hi i recently bought a jobo cpa-2 (same as cpe2?) and started my own c41 developing, have developed 6 rolls so far, looked good! now i am quite uncertain how to handle the chemistry to get the most rolls out of it! i poured the used chemicals (once 500ml for 4 rolls and once 250ml for 2 rolls) back to the bottle with the "fresh" solution, same with bx and stab is this going to falsify my results by the time i reach lets say 12 rolls? it somehow says 30 or 40 rolls of 35 or 120 on the package, but inside it says only 12 films per litre of solution... isn't this really just scre*ing the customer? the salesman said 30-40 rolls as well... now whats to believe? how much am i going to get out of a c41 tetenal colortec kit for 1 litre of chemicals? thanks for any information regarding this! regards from vienna!