Here are a couple more examples of the dry process for tintypes I have been working on.
I like them. Could you provide some more details on your process? Are you able to coat a plate, take it to the field to make a picture, then return to a darkroom for the chemical process?
Yes, the plates are coated and stored untill ready for use. The emulsion was home made, from Kodak AJ-12 instructions. The silver was added all at once rather than over a 10 min. time span as directed. And used Photo gelatin with the addition of
.02 % soluton of sodium thiosulfate as a sensitiser.
Exposure is about 1/2 sec @ f:16. in sun.
Development is with Dektol 1:1, Potassium Thiocyanate 1gm per oz. of developer. (Ammonium Thiocyanate can be used also but produces an ammonia odor as soon as the plate is put in the developer,it also gives the picture a more yellowish warm tone and slightly brighter.)Develop 90sec. - 2 min. I have found the 90 sec. development time better as the plate does not accuire as much fog or sediment deposit. Also, the Developer can be used full strength.
Rinse. fix, wash, dry.
I use 1/6th plates for testing so I can make up a whole bunch and burn'em up to get an idea of what they will do.
Go fourth and be positive.
What material do you use for the plates, and what thickness? Did you have to modify a film holder to accept the plates?
So, it is the Thiocyanate added to the developer that makes the developed silver light enough to look positive against the dark background of the tintype base color?
Have you tried the iron salts developer that was used for collodion tintypes?
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I used .020 thick black trophy plate coated with clear gloss poly urithane spray,dried a few days befor coating. The back of the plates also have a coat of varnish to keep from reacting with the developer.
I have been using wet and dry plate holders but a cut film holder will work as long as the plate is cut narriow enugh to fit between the guides and it will slide under the top portion of the holder while the bottom part of the holder covers over the bottom of the plate. When using a film holder it would be best to modify it a little by carving down the hinged bottem part a little so the plate won't put pressure on it but it will still work if you don't.
I have thaught about giving the iron developer a try but think that if it did work there would have been something mentioned about it in the old manuals, and I have read through pleanty of them. Tihink I'll give it a try any way.
Some thing you shuld know about this process, it makes the developer turn murkey after a few plates, but pouring it into a tall jar or bottle the solution will clear by the next day and can be used again. It seemed that it has a limit of reuse, maybe a few times?
Kevin - where do you get the trophy plate material?
I get the plate material from Main Trophy Supply Co.
They also have a toll free number, ask for Dan, He's the one I deal with but the others wil probably know what you want also. You are looking for .020 bright aluminum. If you tell them it is for tintypes he (Dan) will know what you are looking for.
I forgot to tell you that after the plate(trophy aliminum) has been used it can be washed off and recoated without having to revarnish with urethane, but to remove the varnish all you need to do is stick some tape to the edge of the plate and pull.
I am testing some plates by scuffing the surface to see if the varnish will hold more permanently.
I am still playing with collodion dry plates. These looks fun, but why do you varnish the front of the plate; the gelatin emulsion doesn't adhere?
As I recall the AJ-12 is made with Potassium salts, have you tried with Cd or NH4 salts? Seems like you might get a bit more speed with them.