Quote:
Originally Posted by Rigel003
Greg, can you suggest a lens (preferably older and cheaper) with enough back focus that would work with the FLI CFW-2-7 and ML8300? I think none of my current canon lenses are suitable.
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Pentax 67 lenses. 165mm F2.8 is good, 55mm F4 shows a lot of coma wide open but works 2x2 binned, 300mm F4 (there is a 300mm F4 ED IF which is a super lens but its $1500-2000 and rare).
You'll need an adapter made up from a Pentax to Nikon adapter which Precise Parts then fixes to a FLI CFW fitting.
I use a FLI PDF focuser in between lens and filter wheel. As even though you can manually focus these, the pdf gets the exact focus which is hard to get exactly manually.
I did see table on a site once that listed backfocus distances of different lenses. Pentax 67 were around 87mm but there were a few others like that. I'll see if I can find that.
You also get a FLI Nikon filter that fits the CFW but that would mean manual focus or you setup a Robofocus, a bracket to mount it on and a belt that wraps around the focus ring of the lens and this takes up no backfocus.
I found a couple of tables of backfocus distance:
http://en.wikipedia.org/wiki/Flange_focal_distance
http://allphotolenses.com/articles/item/c_6.html
Greg.