Has anyone used Dixactol AND Pyrocat HD?

[Tom Stanworth]

Hi,

I have ordered the chemicals and scales to make my Pyorocat HD, but am itching to know what it will be like and what I should get, using Dixactol/exactol as a comparison. This will tell me if I have made up the brew right (not having mixed my own before). I have used Dixactol Ultra and Exactol Lux, but would paerticularly like to hear from someone who has used these AND Pyrocat HD to get an idea of how they differ. Like Pyrocat, Dixactol and Exactol Lux have a brown stain and I get the impression that they are similar to Pyrocat, but am only guessing.

 

[Leon]

I have used all three, Tom. I find Pyrocat HD to be like a mix of the best bits of both the Barry Thornton developers you mention. I only use 35mm and 120 so grain can be an issue for me - DiXactol was always too grainy for me. I found Exactol to be MUCH better in this respect, but the stain and accutance were not as pronounced as DiXactol. Water is very hard where I live and both Exactol and DiXactol were not overly happy with this - especially whith certain films (ie Acros for example - it was terrible - very grainy and flat tones).

Pyrocat HD gives me the finer grain, VERY sharp edges (esp with semi stand and stand methods), teh stain is very similar to DiXactol, it is very tollerant of my water supply, and I find it is much more compensating - my exposure technique can be pretty sketchy, but I havent had a prob with blown out highlights or bad shadows yet.

My methods are very non-technical and based upon my subjectivity a lot of the time, but I think it is a better all round developer.

hope that helps?

 

[sanking]

Hi,

Like Pyrocat, and Exactol Lux have a brown stain and I get the impression that they are similar to Pyrocat, but am only guessing.

There are definitely some strong family ressemblances between Barry Thornton’s developers and Pyrocat-HD. The brown stain of all of these developers comes from the fact that they all area based on pyrocatechin rather than pyrogallol, which tends to give a more greenish/yellowish stain. And all of these developers combine at least one more reducer with Pyrocatechin, which becomes superadditive with it.

My understanding of the formulas is that Dixactol is a pyrocatechin/glycol developer, and Exactol Lux contains, in addition to these two reducers phenidone as well. I notice that the working dilution recommended by Thornton for Exactol Lux is 1:1:100, same as Pyrocat-HD. I am not sure what activator is used with Exactol Lux, but for Dixactol I suspect it was sodium carbonate. There is a two-part formula by Thornton posted on the unblinkingeye.com website that I believe is a very early version of Dixactol, though based on hydroxide as the accelerator.

Thornton was a meticulous craftsman who recognized the important difference between green stained negatives (like PMK and Rollo Pyro) and brown stained negatives (Dixactol, Exactol Lux and Pyrocat-HD) when printing with VC silver papers. He talks about this in The Edge of Darkness, and even has some concrete examples illustrating the different way green stained negatives print on VC and graded papers.

Sandy

 

[fhovie]

I used DiXactol and PMK and now use PyrocatHD mostly. All are fine developers for the most part. The 2 bath configuration for DiXactol was way too compensating for many situations - perhaps a lifesaver for some. I find that PyrocatHD and Single bath DiXactol are very close in results. Perhaps Pyrocat yields a little finer grain - but for fine grain in fast-small format film, Microdol is hard to beat. I use PyrocatHD for 120 FP4, APX100 and for 4x5 TRI-X, FP4, HP5 and APX100 - and anything 8x10. I stick to high sulfate development for cute little films - especially high speed sharp grain versions like TRI-X. My issue with PMK was grain - a non issue for contact printing and most 4x5 enlarging. But PyrocatHD works well on smaller formats so why use so many developers? I only really need 3: PyrocatHD - D76 - Microdol. D76 is for IR and push processing. Microdol is for 35mm anything and 120 TRI-X. (A 16x20 print from a 6x6 TRI-X neg in Microdol is very similar in grain to a 16x20 print from TRI-X in PyrocatHD) One important thing about PyrocatHD for enlarging - DO the semi stand agitation method Sandy has posted in this NG: Divide the development into four equal spaced agitations of 5 seconds. Starting at around 20 minutes total for N development for most non-tab grain films. Film speed is much better; the low values are much more printable. I will not be using the standard - 5 sec every 30 sec agitation for PyrocatHD again for tank development of negatives for enlarging. 8x10 contact printing at 2:2:100 is a whole different story.

 

[Helen B]

"My understanding of the formulas is that Dixactol is a pyrocatechin/glycol developer"

Sandy, did you make the sort of slip that I make all the time? Glycin not glycol?

Best,
Helen

PS I think that the later DiXactol Ultra also contained phenidone. Would I be right to guess that the activator for Exactol was less alkaline than that for DiXactol - because Exactol results are less grainy and DiXactol was sharper?

 

[sanking]

"My understanding of the formulas is that Dixactol is a pyrocatechin/glycol developer"

Sandy, did you make the sort of slip that I make all the time? Glycin not glycol?

Best,
Helen

PS I think that the later DiXactol Ultra also contained phenidone. Would I be right to guess that the activator for Exactol was less alkaline than that for DiXactol - because Exactol results are less grainy and DiXactol was sharper?

Yes, that is exactly what I did. Meant to say glycin of course.

I think you are probably right about the activator for Exactol being less alkaline than for DiXactol. That could explain the finer grain. In the article he published in Photo Techniques I believe Thornton mentions that he tweaked the activator by adding a second chemical. But the degree of stain might also have something to do with the appearance of grain.

Sandy

 

[Allan]

35mm Development Times

Well it looks like the availability of Dixactol and Exactol from Barry Thornton is no more. I am hoping that Pyrocat-HD will prove to be very similar. I shoot 35mm Delta 100 and 400. Does anyone have any suggestions for development times, small tank, standard 30 sec. agitation?

 

[john_s]

Well it looks like the availability of Dixactol and Exactol from Barry Thornton is no more. I am hoping that Pyrocat-HD will prove to be very similar. I shoot 35mm Delta 100 and 400.

I'm happy with Pyrocat-HD for 120, but I wonder if an alternative to carbonate in Part_B could be investigated to minimize grain. Did I read somewhere that metaborate (or borax) with pyrocatechol are a bad combination?