D200 Non-CPU Lens Data - 75-150 Series E

<p>I just picked up a <strong>Nikon 75-150 f/3.5</strong> Series E lens. I plan to use it with my <strong>D200</strong>. However, I can't figure out how to enter the focal length in the Non-CPU lens data menu. <br>

I have used Non-CPU lenses on my D200 before but this is the first zoom. I did some internet searching but couldn't find answers so I am hoping that someone can give me advice. I saw that some people simply enter a focal length in the middle of the range - like 105 maybe in this case. It would be nice to find a more elegant solution.<br>

I know this is a popular lens, so if you use it on a DXXX or DX body, maybe you could share your approach?</p>

<p>Thanks. </p>

<p>I don't think you can. However since the lens is not a variable aperture lens it does not matter. I believe that the only thing that is important is the f3.5, otherwise enter any focal length that you will remember as being associated with the lens.</p>

<p>Thanks Phil, that is what I was suspected. If that is the case, I guess the follow-up question is: what is the practical effect of this? As you point out, the aperture is not variable so that isn't a problem. So is it just a matter of having accurate EXIF data, or is there some tangible effect on camera/lens function - metering for example?</p>

<p>Just the EXIF data as far as I know, there is no effect on exposure.</p>

<p>Some algorithms use lens focal length as a best chance substitute for unavailable lens focus distance information (D), so you better enter value that is usable in this lens, e.g. 75 or 150.</p>

<p>On zooms I usually split the difference on focal length--like halfway between 75 and 150. Seems to work OK. On both my manual zooms the aperture is constant.</p>

<p>My 75-150 has a custom-programmed CPU. Thus, EXIF will declare it correctly as being "75-150 mm f/3.5-32 P". You can set aperture directly on the lens, or dial it in from the camera. All exposure modes (A, M, P, and S) are available and light metering will work with all current Nikons. However, as there is no feedback from the lens with regard to the focal setting, an assumed focal length has to be chosen. Based upon trial and error, for zooms I select the average focal length (nearest EXIF value is 6C or 112 mm in this case ) and the corresponding max.f-number at that focal setting (f/3.5 for the 75-150 of course since it has constant aperture all over its range; for variable-aperture zooms I calculate it from actual light metering). Together with the exit pupil information (sent by the CPU) this ensures excellent results from the matrix metering.</p>

<p>Thanks everybody. I tried using 105mm and that seems to work well enough. Without inputting a focal length, I was getting significant under-exposure.</p>

<p>Oh, and one more follow-up on the 75-150:</p>

<p>It is in great shape with the exception of a little oil that is showing on the aperture blades. I know this is something that can become a problem with the blades sticking and with oil dripping on the rear element so I will probably want to address it at some point. Is this the kind of thing that can be fixed with a standard CLA or is it a bigger job? </p>

<p>If anybody works on these 75-150's regularly, feel free to shoot me an email and I'll keep you in mind for the work.</p>

<p>If I were you I would NOT use 105mm as the dialed-in focal length. I would use the 70mm or 86mm focal length. The focal length is put into the EXIF tag, so if you have a 105mm 2.5 lens (and you really owe it to yourself to have one) then it becomes harder to sort and find images later on. </p>