Rollo versus ABC+

Looks like I will have the routine of doing PMK with rollfilm and ABC with sheets. Looking around last night, I noticed ABC+ from Formulary. How is this different from Rollo? Any experiences and successes with one over the other among folks who have used both?

dgh

Rollo is formulated for processing in Jobo's and PMK is for trays and tanks for roll film and ABC+ is for sheets in trays. All 3 pyros share some similarities but are really not the same when it comes down to it. Rollo and PMK are thought of as pyro for enlarging and ABC+ is contact printing as I understand it. I could be wrong but I don't think so.

lee\c

Actually, Lee, I do use ABC for developing all of my negatives. I do enlarge my 4X5's and I have found that the results are better then any orther developer that I have used. The only caveat is that if one develops TriX prof. watch for blocking of high light densities. With Bergger it works wonderfully.

Maybe I should clarify.

I know the difference betwen ABC and PMK. Believe me..after spending a weekend with Michael Smith, I REALLY know the differences.

But Formulary markets a product called ABC+ that they describe as PMK for rotary drums, just like Bostick and Sullivan's Rollo Pyro, which is PMK for rotary drums.

My question is, does anyone know the differences between these two products? Plenty of use have used one or the other, but has anyone used both?

Sorry for causing the confusion!

dgh

ABC+ and "rollo" are the same. Harald Leban worked out the formula and called it ABC+, Formulary sells it as such, B&S sells it as "rollo".

As for suitability, PMK makes splendid negatives for contact printing in Pt/Pd when used in trays. ABC+ is a better choice for rotary: it's designed to minimise excess stain that results from rotary processing in PMK. There have been comments about PMK not producing contrasty enough negatives for a specific Azo/amidol combination: this could have to do with spectral response differences between this Azo approach and Pt/Pd since PMK produces plenty of contrast for the softest palladium formulas, provided development time is long enough.