Finally, the Edwal Super 20 actual production formula.
First a little background with a post I put up on Photo Net in 2003. It was as follows:
Through the mid 60s to the 80s I used Edwal Super 20 exclusivly after trying virtually every developer then available, becase it gave an unequaled combination of very fine grain, high sharpness and (most of all) super compensation for the usually over-contrasty outdoor shots taken in the harsh Florida sun. I had originally become a fan of it because I had supplemented my TA stipend in graduate school by doing affordable 35mm portraiture and found it gave beautiful grain and tonality in that application.
I am ready to do whatever it takes to duplicate the formula. Bud, the owner of the Photographers Formulary has talked to Bill Troop, co-author of the Film Developing Cookbook about the formula given there on page 67 and Mr. Troop has said that it is NOT, in fact, the correct one. The Film Developing Cookbook mentions in a note regarding the formula given that "incorrect" formulas have been published elsewhere. The Photographers Formulary suggested that if I could obtain one or more of these it (in conjunction with the Troop formula) it would give me a starting point to experiment with to try to home in on a working formula.
If Super 20 can be duplicated , Bud would consider making it available to the B&W enthusiast community. I don't know how many of you have used Super 20 in the past, but rediscovering the formula would be a great service to the B&W community. It is a staining developer with many Pyro-like qualities, but with much finer grain, better acutance and much better compensating characteristics. If you can give me any leads I will be dilligent in following up and getting you the results of my attempts to replicate the formula. I have thousands of Super 20 negatives so I know exactly what results I am looking for! Thanks! Jay Ludvigh
There was a good bit of discussion and speculation at that time, but nothing definitive regarding the exact formula. After conversations with Bill Troop and a bit of detective work I was able to track down Bob Schrader who was the production line supervisor for Edwal during the last years Super 20 was in production. He agreed to give me the formula, but asked that I not disclose it because he thought he might someday want to market it. I mixed it up using the facilities of the chemistry lab at the university where I'm adjunct faculty, because it is hard to get into solution an requires a heated magnetic stirer to get the job done. I compared it to my original negatives and while there were some differences because of the changes in more modern films it was clearly the same developer. I also was able to get an unopened, well stored bottle of Super 20 and compared it to my brewed version with modern films and found the results identical. So, what we have here is the real thing.
The problem is that it is a pain to brew and I no longer have access to the chem lab due to a change in personel. I have been thinking that with the actual formula and expert input from savy APUG members, a more user friendly home brew method could be found. I have tried to contact Bob Schrader but have been unable to do so and since it has been over 9 years since he asked me to keep the formula to myself and nothing has happened in terms of him producing it I decided to make this post.
Here is the exact formula which he provided me. According to the chemist who helped me make the first batch it has "archaic" chemical terms and units of measure, but here it is:
To make 1 ltr
1) Hot water 120-130F (distilled preferred) approx 28 oz.
2) ParaAmino Phenol 2.62 gm
3) Sulfuric Acid 66 degree baume .2154ml
4) Sodium Sulfite 89.95gm
5)Para Phenylene Diamine 9.59gm
6) Glycin 4.797gm
7) Water to 1ltr
Adjust with caustic soda/28% acetic acid
do not add second chemical until first is dissolved
The above is the word for word info he sent me on how to make Super 20. I sent him a heartfelt e mail of thanks and have not heard from him since. I deeply hope he is not still out there planning to go into production himself and am only posting this now to benifit other "film dinosaurs" like myself.
If anyone with photochemistry expertiese out there can use the formula to figure out what Gradol was or how to brew Super 20 without having to use the sulfuric acid and ph adjustment process this could become a developer that a lot of people could use.