Nikkor 800mm f12 T-ED Covers 7x17?

[Paul Schilliger]

A quick try onto the wall show an image circle of at least 40cm for the 800 and 1200. If you are shooting color, you might run into color fringing though beyond the specified image circle. However, with the small enlargement factor that this format will require, it should remain unnoticed on the print. Good luck!

[Kerry L. Thalmann]

There seems to be some difference of opinion on this matter. And while I find it a bit hard to believe that Nikon made more than a couple production runs of this lens, I'm wondering if there are indeed differences in the construction of some 800mm T-ED Nikkors.

Specifically, the rear cell of my 800mm lens has a black circular disk with a round opening that looks like some sort of field stop. I'm wondering if everyone else's 800mm has this same disc. I didn't actually attempt to stick my calipers down inside the lens (didn't want to risk damaging anything), but on my lens the disk is located approximately 1¼" from the front of the rear barrel and the opening in the disk is approximately 1½". So, do all 800mm T-EDs have this disk/field stop? If not, I'm wondering if it's possible to have it removed to increase the coverage of the lens (not that I intend to attempt to remove it myself).

Kerry

[Eric Leppanen]

Kerry,

While I no longer own my Nikkor 800T, my recollection was that, when applying front rise and staring through the front of the lens to see if I could still make out the edges of the ground glass, my 800T seemed to have a similar circle of illumination to my 800mm APO Tele Xenar convertible (which has a 480mm rated image circle). I did a few test shots for edge sharpness with movements, but alas, I cannot find them nor can reliably recollect the results. I'm sure the lens is good for at least some movement, as I used to apply some rise/fall to compensate for pressing a long lens support arm up against the underside of the front standard (to stabilize the camera, which I found absolutely necessary when using this lens).

Looking at my Ebay sale photographs of my 800mm rear element, I don't see any black circular disk. It looks like clear glass extended all the way to the barrel. I will separately email you a photograph of the rear element for comparison.

I'm 99.9% sure you've long ago thought of this, but how much shift capability do you have with your existing 4x10 or 8x10 cameras? Can you achieve 2" or more of shift so you can take a test shot of what would be the edge of an 11x14 negative?

[mohan]

hello Kerry and all!

So, what is the final word on the lens... Does it cover the 7x17? And what is the "real" image circle spec. of this lens?

Thanks

Mohan

[Tom Duffy]

For what it's worth, I use the 600T, which is supposed to have the same image circle as the 800 and 1200 Nikkor. It barely covers 8x10. I use it with the 5x7 format, primarily.

[asnapper]

Kerry,

I purchased a 600/800 T-ED off eBay here in England a few months ago at a bargain price. I use the lens on my 10x8 but I have put it on my 14x17 camera & it looks to cover okay. If the wind is not to strong at the weekend I will expose some 14x17 film & report back with my findings.

Andy