To me, it appears that the XTOL shot was of a textured surface whereas the PC-512 shot was of a smooth surface. Texture makes grain difficult for me to assess, but on examining small smooth areas of the XTOL neg, it appears that grain is about the same. If so, that's an exceptional accomplishment.
I think the grain is about the same
size but the edges on the grain in PC-512 Borax are harder/sharper and I expect that this is the reason that I perceive the graininess to be somewhat higher, though not massively so.
Here's a developer created by Patrick Gainer in 2009 using the same ingredients. His posting is
here.
...
Mark
Thanks Mark I have not seen this thread, and will link it from my blog. Like Jay's PG-110B, that is definitely pretty similar—as usual I guess we're walking the paths others have walked. It's Patrick's PC-Glycol that I used a bunch that started me with ascorbic acid developers. Interesting that he was working in this thread with it as a stock-type developer rather than a concentrate like PC-Glycol. In any case I offered up my work for anyone to use if they like it, so perhaps if nothing else it draws more attention to these kinds of home made developers. My motivation was that I found something that works really well for me and maybe it would be good for other people.
As with the many Metol/Sulfite/Hydroquinone/borax formulas, I think some differences in concentrations can make a noticeable difference (e.g. D-76, ADOX MQ Borax, and the many paper developers, etc).
Looking at Patrick's formula, I observe a few of things:
- He's using the same 40:1 developing agent ratio as PC-Glycol because he found it to be the best combination of economical and photographically active. In my testing of two baths, I preferred the look of 24:1. Jay DeFehr was using 10:1. MyTol is 87:1.
- There are even more developing agents here than in PC-512 Borax (30g ascorbic acid, 0.75g phenidone per 5L)
- Despite more ascorbic acid and less Borax, he reports a pH higher (8.5 vs 8.3) than I measured in PC-512 Borax with my equipment.
- @Murray Kelly observed in that thread that glycol affects the buffering capability of borax, which may be pertinent. Presumably through complexing some of the borax.
- I expect somewhat higher contrast from Patrick's formula because of the higher ratio of ascorbic acid to phenidone. Someone would need to test it to know. My experience is that results are not the same with different amounts—as with MQ formulas
- Lower in the thread Patrick experimented with Glycerol and was able to dissolve quite a lot of borax. There may be a path there to a nice concentrate
There are probably an infinite number of other things we could try. If you are happy with something known to work in a concentrate with a Borax part B, PC-512 Borax is, I think, pretty good.