) for situatuions where a faster recycle time is needed.</p>

<p>What was your focusing distance, test target, lighting and camera support?</p>

<p>Try to reach the focusing screen tab or the focusing screen edge with a tool or tap the camera slightly and ease the focusing screen out.</p>

<p>The oil or dirt can cause problems even one cannot see oily aperture blades. One week ago I had to open my nice Nikkor 180 ED. Some dirt had accumulated to the moving parts of the aperture mechanism. Aperture blades were ok.<br> This - now corrected - problem came apparent when I was shooting with very small apertures below freezing point.<br> When testing the aperture mechanism by flipping the aperture lever at the lens, I thought first that it is ok. Only after a carefull inspection it came apparent, that there was a small amount of delay in the closing phase. This delay can make things to go wrong.</p>

<p>My intention was to use UV against the mold, not to combat the ozone ;-)</p>

<p>Does your dehumidifier add some ozone, while taking away some moisture? Saw that Robert pointed this possibility too.<br> So far I have lost only two Nikon circ pol filters due to improper storage. Some fogged lenses I have been able to restorate. I had earlier some adhesive tape material inside of my camera bag. Obviously it was giving out material (gas?) that caused problems in the form of fogged glass surfaces. <br> A small uv-light may be effective against mold.</p>

<p>My best guess is that one or some of the lens internal frame screws has got loose. I had a similar issue in another lens (af-d) - from the day one. Finally several years after I tightened that screw. Meanwhile Nikon authorized service said that the lens is in specifications - no it was not, but I trusted them, then.<br> You can allways send the lens in for service. It is also possible to open the mount side of the lens to see what you can do. Zoom lenses are beyond my limit though.</p>

<p>Good news, but the link provided gives me 404 error.<br> While active now: how to upload the allowed three images (Nikon forum) at once - so that A.G. is not sending his great Great Canyon images in between ;-)</p>