(almost) Infinity-focused Optiphot trinocular heads
Nikon Optiphot (CF) M Plan & EPI objectives have 210mm tube length.
Only “F” trinolar head focus objective rays at 210mm;
“T” and “UW” heads have a pseudo-infinity space around prisms:
Nikon’s CF PL chimney has an M50x0.75 external thread and positive lens.
Removing that chimney allows the infinite image to continue…
Alternatively, removing that negative lens would focus infinity objectives,
but with a bit under a 0.5x magnification
200mm zoom telephoto
A camera with (250mm) telephoto lens focused at infinity,
as discussed on photomacrography.net:
… captured these images:
stainless millimeter rule
same target as below
… however those strongly vignetted images are magnified about 3X
relative to oculars (image by iPhone):
This issue is addressed as T / UW “direct” projection
and arguably better using a Zeiss Triotar.
Other
Other Optiphot infinity configurations
- Infinity objectives thru trinoc “F” head to an infinity-focused tube lens
Eclipse infinity heads reportedly fit Optiphot via Optiphot 100 vertical illuminator. - Optiphot 100/150/200 were infinity scopes with otherwise seemingly incompatible infinity objectives, presumably NOT being CFI60.
- UM-2 measurescope takes Optiphot style nosepieces