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Really impressed by both Nikola and Sandeha's work; cameras and photos. The gold bellows camera is a gem...
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 Originally Posted by Sandeha Lynch
Two I made over Xmas ...
both look great, but really like the first one... and gold bellows? how terribly decadent, that must turn some heads down the mumbles
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I'd like to solicit the opinions of all the skilled camera builders here.
If you were to build a "one-shot camera", how would you go about it?
A one-shot (tri-color) camera takes 1 exposure but exposes 3 negatives at once by splitting the light with 2 partially silvered mirrors. Let's assume the mirrors are easy to get and that the geometry could be easily calculated. How would you achieve the precision & rigidity to assemble something like this? Would love to here your thoughts.
Some inspiration here -> http://www.vintagephoto.tv/bermpohl_img.shtml
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the mirrors are easy to get. Check here.
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Indeed, thanks for the link. 5x7" mirrors are $100 a piece. Doable if you could figure out the rest easily enough.
A great design would be something that uses 3 6x7cm backs so you could have roll-film capabilities, in which case you could use the 75mm² mirrors.
Also, I think that any design using glass mirrors, as opposed to ultra-thin pellicles, would require other clear glass in the optical path to negate ghost reflections from the light passing through 2 surfaces per mirror, but Edmund's have AR coatings that might(?) obviate this step.
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I've been involved in this with cine 16mm - but not using beam splitters ...
Prob best to start a new thread on it as to keep this one one topic (post pics of your camera here, once you've built it)
But yeh, you'll need a 2/3rd 1/3rd split mirror for the first split then a 50/50 for the second (1/3 goes to the first film, then %50 of 2/3's i.e. 1/3 to the other two) - then you'll need your three wratten gels or filters with quite a hefty intensity reduction in each to split the colors adequately, Hope you're not planning on photographic moving objects ? exposure might be too long - if not then consider using no splitters, and changing filters for three consequtive shots instead (what was done in 16mm). Have a look into Kinemacolor also.
As for precision & rigidity- where to begin !
um, just - er, - hrmmm - build it well ??
ok, think about this: while you are building the camera think about the process of verifying its output in terms of the output specifications you're after, once you're happy - you're happy - happy is happy = done...
If not, then look at what you're not happy with a deduce what is causing it, then fix it.
Every camera has faults - it's how picky you are that defines them
Long winded way of saying that maybe we can help with specifics once you hit a specific problem, but for now, it really is too hard to give advice. Hopefully someone will prove me wrong ?
btw, googling 'one-shot camera' and having a quick glance doesn't give any related hits
edit: just had a look at Edmund optics - interesting they dont do a 66T/33R or 33T/66R splitter huh ? And yes, go with the AR coated ones if you can - mind you, the natural responce of the filters involved will probably solve any bounce back issues - something to ponder
Cleared the bowel problem, working on the consonants...
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Thanks Nick,
You're probably right about keeping this thread sacred. Well if there's any interest, please go to this thread, where you'll see a lot of information on tri-colour cameras (there's about as many ways to refer to them as there are optical paths!... argh!)
I'm not outfitted to build any kind of camera, unless it's built of balsa wood or popsicle sticks, or something. I'm hoping that the "brain-trust" exemplified in this thread might be able to come up with some clever ideas if prompted.
Last thought; the bounce back problem is actually a problem of refraction. Since there is thickness to the mirrors, and the light enters them at angles, some of the light will be separated by a distance equal to the thickness of the glass. Or at least, something to that effect...
thnx!
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Looks like that thread is where all your info is ?
I dont think balsa and popsicle sticks are going to get you far with this - but you're probably saying that in jest ? Why not start with a simple fixed infinity focus camera first, maybe even a pin hole with a 4x5 back or something - it'll get you going, do you have access to any workshop ? I picked up sooooo many ideas from watching other people work, tools that looked like a mystery in the shop all of a sudden have purpose very particular to my needs...
Years later and here I am with a auto tool changing 4 axis CNC VMC - yes, you'll need one of those soon too
Cleared the bowel problem, working on the consonants...
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Definitely in jest... 
Point is, I'm not asking how to build, I'm just asking for ideas from builders. Afterall, collaboration, specialized knowledge, outsourcing different operations... aren't these things the future of industry?
I'd love a workshop, it's just not an option in my life right now. However... I like the idea of a one-shot pinhole...
p.s. In that thread, you might be better off starting at the end and working towards the beginning; more links, pictures and stuff back there. I'm just trying to put all the related stuff I can find in one place.. with a solid dose of meandering conversation.
Cheers!
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