Rollo pyro or Pyrocat HD?

[Noah B]

Hello everyone, I'm looking to use either one of these developers in my jobo 2551 tank. I've done some reading online and was wondering what everyone preferred for rotary processing? I got the book of pyro last week and it was great and I'd like to learn more about these developers specific to rotary processing. I've never used a pyro developer so any advice would be great. Thanks!

[Jim Noel]

Either one, they use different forms of pyro - Rollo uses pyrogallol, pyrocat uses pyrocatechin.
I have used both and prefer Pyrocat HD for several reason, among them is its extraordinary keeping qualities.

[Kirk Gittings]

Pyrocat has extraordinary keeping qualities in the STOCK solution. In the working solution it seems to oxidize very fast and you need to mix it up right before using. I use Pyrocat HD in Glycol in BTZS tubes with constant agitation and it works great so long as you mix it up right before using. I tried Rollo once but don't have much to say about it-not enough experience.

[Daniel Stone]

I like Pyrocat HD, especially if the intention of the negatives is to print onto Lodima. Some say that regular D-76(my "normal" developer for rollfilm negatives, 1+1) is "fine". I'm not ok with "fine". I want "tremendous". I cannot seem to get midtones to snap utilizing D-76 like my Pyrocat-HD negatives do.

Even for wet-enlarging, Pyrocat-HD has great attributes too as many here/elsewhere can attest to.

-Dan

[jonreid]

I've used Rollo for quite a few years now. I'm mainly printing my 5x7 Tri-X negs in platinum/palladium and find the negs nice for that. I've also contact printed them on silver paper and while it requires a split-grade approach it prints fine, meaning one neg for traditional and alt processes, if that interests you.

Jon

[David Aimone]

I might be mistaken, but I think Pyrocat-MC is preferred for continuous agitation over Pyrocat-HD, though they are very similar.

[photobymike]

This is from my experience of over a year....

I have been using Pyrocat HD Glycol for over a year and here are some my observations.

1. Use pipettes to measure. This stuff is so concentrated that being off a small amount effects your out come.

2. I presoak for 5 minutes at development temperature. I change out the water 2 or 3 times for the presoak. It is needed to wash away the halation barrier. This has always been important... use distilled water... the PH is slightly acid which is ok... tap water who knows what it is.....

3. Use rubber gloves when handling this substance. If you use it a lot, it can accumulate in your system and be toxic.

4. Use distilled water for mixing. I use distilled water for all of my photo chemicals anyway.

5. The negatives scan really well with my scanner V750 epson. I seem to have a longer dynamic range by at least one stop.

6. I use a Beseler roller for development... but it seems to like stand alone tank with moderate agitation...twirl the reels in my paterson tanks.....4x5 always are rolled....

7. Dilute your Stop Bath... to strong and you get pin holes. Use a stop bath to get the film ready for the acid in your fixer. Some photo guys use just water for the stop bath... but i have found that just a little acid stop works better. i use alkli fixer especially for T-grain films.. for an extra 3 minutes. I have also used Kodak rapid fixer without the hardener works well. Fix for an extra 3 minutes for a total of 8 minutes

8. When you get ready to mix your developer. Roll your bottles of concentrate before using... there seems to be some separation and precipitate on the cap after sitting for a couple of days. Do not shake but make sure concentrate is mixed.

9. Because of the tanning (hardening effect) of the developer it seems the emulsion needs more washing than normal film.... i use very strong hypo clear (Orbit) for 2 minutes each in 2 baths with vigorous agitation.

10. I take the film off the reels and soak for 30 secs in Photo-Flo. Most important; I use distilled water to mix Photo-Flo. If you use regular water or tap water you will see a sledge or slim on your finished negs... The i use a very clean sponge to wipe away the excess Photo-Flo.

I do all of this and what i end up with is beautiful chocolate colored negatives that scan really well.

Any thing to add to these observations, or maybe some questions.

Regards michael

[Andrew O'Neill]

I started off with rollo pyro and didn't like how my negatives were printing, due to their greeny colour.... I tried pyrocat-hd and love how my negatives print. It's a very versatile developer, in my opinion. It can be used for tray or tubes, at normal dilutions and highly dilute for stand/semi-stand development.


I might be mistaken, but I think Pyrocat-MC is preferred for continuous agitation over Pyrocat-HD, though they are very similar.

I never heard this before. Pyrocat-hd has worked very well for me using continuous agitation... Was the MC version designed for rotary?