New Pyrocat-M experiences?

[ongarine]

I'm finishing my Pyrocat-HD batch (propylene glycol) and I have a bunch of J&C Pro 100 8x10 to develope. All the negatives were exposed in very gray day, no sun, and subjects are old castles and fortified walls
My aim is to try Pyrocat-M with two test sheets to have the maximun of sharpness.
Before to mix the Pyrocat-M I should be gratefull if Apugers with experiences with this new Pyrocat variant have some suggestions to share.
If someone had made comparision with the "classic" Pyrocat formula would be so gently to do a pubblic test report.
It could be usefull to know the differences between HD and M.
Thanks

 

[Andy Tymon]

(there was a url link here which no longer exists)

The above link should take you to a thread about the P aminophenal version of pyrocat. I prefer this version over the hd version as it turns purple when you mix it, showing that it is active.

 

[ongarine]

No one using Pyrocat M?
Seems impossible

 

[lee]

I tested Pyrocat P and it looked and acted just like pyrocat HD

lee\c

 

[Kirk Keyes]

Maybe the metol is not sexy enough...

 

[pauldc]

Yes it is a real shame that no one as yet has seemed to have tried and tested this formula. My understanding is that this one has been designed for extra sharpness during continuous agitation methods so would be really interesting to compare the results with people (like me and many others!) using standard pyrocat-hd with semi-stand and minimal agitation methods.

I use a paterson orbital when learning to develop 10x8 film (so far having tried only Efke 100 in Rodinal) so this formula has appeal. I will try it at some point but since I still have a large (3 month) stock of homemade pyrocat-hd I won't get time for a while. Hoping in the meantime some else will be brave and give it a go and report experiences!

 

[gainer]

Yes it is a real shame that no one as yet has seemed to have tried and tested this formula. My understanding is that this one has been designed for extra sharpness during continuous agitation methods so would be really interesting to compare the results with people (like me and many others!) using standard pyrocat-hd with semi-stand and minimal agitation methods.

I use a paterson orbital when learning to develop 10x8 film (so far having tried only Efke 100 in Rodinal) so this formula has appeal. I will try it at some point but since I still have a large (3 month) stock of homemade pyrocat-hd I won't get time for a while. Hoping in the meantime some else will be brave and give it a go and report experiences!

I'm using it on 35 mm and love it, but I have no comparison to present with HD. I have used it on whatever Arista II 100 is these days, and on HP5+. If this were the only evidence, I would have to say that those who say HP5+ is grainy belong in the funny farm. I can't find the grain. Maybe it's my 79 yr old eyes, but I have some pretty good magnifiers and some sharp 11x14 prints to look at with them.

 

[resummerfield]

Where can I find the formula for Pyrocat M and P?

 

[Tom Hoskinson]

Where can I find the formula for Pyrocat M and P?

The Pyrocat formulas are here:

(there was a url link here which no longer exists)

 

[Claire Senft]

All of my experience with Pyrocat has been with metol. It was made with the substitution originally posted using 10x metol vs phenidone.

Works just fine.

 

[gainer]

All of my experience with Pyrocat has been with metol. It was made with the substitution originally posted using 10x metol vs phenidone.

Works just fine.

The most recent formula contains 2.5 g metol per liter of stock along with 50 g catechol and 10 g metabisulfite. IIRC, 10x original phenidone would be 20 g metol. Try it. You may be surprised.

 

[john_s]

The most recent formula contains 2.5 g metol per liter of stock along with 50 g catechol and 10 g metabisulfite. IIRC, 10x original phenidone would be 20 g metol. Try it. You may be surprised.

It does seem surprising if it's just as active as the old 20g metol version, as has been reported. Might part of the reason for the 20g metol version not being any more active than the 2.5g metol version be that metol has H2SO4 attached to it which might reduce the pH of the working solution (in the 20g metol version), thereby lowering developing agent activity?

 

[gainer]

Well, I have used the metol base which I described how to do some time ago in the formula section, and it is quite fine, so I doubt that the H2SO4 has any effect. I did it so I could dissolve as much metol as I might need in a TEA or glycol solution. I use an amount of TEA, MW=149.1, to balance the amount of metol, MW=344.4, plus a very little water to make a slurry which I warm to about hot coffee temperature, stir it well, then add glycol or TEA to make a solution equivalent to 10% metol. So, to make 100 ml of a 10% solution of metol in glycol, start with 10 g metol, add 8.7 g TEA (about 8 ml at room temperature) and a couple of teaspoons of water, stir and heat it, and add enough warm glycol to make 100 ml. The heat is to speed things up and can be done in a water bath or double boiler. It stays in solution after it cools. 10 ml of this solution has as much metol base as 1 gram of metol powder. It's a handy solution to have around.

 

[gainer]

I should add that I think the difference is not so much in the activity as in the more efficient tanning and staining. You'll see if you try it. Tanning improves sharpness by the optical effects. Less metol means more catechol, relatively, in the working solution. It sort of makes sense, but not in the way that makes it predictable. The proper ratio has to be found by trial and error, of which Sandy has done aplenty.

 

[gainer]

I also forgot to mention that it takes 2 moles of TEA to balance 1 mole of metol. Or is it groundhogs?

 

[ongarine]

Thanks to all Apugers sharing Pyrocat-M experiences......even if only Mr. Gainer, a true experimental wizard give it a chance in a real use.
I will mix it in the next days and then I will try it, as I said, with 8x10 sheets (J&C Pro 100) test with continuous agitation with slosher in a tray.
I will be curious what will happens and then I will make a comparision with other film between Pyrocat HD and M.
I will post as soon as my springtime laziness will disappear.......

 

[sanking]

Thanks to all Apugers sharing Pyrocat-M experiences......even if only Mr. Gainer, a true experimental wizard give it a chance in a real use.
I will mix it in the next days and then I will try it, as I said, with 8x10 sheets (J&C Pro 100) test with continuous agitation with slosher in a tray.
I will be curious what will happens and then I will make a comparision with other film between Pyrocat HD and M.
I will post as soon as my springtime laziness will disappear.......

Since introducing the two new Pyrocat variants, i.e. Pyrocat-P and Pyrocat-M, I have been extremely busy and have not had the time to do any extensive comparison testing. I hope, however, to do so in mid-July or August.

The novelty of the new Pyrocat-M formula is that it contains only 1/10 of the metol in the old version. Surprising to some I guess, but not to me since one of the first users of Pyrocat-HD substituted metol for phenidone in the same amount, got excellent results, and reported them to me.

Pat Gainer has provided me with some data that may lead to yet another formula, Pyrocat-MC, which contains pyrocatechin + metol + a tiny bit of ascorbic, and no sulfite. I like it a lot, but it must be mixed in glycol and the method of mixing metol in glycol is a bit beyond the scope of most casual users so this may be something better sold in kit form.

What I can say is that the Pyrocat-MC provides the lowest B+F and highest staining of any of the Pyrocats. I also believe that is slightly sharper than Pyrocat-HD, if the agitation is of the same type. However, this is not a new finding. If you look at my articles on Pyrocat-HD you will find that the first tests were with metol and although I later switched to phenidone for slightly higher film speed, I have always thought the formula was just every so sharper with metol.


Sandy

 

[Marc .]

Pat Gainer has provided me with some data that may lead to yet another formula, Pyrocat-MC, which contains pyrocatechin + metol + a tiny bit of ascorbic, and no sulfite. I like it a lot, but it must be mixed in glycol and the method of mixing metol in glycol is a bit beyond the scope of most casual users so this may be something better sold in kit form.

Sandy

I believe you are using metol base, as Pat Gainer described it in the recipes section, in order to dissolve it in glycol.
I hope you will still give the formula, since it will be a bit tough to find the kit over here.
Thank you for this new version of Pyrocat !

Marc

 

[gainer]

If the cat is out of the bag I guess it's OK to tell it.
You need 2.5 grams metol, 4 grams ascorbic or erythorbic acid, about 8 grams of TEA (about 7 ml at room temperature) and about a teaspoon of water to start. Mix the metol, ascorbic acid, TEA and water to make a slurry. It will warm up somewhat by the reaction, but a little more heat won't hurt. A water bath will get plenty hot. This is eventually going to make a liter, but you can start in a 1/4 liter cup. After the slutty gets a little more fluid, add some warm propylene glycol. You could also use ethylene if you are not worried about pets and kids getting into it. Now you can transfer to a larger container and add 50 grams of pyrocatechol. keep it warm and keep stirring. It will get clear and will stay in solution after it cools. The warming is more to speed up solution than to cause a reaction.

I had though there would be a precipitate of some TEA-sulfate compound, but I havent seen any. I've been using it for a couple of months with no sign of change. The activity is quite surprising, as I had always thought metol and catechol or hydroquinone had to have sulfite for synergism. I have found that metol and ascorbate do not need sulfite, so perhaps the mechanism is much like catalysis. I have read that metallic silver is a catalyst for reduction of silver halides. At any rate, the combination gives high activity, about like the HD I think, and very good tanning and staining. I think the tanning is conducive to sharpness due to the refractive effects of the proportional hardening of the gelatin. Metol, ascorbic acid and catechol are all tanners to some extent.
I didn't really want to spill the beans until Sandy mentioned it because it was his impetus and original work that built the platform. I think if you give it a try, you will find it was worth the effort.
Use it with the potassium carbonate B part about as you would Pyrocat HD for starters. 1:1:100 with semi stand development opens new doors. I have done 35 mm HP5+ and whatever the Arista II 100 is.

 

[gainer]

Fat Fingers Gaine was at it again. I hope you realized that the one time I wrote "slutty" it should have been "slurry". Not even spell checkers help that kind of mistake. Our local newspaper wrote the story of how a local logging truck went into a ditch and needed a 1 ton wench to pull it out. I have seen a few 400 pounders around, but no one tonners.

 

[Marc .]

If the cat is out of the bag I guess it's OK to tell it.
You need 2.5 grams metol, 4 grams ascorbic or erythorbic acid, about 8 grams of TEA (about 7 ml at room temperature) and about a teaspoon of water to start. Mix the metol, ascorbic acid, TEA and water to make a slurry. It will warm up somewhat by the reaction, but a little more heat won't hurt. A water bath will get plenty hot. This is eventually going to make a liter, but you can start in a 1/4 liter cup. After the slurry gets a little more fluid, add some warm propylene glycol. You could also use ethylene if you are not worried about pets and kids getting into it. Now you can transfer to a larger container and add 50 grams of pyrocatechol. keep it warm and keep stirring. It will get clear and will stay in solution after it cools. The warming is more to speed up solution than to cause a reaction.

This seems far easier than preparing the metol base first !
Thank you.

Marc

 

[sanking]

If the cat is out of the bag I guess it's OK to tell it.
You need 2.5 grams metol, 4 grams ascorbic or erythorbic acid, about 8 grams of TEA (about 7 ml at room temperature) and about a teaspoon of water to start. Mix the metol, ascorbic acid, TEA and water to make a slurry. It will warm up somewhat by the reaction, but a little more heat won't hurt. A water bath will get plenty hot. This is eventually going to make a liter, but you can start in a 1/4 liter cup. After the slutty gets a little more fluid, add some warm propylene glycol. You could also use ethylene if you are not worried about pets and kids getting into it. Now you can transfer to a larger container and add 50 grams of pyrocatechol. keep it warm and keep stirring. It will get clear and will stay in solution after it cools. The warming is more to speed up solution than to cause a reaction.

I had though there would be a precipitate of some TEA-sulfate compound, but I havent seen any. I've been using it for a couple of months with no sign of change. The activity is quite surprising, as I had always thought metol and catechol or hydroquinone had to have sulfite for synergism. I have found that metol and ascorbate do not need sulfite, so perhaps the mechanism is much like catalysis. I have read that metallic silver is a catalyst for reduction of silver halides. At any rate, the combination gives high activity, about like the HD I think, and very good tanning and staining. I think the tanning is conducive to sharpness due to the refractive effects of the proportional hardening of the gelatin. Metol, ascorbic acid and catechol are all tanners to some extent.
I didn't really want to spill the beans until Sandy mentioned it because it was his impetus and original work that built the platform. I think if you give it a try, you will find it was worth the effort.
Use it with the potassium carbonate B part about as you would Pyrocat HD for starters. 1:1:100 with semi stand development opens new doors. I have done 35 mm HP5+ and whatever the Arista II 100 is.

I am grateful to Pat for posting working directions for Pyrocat-MC. The formula is a a result of both Pat's work and ideas, and mine, so think of this as the Gainer/King Pyrocat. It is really a very nice developer, especially for folks looking for low B+F, very high stain, and very high accutance.

And best of all, it is free for the taking.

However, the mixing is a bit complicated so I will be looking to offer this formula in kit form.


Sandy

 

[User Removed]

Sandy,
Will you be offering the other two new Pyrocat formula's in liquid kit form?

Thanks,

Ryan McIntosh
www.RyanMcIntosh.net

 

[sanking]

Sandy,
Will you be offering the other two new Pyrocat formula's in liquid kit form?

Thanks,

Ryan McIntosh
www.RyanMcIntosh.net

Hi Ryan,

I would like to see that done but need to finish the comparision tests to determine exactly where to go with this. My inclination is to market the Pyrocat-MC directly. Folks have the formula but mixing the metol in glycol is a bit more complicated than mixing in water.

Sandy



Sandy

 

[Lachlan Young]

Hi Ryan,

Yes, I hope to do that soon.

Stay tuned here on APUG for further details.

Sandy

Please could you try and sort out a UK/Europe distributor so we don't have to pay the exorbitant shipping prices when we run out?

Thanks,

Lachlan