devang vyas

Hi, I want to have an understanding regarding the results for a combination of DI Stocks viz Postive Stocks After recording and processing the DI Neg. is it possible to change the brand of the positive stocks. If the DI neg is calibrated at a particular DI Studio for a Brand of postive stock is it necessary to recalibrate the same Brand of DI Negative at the same studio if there is a change in the Brand of the Positive Stocks? Is it necessary to calibrate the different brands of postive stock available with the different brands of DI Negative - including cross combination . Please comment Devang