Considering developer capacity you can only develop one roll of 120 and one roll of 135-36 with 250ml of D76. You can *fit* two rolls of 135-36 in the tank and cover them with developer but you run the risk of underdeveloping the film resulting in thin, hard to print negatives because of developer exhaustion.
One roll 120= 80 sq. in.
One roll 135-36=80 sq. in.
250ml of D76 will fully develop 80 sq. in. of film.
To do two rolls of 135-36 1:1 you will need 500ml of D76 plus 500ml of water in a 1 liter developing tank.
Quite often, Kodak's recommendations for developer capacity were based on the minimum amount of chemical needed to get a printable negative developed on an automated high volume processor.
For further information read Steve Anchell's 'The Darkroom Cookbook,' 3rd edition, for details on how much developer is required to fully develop a film.
Last edited by Fred Aspen; 06-05-2011 at 07:49 AM. Click to view previous post history.