Re: Window placement

[P3D Alexander Klein <klein@xxxxxxxxxxxxxxxxx>]

P3D Dr. George A. Themelis <fj834@xxxxxxxxxxxxxxxxxxxxx> writes:

> Paul Talbot, the tireless mounting investigator writes:
> 
> >and in digest 1953 "pack rat" Alex dug up an interesting table that
> >included measured gate widths on a variety of 3D cameras.  The Kodak
> >was measured at 22.76mm; Revere 23mm; Realist 3.5 at 23.45...
> 
> I love the 1/100th mm accuaracy Alex! :)

I'm using a caliper which is accurate to 1/100th of a mm - why not use
it?

> >images from Revere, and especially Kodak cameras,
> >might not have as much range of window placement flexibility as DrT's
> >Realist?  I have noticed that Revere chips seem to have less room for
> >adjustment in the mount compared to Realist 3.5 chips...
> 
> Interesting observation Paul... I think you are right... Perhaps
> there is more gap between the Kodak/Revere chips, compared to the
> (non-existing, or occassionally negative :)) gap in Realist chips.

Which means that one has to be very careful about measuring things: the
image width that counts is the one where only one image is visible (ba-
sically, an area where two images overlap on the film can be considered
"black areas").

All the Realist format cameras move the film by 10 sprocket holes. Each
two sprocket holes are 4.7500 mm apart (according to the standard), which
means that there are two images per 47.500 mm, which allows a maximum of 
23.750 mm per image. So there _should_ be no problem, even with Realist
chips (but of course there is).


> In Alex's table I noticed a variation in the gate height too.  For example,
> the Realist has 25.3 mm height while the Belplasca has 24 mm and the FED
> 23.6 mm.  I have noticed that when I mount Belplasca chips I hit the black
> (outside image) area when I push the chips all the way up in the Albion 7p
> mounts, while I have never seen the black area in a Realist chip.  At first
> I thought that this was a result of the Albion 7p vs. 5p dimensions but now
> I see how it can be due to the difference in image size.
> 
> Hmmm... more Realist advantages... :)

You could still use a file and enlarge the gate height. Although this means
cannibalization of a camera - to which I clearly object as a collector-user.

alex

http://www.stereoscopy.com
Ph. +49 (172) 6072247


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