Re: Pinhole mounted in bodycap on EOS cameras

----- Original Message -----
From: "Rune Tallaksen" <tallaks@alfanett.no>

> How do I measure the distance from the filmplane til the pinhole?

Here is what I did to measure the same in my Nikon camera, before I got hold of
the Nikon specs: Make a hole 1/2" or so in the center of your bodycao, mount
that bodycap on the camera'd body, set the camera for the maximum exposure time
it allows (30 secs in my case), press the shutter, take a cotton swab and insert
it thru the bodycap hole until it touches the film plane, make a mark on the
cotton swab at the height where the pinhole would be installed, remove cotton
swab and measure the distance with a rule.

Children, don't try that at home!!

Nikon cameras have a distance of 46.5mm from the film plane to the lens flange,
Canon EOS have a distance of 44mm.

> What will the optimal pinholediameter be?

It depends which formula you use. anywhere from 0.009" to 0.010" would be fine
for an "optimum" pinhole, if that is what you want.

> Will my built in exposure be able to measure the light and set a
> "correct" exposure?

It should, under bright light with relatively fast film. It really depend on
the EV sensitivity of the EOS meter system.

> What else should I think of?

Stop thinking, do it and try it, it works!!

Guillermo
Received on Fri Aug 16 23:13:48 2002