Process Camera to ULF

[icywarm]

ok I spent 6 hours on Sat taking apart a process camera... now I have 4 foot bellows, a negative plate and ground glass at least 30"x30" and two lenses 160mm and 205mm.

I have sketched out a three wheel base system, but I need the math for where and how big to make stuff... and good camera math resources on the web?

Shutter is also going to be an issue... I am thinking of build a couple sized film backs... one being able to hold a X of 120 to test this thing...

Ap is controlled on the lenses and they are mounted on lens boards that tension fit on the bellows....

It is going to be big, ugly and fun....

[icywarm]

I found Jon Grepstad website and book... seems good... just need an idea for a shutter....

[dsphotog]

Great project!
Try a search for Packard shutter.

[icywarm]

Great project!
Try a search for Packard shutter.

perfect... just what I needed...

[dsphotog]

I have a 10' long 18x22 Brown process camera that was given to me by a local newspaper.
It came with an electric Packard shutter.
For a portable variant, I think an air operated Packard would be great.
Keep us posted on your progress.
Happy shooting!
David Silva
Modesto, Ca

[philosomatographer]

ok I spent 6 hours on Sat taking apart a process camera... now I have 4 foot bellows, a negative plate and ground glass at least 30"x30" and two lenses 160mm and 205mm.

I have sketched out a three wheel base system, but I need the math for where and how big to make stuff... and good camera math resources on the web?

Shutter is also going to be an issue... I am thinking of build a couple sized film backs... one being able to hold a X of 120 to test this thing...

Ap is controlled on the lenses and they are mounted on lens boards that tension fit on the bellows....

It is going to be big, ugly and fun....

Great project, please show us what it looks like when you make some progress! One note regarding the lenses, I take it you don't actually intend on using those lenses for normal photography, do you? There is no way they will cover at infinity, unless you're going to be doing some serious ULF Macro (or process :) ) work - you're going to need some really big lenses for this thing to work at infinty.

Anybody want to start a Schneider Fine Art 550 XXL fund for icywarm?? Or (even more expensive) a box-of-sheet film fund?! :D

[icywarm]

Anybody want to start a Schneider Fine Art 550 XXL fund for icywarm?? Or (even more expensive) a box-of-sheet film fund?! :D

I am building a couple of backs for it... the first is going to hold 5 sheets of 4x5 (center, and corners)... I figure they will be easier/cheaper to work with to get the bugs out...

I have been looking at the cost of negs... looks like I will need about $450 for a box of negs and paper... plus chemical... working out the details of processing in a tub will be fun too...

I figure/hope I can get a working image at least 16x20...

I will post as I build...

[BarryS]

I suggest you build a 14" x 17" back so you can shoot x-ray film--which is very inexpensive.

[Rick A]

I started a project like this a couple of years ago, then abandoned it(lack of time). In a moment of weakness, I sold the bellows and a Goerz lens. If anyone is interested, you can have the 18"x24" groundglass and any other parts I have laying in my basement. I have the vacuum back and pump, hose, and a killer light source as well, all 18x24. All you have to do is come and pick it up or pay shipping.

[ic-racer]

You have an 18x24 light source? How many watts? I know someone that may be interested.

[Process Camera Guy]

ok I spent 6 hours on Sat taking apart a process camera... now I have 4 foot bellows, a negative plate and ground glass at least 30"x30" and two lenses 160mm and 205mm.

I have sketched out a three wheel base system, but I need the math for where and how big to make stuff... and good camera math resources on the web?

Shutter is also going to be an issue... I am thinking of build a couple sized film backs... one being able to hold a X of 120 to test this thing...

Ap is controlled on the lenses and they are mounted on lens boards that tension fit on the bellows....

It is going to be big, ugly and fun....



The math for calcualting lens and copy position for a given enlargement or reduction is as follows:

Film to lens = M (magnification) + 1 X the focal length

Film to copy = [(M +1 / M) + ( M+1)} X the focal length

Example 100% same size , with 19" 480mm lens
M = 1

Film to lens = 1+1 X 19" = 38"

Film to copy = ( 1+1 / 1) + 1+1 X 19"
4 X 19" = 76"

Example 2 - 300%, 3X, 610mm 24" lens
M = 3

Film to lens = 3 +1 X 24 = 96"

Film to copy = [( 3+1/ 3) + 4 ] X 24" = 127.99"

Now you know why process cameras are so big.

Now the you know the distance, use the lens angle of coverage (actually half of that) and use these distances for the long side of your right angle triangle for the trig necessary to calculate the lens coverage at a given percentage. Remember to double the result since you used 1/2 angle. Sorry no triq lesson today.

[C. D. Keth]

You know this is almost 2 years old, right?

[Andrew Plume]

You know this is almost 2 years old, right?

y'know Chris, people can get held up........................projects do get put on hold

andrew

[Leonard Robertson]

Quite a few years ago I bought a huge Roberson process camera in order to get the two lenses included - a 19" Artar and a 30" RD Artar. Camera and lenses all for $200. How could I pass it up? The only catch was, I had to take the camera, lights, vacuum pump, timer, etc. in order to get the lenses. The whole works weighed close to 2000 lbs. I borrowed a flat bed trailer to haul it, and got it home eventually. It was the lenses I really wanted, but also had vague ideas of using the camera to enlarge shorter Cirkut negatives. But I didn't really have room to set it up, so abandoned that thought. I did use the motor from the vacuum pump on a small milling machine. And the price of scrap has increased over the years to where I'll probably get my original $200 back when I haul the remains of the bed and frames for scrap.

Len

[Mark Sawyer]

And somewhere, in some garage or back-yard shed, sits yet another unfinished process-to-view-camera conversion project...