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Songyun
9-Jul-2008, 10:46
I don't have enough room for an enlarger, but I would like to make 810 contact prints. How do I make a workable light box? (I am using ilford's MC paper)

David A. Goldfarb
9-Jul-2008, 10:48
Weston used a light bulb with some tissue on it. He could adjust the height to change the exposure. If you're not doing alternative processes that require a UV source, you don't need anything more than that.

Songyun
9-Jul-2008, 10:51
Weston used a light bulb with some tissue on it. He could adjust the height to change the exposure. If you're not doing alternative processes that require a UV source, you don't need anything more than that.

How about filters for the Ilford paper?

David A. Goldfarb
9-Jul-2008, 10:54
So use a lamp with a reflector smaller than 6" in diameter for filters. If you want to get fancy, you could attach a gel holder to the reflector.

cjbroadbent
9-Jul-2008, 11:02
I.S.E., Japan make a nice simple contact printing frame. Hang a reading light from the ceiling with a fridge bulb inside, a lens cap covering the shade and with a penny-sized (US) hole in it. At 3ft. above you get a sharp point source and a 30 sec. exposure on Bergger Portrait Mat. You will need a ruby mask for white edges.

Dan Schmidt
9-Jul-2008, 12:50
I think you can get 8x10 size filters you could lay over the glass holding the negative in contact with the paper

ic-racer
9-Jul-2008, 15:17
I think you can get 8x10 size filters you could lay over the glass holding the negative in contact with the paper

Roscoe gels work great. Put them close to the light source, as any dust on them will show up to about 6" or so above the contact unless you use diffuse light.

Songyun
9-Jul-2008, 16:39
I.S.E., Japan make a nice simple contact printing frame. Hang a reading light from the ceiling with a fridge bulb inside, a lens cap covering the shade and with a penny-sized (US) hole in it. At 3ft. above you get a sharp point source and a 30 sec. exposure on Bergger Portrait Mat. You will need a ruby mask for white edges.

Chris, Do you have a link to the contact printing frame?

cjbroadbent
10-Jul-2008, 02:11
I don't have a link for the contact frame. More details though: (Multiple Contact Printer) ISE Products Co.LTD 12-16 Miniamimagome 6-Chome, OTA-KU Tokyo 143.
See photos below of this frame, the lamp, and a real contact printer by Fatif (has glass drawer for dodging tissue).

bglick
12-Jul-2008, 22:41
question: For contact prints, or even film to film contact transfers, wouldn't a collimated light source be desirable over a diffused light source? It seems a diffused light source would send rays through the exposed film in all directions towards the paper. Yet, a collimated light source would produce uniform straight rays that all enter "near" perpendicular to the film, through to the paper.

Since the film and paper are in direct contact, I realize this represents a good scenario, but it won't stop light from entering the exposed film on angles, and when passed through to the paper, it will not be as sharp as possible vs. a collimated light source. Has anyone ever experiment with this?

Payral
13-Jul-2008, 10:59
http://static.photo.net/attachments/bboard/008/0085EF-17746284.JPG

It was good enough for Edward Weston, so…

D. Bryant
13-Jul-2008, 11:47
http://static.photo.net/attachments/bboard/008/0085EF-17746284.JPG

It was good enough for Edward Weston, so…
So what are we going to use when we can't purchase incandescent bulbs any longer?

Don Bryant

Payral
13-Jul-2008, 12:16
Sun with hand coated paper - Alt. processes

CG
13-Jul-2008, 12:37
question: For contact prints, or even film to film contact transfers, wouldn't a collimated light source be desirable over a diffused light source? It seems a diffused light source would send rays through the exposed film in all directions towards the paper ...

Why don't you try it and send back a report on the relative merits?

C

reellis67
13-Jul-2008, 12:51
I was wondering the same thing. I've got a handful of bulbs for my enlarger, but I still wonder about it...

- R

cjbroadbent
13-Jul-2008, 13:01
I have tried both diffused and point source on the same negative and seen no difference. I prefer the overhead reading light to the pro contact printer because it is easier to position the negative on top of the paper rather than vice-versa.

bglick
13-Jul-2008, 13:11
> It was good enough for Edward Weston, so…

Hi Payral, I guess you are right, if Weston did it with non collimated light, then the world should stop exploring alternatives.... what a dummy I am....


> I have tried both diffused and point source on the same negative and seen no difference. I prefer the overhead reading light to the pro contact printer because it is easier to position the negative on top of the paper rather than vice-versa.

Thank you Christopher.... I think this is one of those issues that might be accurate in theory, but not in practicality. I am considering duping Provia F to Provia F, what light / method would you reccomend?

cjbroadbent
13-Jul-2008, 14:49
Point source, but watch for dust and scratches on the glass.

bglick
13-Jul-2008, 15:32
Can you be more specific...any particular point source?

Andrew O'Neill
13-Jul-2008, 15:53
I've used a piece of particle board (painted black) with pieces of wood strips (also painted black) layed on top in an "L" shape. They act as a guide for the foam rubber/negative/paper/1/4 inch glass combination. 1/4 inch glass is best as it's heavy enough to press the negative flat against the paper...fibre paper usually doesn't sit flat. Use Roscoe filters. They are quite large and very cheap. I split filter with the darkest blue and green filters.
If you have problems with newton rings because of the thick glass directly on top of the negative, switch to anti-newton ring glass (that size would be costly), or just lay a piece of mylar on top of the glass...if you still get newton rings then placing the mylar between the glass and negative should do the trick.
Oh ya, I used a frosted light bulb inside a desk lamp that I picked up from Ikea...the type that clamps to the desk and you can raise/lower.
A colleague of mine uses a a compact fluorescent bulb in a large reflector which is suspended over the negative/paper/glass combo. He says that it gives more contrast due to more UV output. No worries about it turning on and off quickly.
I now prefer to use my enlarger light source so I don't do the above anymore.

Dirk Rösler
13-Jul-2008, 22:01
I don't have a link for the contact frame. More details though: (Multiple Contact Printer) ISE Products Co.LTD 12-16 Miniamimagome 6-Chome, OTA-KU Tokyo 143.
See photos below of this frame, the lamp, and a real contact printer by Fatif (has glass drawer for dodging tissue).

http://www.ise-pro.com/e.contactprinterc.htm

I use their 10x12 free size printer, works very well.

cjbroadbent
14-Jul-2008, 06:20
Can you be more specific...any particular point source?
bglick,
see "lamp.jpg" on post #9 above. A diffused, penny sized hole in a lens cap covering a frigidaire light bulb at 3ft.

bglick
14-Jul-2008, 13:44
Thank you Christopher

Dirk, what kind of glass is on the ISE contact printer?