Homemade macro camera?

[P3D Greg Erker <erker@xxxxxxxxxxxxxx>]

George wrote:

>There are two basic stereo microscope designs:
>
>1. Greenough
>2. Common main objective (CMO)
>
>In the Greenough system the optics consist of paired objectives and
>eyepieces.  In the CMO system there is a single common main objective.
>Most microscopes are of the Greenough design which is more compact and
>less expensive to make.  I have a CMO microscope at home and I like it a
>lot.  It has a huge objective and the quality of the images is excellent.

  This makes me wonder about making a closeup camera with only
one lens. I have an medium format camera (Ricohflex TLR) with
an 80 mm lens. Would it be possible to put a divider from just
behind the lens all the way to the film plane to divide the light into
left and right halves. After developing cut up the film chips and
mount them in Realist 5 perf or 7 perf mounts ("Oh no!" exclaims
orthoman :)

  The lens is f3.5 so the diameter is about 20 mm, so the center
to center separation of the two half lenses will be about 10 mm.
This only would work wide open since as you stop down the aperture
gets narrower and the effective separation gets smaller.

  But I could make a piece for the back of the lens with two
small holes (say f/16 and 10 mm apart) then always shoot with the
camera diaphram wide open. F/16 would allow sunny 16 outdoor shooting
and work well with flash at short ranges.

  With a +3 or +6 diopter lens in front, the subject distance would
be 12" or 6" which would work well with the 10 mm "lens" spacing.
Cropping Realist size pieces out of half a 6x6 image should allow
for some errors in framing.

  So is this a cheap way to get a "Macro Realist"? Or are there
some problems due to not using two lenses (ie prism effects from
having the image come off center thru the lens)?

Thanks - Greg



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