Formula for PC-TEA developer?
Could someone give me a hint where I can find the formula for PC-TEA? I searched in this forum, but found only glowing reports, but no formula. The article on unblinkingeye.com doesn't say anything about TEA.
The formula is 9 g of ascorbic acid + 0.25 g of phenidone in TEA to make a total of 100ml of stock solution, which you then dilute either 1:50 or 1:100 for use. I also add about 0.2 g of potassium bromide to reduce fog.
Originally Posted by email@example.com
You mix this by heating the TEA to about 250 degrees F, adding the ascorbic acid and bromide and stir until it is completely dissolved, which can take quite a long while. By the time the ascorbic acid has dissolved the temperature of the solution should have dropped to below 150 degrees F, then add the phenidone and stir again until dissolved.
The normal working solution is 1:50 to 1:75.
Mr. Gainer was kind enough to send me this:
100 ml triethanolamine (TEA)
9 g ascorbic or erythorbic acid (AKA isoascorbic acid)
0.2 g phenidone
Heat to 200 F til dissolved. TEA will darken.
dilute 1+50 with water and develop HP5+ 8 or 9 minutes at 70 F. I do not have complete development charts.
For heating use a Pyrex container and put in oven at 200 F. This solution is awful looking but is quite resistant to aerial oxidation until water is added.
You can also use propylene glycol in place of TEA for a split stock. Then you would use 1 part glycol stock + 1 part TEA + 50 parts water. You can also substitute the B solution of PMK for TEA in the split stock method.