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Hello! I finally got the Aero Ektar f2.5 178mm lens up and
working on my 4x5 inch box camera that I made. I had an aluminum plate
machined to the thread of the lens, so it provides fine focus adjustment. I
had considered using knife edge focusing by exposing a razor blade on a film,
and drilling a hole through a cheap 4x5 holder and looking through the back, but
instead, I used a Hartman mask to find focus under red, blue, green, and yellow. I have been using TMax 400 film, and developing it in TMax RS.
The Sagitarius star cloud looks good. I pushed the development to an ISO of
3200 according to the TMax RS directions. No grain visible! However, the lens appears to have quite a bit of coma at
f2.5, so I’ll have to stop it down. Too bad, though to be expected with
a WW2 surplus lens. Once I find the best f-stop, I’d eventually like to
try some color instead of B&W filter work, but none of the camera stores here
in my small Australian outback town here can do anything with 4x5s –
B&W or color. I’ll post some of the results when I get something
worthwhile. Best regards. Mike --- |
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