Discussion in 'Alternative Processes' started by kevin klein, Feb 19, 2007.
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?
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.
The varnish is used to hold the emulsion or it will peel right off the plate when drying. I made a simpler emulsion using the unwashed kind with only po.brom. but found it has to be washed to adheer to plates, it is actualy faster than AJ-12 and makes much better negatives,I think that will be my standard for neg use,and it is really easy to make. I do'nt add silver a little at a time as the instructions say but all at once.
This emulsion has had some problems for tintypes but I think the plates may have been contaminated or something,I did get a few positives from it with instantanious exposures.
For now the AJ-12 wil be used for positives, D-19 developer makes for a better comtrast but the plates have to be devloped for 3 minutes rather than 90sec.as with dektol.
I shot some 5x7's today and most were a little over exposed.
When making dry-plate negs, what are you coating them onto? I assume glass...
Yes, Glass is the only thing I use for negatives, so far subbing has not been needed.
Have you ever tried a pyro-based developer, like Pyrocat HD, or PPPD?
Interesting thread, a couple of things I'm curious about:
1. Why didn't you opt for say... Liquid Light (or the Agxx flavor)? Seems Liquid Light would help with contrast (VC Flavor) and be simpler.
2. Why coat with varnish instead of using somekind of gelatin base?
The reasons for not using a premade emulsion, at least for me, is cost. I did not usualy use all of a whole 8 oz of emulsion in a year so making my own on a smaller scale was much less wasetfull. Also the cost, I do a lot of experimenting and there is no point in desroying something that is priced more than what you can make yourself, besides,the Liquid light is too thick for my liking and I prefer to do my own concocting and equipment building.
The varnish is used so the emulsion will hold to the trophy plate, without it the emulsion will simply peel right off during drying. I tryed the gelatin subbing, but of course that is the same thing the emulsion is made with too,and will not stick.
Have you tried the iron developer idea in the past year since this post was active? I'm curious to know if it worked.
Thanks for the recipes and details; very useful. Please update us (or just me!) on what you've learned. I'm trying to make dry-plates work well, also, since I am not excited about the toxicity of wet-plates. But making a dry-plate look as crispy and lovely as a wet-plate is tricky.... There must be a way.
Iron developer does not work. The only thing that makes the positive image on these plates is the Ammoniumthyocyanate. Unfortunatly, I have discovered that these plates only work if the humidity is very low and the temperature is not over 70 deg.f or else the emulsion will self destruct in the developer due to the its thinness and the thyocyonate.
If you are making or want to make an emulsion for negatives, I have instructions for a formula that I made and works quite well.
Thanks, Kevin. Is there somewhere online I can view your work?
Of all the things you've tried, what's produced that best contrast?
I'm trying my own developer later this week (dektol + ammonium thiocyanate) with both Ag+ and the Rollei emulsion. I'm also going to experiment with toners, to see if I can brighten the 'white' of the image, even though I'm told it won't work. (You never know...)
Thanks for your help.
I think you will have good luck with the ready made emulsion,that is something I have wanted to try myself.
You can also use Kodak D-19 full strength for the developer as well as Ilfor paper developerdiluted 1 part dev to 4 parts water. using the same 1gm cyonate to the fluid ounce of developer. The D-19 has given a little better contrast and takes 3 minuets for development, the others take about one and a half minutes.
You can see some of my work at kevinklein.biz it is mostly collodion.
Have fun with your project.
Toner will darken the image.
Thanks, Kevin. By the way, since you offered, please do share your emulsion formula. I'd like to have that on file.
And one more question: regarding varnish. I have the formula for making alcohol/lavender/gum sandarac varnish, but if there is a commercially available varnish that will do the same thing that I can buy at Lowe's, please fill me in.
I have seen a posting on the collodion.com site that someone is using a material called Clearshield. If you want to read someones experience with it go to collodion.com and go to the forums then to "purley experimental" section and click on "modern varnish". You will have to register to log on if you have not already.
It is a water based clear UV protective coating used to protect printouts and documents, used inplace of laminating. They have a web site, clearstarcorp.com. In the past I have used shelac but it dries a little rough and dull. Give me a mailing address so I can send you emulsion instructions.
Well, today I tested a number of things, including the Dektol+ammonium thiosulfate (Dektol 1:1, mixed 3 oz to 1 gm of AmmThio; used on both Ag+ and Rollei's RBM2 emulsions) developer. In a direct comparison with the Rockland developer, the Rockland was better hands down. Sad but true. On the Rollei RBM2, the Dektol mixture left the dark areas quite foggy, and really did a number on any flaw in the emulsion, including fogging the area around any bubbles. On the Ag+, it only gave a faint image. When diluted to a 6oz:1gm solution, I got only a faint image on the Rollei emulsion.
Thoughts, anyone? I'd still rather be making my own simple developer than buying Rockland's. Any chemists out there that can look at Rockland's MSDS sheets online and help me formulate a homemade version?
On the plus side, the Rockland reversal developer combined with the Rollei emulsion resulted in better contrast and some pleasing colors (when the developer was fresh), better than the Rockland Ag+ emulsion.
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