Author Topic: Quickdisc bellows extension calculator  (Read 176 times)

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Francois

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Quickdisc bellows extension calculator
« on: September 27, 2017, 03:03:16 PM »
We all know how annoying doing close-up photography with a view camera can be.
Granted you can focus really close, but that involves compensating the exposure for the additional distance the light has to travel before hitting the film.
Well, here is a simple solution to the problem.

http://salzgeber.at/disc/

Just print, cut and use as directed
Francois

Film is the vinyl record of photography.

jojonas~

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Re: Quickdisc bellows extension calculator
« Reply #1 on: September 27, 2017, 09:43:31 PM »
I guess the thingie I posted in that meter thread goes better along here :)

I wonder if anyone has tried to make a home made extinction meter?  It seem like it could be fairly simple.

how about an extention meter? ;)

for large format shooting

Print, mount on cardboard (if you want), cut out and put together in the middle with something that makes it spinable. When focal length 75 is readable on bellows output 75, the blue arrow will end up at 1, ie exposure time times 1 (focus on infinity). If you spin the disc and 75 end up with about 140, then there will be 2 stops or factor 4, where the blue arrow will end up (scale 1: 1). And so on.
/jonas

Francois

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Re: Quickdisc bellows extension calculator
« Reply #2 on: September 28, 2017, 01:25:45 PM »
Yeah, that's another good one.
Francois

Film is the vinyl record of photography.

ManuelL

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Re: Quickdisc bellows extension calculator
« Reply #3 on: October 13, 2017, 06:09:42 PM »
I am just using a measure on which I added marks for the extension stops on the back side for some of my lenses. Very simple and no calculation required.