Many people talk about "fresh D-76". Mr. Sexton mentions it in his excellent article. Mr. Grant Haist spoke of D-76 and D76H in the above mentioned book. Apparently D-76 has a change in the PH after sitting for awhile and can change your processing. His D76H, which is lacking the Hydroquione, does not change in PH, and reportablely is a more stable developer. It is also very, very cheap. As a suggestion, order the appropriate chemicals from a company that sells photographic chemicals and try it. I think you will be pleased with the results.