I made mark's 1880 dry plate emulsion found here, poured it on glass (3.25x4.25), exposed it and developed it.
Good News: no fog and it works
Bad News: SLOW. in direct sunlight @f8 30seconds gave me a thin negative.
I think I might have under ripened.
I developed in 5x7 inch trays PMK (40 drops a + 80 drops b +200ml's wate for 20 mins at 58*f. I don't have anything to measure out single ml's, so based off of this I used 20 drops = 1ml.
Stop was 2 mins in water with 2 exchanges during that time
Fixer was 25g of sodium thiosulfate to 200ml's of water.
I am so relieved that I got anything at all on the glass. Everything is swell, except for the speed of the film. I didn't have any problem with the emulsion coming off, in fact it gave me such a hard time cleaning it off of everything it touched! The only real issue is the speed which i feel is due to under ripening.
Does anyone have any tips for pouring the emulsion? I made a huge mess and left uncovered spots on the glass
Heh, I'd be interested to hear some answers to the messy situation too - I tried something similar once but the results were so abysmal I haven't bothered since. I'd love to do it again though - but yes, the mess was terrible and wasteful. There were worse issues with my results but I chalked that up to being extremely inexperienced and proceding without much understanding...
Fun times though :)
My opinion is that the development conditions are too weak for this emulsion. It should give a good contrast image with a reasonable exposure using about ISO 3 which is probably faster than what you saw.
I have one of his plates right here on the table next to me. Here is a scan of it courtesy of Mark. As you can see, it has good density and contrast.
I have posted a series of Mark, pouring this emulsion, in another thread here.
I think you have used too little developer A and B.
Wow congrats! I'll bet you'll feel a sense of satisfaction that other photographers don't feel. I remember watching a documentary on Sally Mann coating her own wet plate. Very long exposures also with the collodion process.
Do you know of any alternative dilutions for PMK? I'm using 1:2:1000 as the directions said. I have very little experience in using pyro, today being my 5th time. I think that my temp was a low for sure, but my first two plates were very, very underexposed. at 5 seconds f16 i got only the faintest lines, and 30secs at f8 appears to be at least 2 stops underexposed.
Originally Posted by Photo Engineer
The book i'm using recommends using d49 as developer.
This has been one of the most nerve racking and rewarding experiences i've ever had with photography. Thanks for your help guys :)
Most home-made emulsions have a lot of dead grains and you are coating more silver than you need. In this case, the emulsion is not sensitized with sulfur or gold so this gives even lower speed. You need a higher activity and more concentration to give better contrast, but your image above looks better than the description in the OP, it just needed a long exposure.
IDK what Mark used, I forget, and he is on a trip right now IIRC. I am supposed to have lunch with him in 1 or 2 weeks so I'll ask him for suggestions.
Myself, I use DBI under dim red safelight and D76 with no dilution. I use 10 minutes or more. Typically, if you watch the front and back, you can see the front develop much more rapidly than the back.
You say you developed for 20 minutes at 58F? If so, I suspect that's not working in your favor. I'd try to get the developer a bit warmer - at least 65F and preferably 68 or even up to 75F.
Also, PMK standard dilution is 1:2:100, not 1:2:1000.
Originally Posted by alexhill
Ah yes, I mis-typed that. I was using 1:2:100 :D
Originally Posted by Kirk Keyes
Tonight I am going to try and coat a glass that is 4x my plates size, then once its dry cut it down into four plates. That is what appears to have been done here I hope that will help compensate for my poor pouring skills. I will be scoring the glass before pouring, so i don't have to fight it later
Cutting plates after coating can be difficult due to dust and frilling of the emulsion on the edges. Best of luck.