Thanks for posting the paper Joe.Joe Farina wrote:Hi Steven,
Thanks for the update. Dye-sensitized DCG is tougher than regular DCG. Sometimes I've gotten results which were just as bright as my earlier blue-exposed DCG, only to find out that I couldn't repeat it. Adding color is tougher still. I work during the daytime, so I've also had some very long days (in your case, nights)
I've attached a paper on dye-sensitized DCG (apparently the first one by Graube in 1973) in the pdf input section. Not that it's necessarily relevant to your tests, but sometimes a paper can have a detail which makes it useful.
Interesting that two IPA baths at 50% are used, one at an elevated temperature - I must give that a try.
Another thing I noted was they suggest prehardening gelatin coated plates using Kodak rapid fixer.
I don't know much about chemistry (moles), or the dye being used, but I do have some TEA.
I have just sensitized another couple of plates with my mix.
One with bovine gelatin and one with pig skin gelatin.
What sort of swelling bath temperature do you use with your MBDCG?
In the tests that I did, I had to push it up to 30C before I had any sign of milkiness.
I wonder if my gelatin is too hard.
I did wash the plates under cold running tap water for 20 minutes or so to get all the TMG and dye out.
I know that a long soak in cold water can cause the gelatin to resist swelling, even at an elevated temperature.
Maybe I should try using the first washing water at ambient temperatures.
Steven.