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 firstname.lastname@example.org
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.