Making an interchange-able 4x5 camera back

[minhnguyen9113]

I just finish the 1st and 2nd steps of making an interchange-able 4x5 camera

back and I need some suggestions from the forum

I want to make a film holder housing but it so difficult to bend it 6 times, so

I decide to make 2 film holder brackets, this way I can use a ground glass to

set focus

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The interesting of this back is when you mount it to a camera with a ranger

finder, it will be a 4x5 ranger finder camera, mount it to an electric eye

camera it will be a 4x5 electric eye camera...

 

Really need your suggestion to make it work right, and welcome everyone to try

if you have one. The back is less than 1lbs, the body without those heavy junk

is 2lbs, the whole 4x5 camera is less than 3lbs.

 

Thanks, Minh

[patrick j dempsey]

Cool idea Minh! Most people cut into the camera and add the film holder in place of the door, but this would actually turn the camera into a closeup camera!

 

I'll start thinking about this route and send you some drawings if I think of anything.

[patrick j dempsey]

Have you considered using 3 peices of extruded aluninum "C channel" or "U channel" instead of sheet metal? They might have some at Lowes that the 4x5 holder will slide into? That could be bolted to the body, but would only be good with a specific thickness of film holder.

[patrick j dempsey]

Another thing... take notice of the position of the viewfinder window, on my Model 150, a centered film holder would run into it.

[minhnguyen9113]

Patrick

 

In that case I'll ask the view-finder share room with the back and both will be happy. Thanks

[joanne_lax]

Minh and Patric,

I've been thinking along the same lines past couple weeks.

 

Lets say the new film plane is 1" further back from the original. Will the rangefinder read accurately if the front lens standard is moved back an equal amount? Seems it should...

 

Health, Peace out

 

Joanne

[minhnguyen9113]

Joanne

 

It moves back about 3/4", but we can set infinitive focus so

I don't think it makes any different, mine is almost done.

[patrick j dempsey]

Yes Joanne... I think one method is to remove the existing catch that is at the end of the bed and put a new one the exact same distance back as the film plane has moved back. You probably want to test this against the ground glass and not just go by measurement... but this will allow you to keep the rangefinder without any changes to the rangefinder itself or to the lens. I've got a Polaroid 545 back that is itching for me to do this conversion and order some Pola sheet film! I'm wondering if there would be a way to use this setup to do macro work since you could theorhetically use the original top in conjunction with a new stop, perhaps adding a second focus scale for macro focus distances?

[minhnguyen9113]

Patrick

 

How about a Polaroid MP4, That really a good one for macro work.

 

I move the catch back about 3/4" and use ground glass to set it right, but I find out the film holders are different in sizes a little bit, some are thicker some are wider, about 1/8" ...Let see how does it work.

[patrick j dempsey]

MP4 is pretty awesome... I'd love to carry one around as a portrait camera... but I'm thinking more and more about doing one of these 4x5 hacks, can't wait to see your results!