View Full Version : Exposure time for Ilford RC pearl used as a paper negative

19-Aug-2017, 13:37
So I've had my field camera for a couple of weeks now. Love it. I'm limited to what I can take photos of because I don't have a tripod yet so I've been mainly doing still life indoors. Since it's a half plate ive been shooting paper negatives and I'm having some issues. It's taking a very long time to get a half decent negative. Is ten minutes indoors with lamp light and the aperture on f10 unreasonable? Even then the scan turns out light. Outside in bright light at the smallest aperture it takes about 30 seconds to a minute.
Lens is un named with a Bausch and Lombe Unicum shutter.
Is it just a very slow lens? Am I doing something wrong? Pardon me if this has been discussed before. I've gone through some threads and haven't seen anything that would address this. If there is an existing thread please direct me to it

20-Aug-2017, 00:14
Paper is generally around iso 3, so yes, mutiple minute exposures under lamp light are perfectly plausible. You'll run into reciprocity failure of the paper as well.

22-Aug-2017, 04:27
If you have a hotshoe flashgun it may be possible to use multiple manual flashes handheld in order to add to the lamp lighting, especially as you can then move the small flash unit around to replicate a larger softbox etc.

Edit: Using pearl paper, ie. a paper having a surface texture, as a contact-negative or for scanning will most likely reduce sharpness a lot. Either glossy or matt paper would be 'smooth' and would help your final result.

22-Aug-2017, 18:58
Thank you, both for the tips. I'm going to look around for matte paper and try flash. I tried draping a white cloth behind the still life to reflect the lamp light but it wasn't enough. This is a pretty steep learning curve for me. I'm used to film. I've also seen a lot of large format photos that I'm told are on paper and they are gorgeous but the exposure times they give seem really short.

22-Aug-2017, 20:07
Hi, I too, have been playing with paper neg. I use the ilford gloss rc rated at 3. A brief flashing (2 sec. I think at f22, 10 in height on the enlarger w/#0 vc filter) prior to loading. Iso3 is going to mean long exposure times, coupled with reciprocity and bellows if needed. But it's quick to check, cheap and easy. Just have fun.

22-Aug-2017, 20:19
ok. Coming from a small film background where the longest bellows I had is on a Kodak No. 3 Special...what is reciprocity? I read it alot here, haven't come across a simple definition yet.

23-Aug-2017, 18:18
Reciprocity has to do with the ability of the material to record light. It means as you expose the material longer it records less light. It's not in a logical way either. There are technical reasons that have to do with curves but I don't really understand that part of it. Bellows extension also requires additional exposure. If you're shooting close up like 1:1 you will need to extend the bellows to focus. There is a formula for BE you can find easily. The only thing that will decrease exposure time is more light assuming you change nothing else. Have fun. It's only photography.

23-Aug-2017, 18:27
oh that makes sense. I really am having fun, even with not so great negatives piling up. I enjoy the illogic of it all.

Peter Gomena
24-Aug-2017, 09:20
I found in my f/360 pinhole camera Ilford RC Pearl requires 9 minutes of exposure in full sun. That is with a chip of "00" VC filtration behind the pinhole to cut the contrast. Hope that gives you a starting point. You can extrapolate from there to find your own starting point.