Help with Pyrocat MC

[rcmartins]

This weekend I decided to try Pyrocat MC mixing it from my own set of acquired chemicals. Previously I had been using R09 and Pyrocat HD bought from the photographers formulary (powder version) but wanted to try mixing my own chemicals and wanted to give MC a try. I prepared 100 ml of Pyrocat MC for part A in propylene glycol (heated to 250F) and used the previous batch of part B that I had from the PF associated with Pyrocat HD. The part A for the MC version has a much different color than the HD version, a strong brown with a slight red tint instead of a very faint brown. When mixed with distilled water at the ratio 1.5:1:250 for a semi-stand procedure lasting 36 minutes at 20ºC the developer starts perfectly transparent, water-like, but at the end of the processing has a strong brown color (that is what goes down the drain to the water treatment central). The color at the end is not the anti-halation dye since I make the film go through 2, 5 minute baths in distilled water before pouring the developer.
The reason for asking for help is that I developed a set of 5x4 Tri-X 320 sheets and while the acutance is high and the compensating effect is also higher than with the HD version, the grain is huge. I guess one can say that the grain was almost as big as with a 135 film. Doesn't seem to be normal and can only think of grain clustering for it to appear that big. Does anyone have any idea what can be wrong or where to look for? Can it be a chemical which is not good? Which one?
My catechol batch is grayish and my metol batch brown. My Ascorbic Acid is white. Can the chemicals be oxidized?
raul

[evan clarke]

Try 1.5 + 1.5 + 500 and agitate. I do it with Tri X and TMY ina rotaryrotary and it's excellent. I believe it is intended for. The brown tone after debelopment is normal..Cheers. Evan

[Ken Lee]

My Metol is tan, not brown.

Why not compare apples to apples - a sheet or two exposed and developed normally - before attempting something unusual ? The more you limit the number of variables, the easier it will be to determine any problems.

[sanking]

Mixing directions for 1000 ml of Stock A of Pyrocat-MC. Heat 100ml of glycerin to about 250F and stir in the Metol, Ascorbic Acid and Pyrocatechin until dissolved (no water or TEA required). Add Propylene Glycol to 1000ml. The end color should be light brown, or light reddish/brown and all of the chemicals should be in solution. A very deep brown would suggest that the metol powder was already oxidized to some extent. Normally the effect is to slow down the energy of the developer, but it should not cause grain clumping.

Increased grain size is usually due to over-exposure or over-development. There is no reason I am aware of that your working solution of 1.5 A + 1 B + 250 Water should have caused grain clumping. For the record, Tri-X 320 is a film that gives fairly large grain with normal development.

Sandy

[rcmartins]

Thank you for your replies, which have been helpful. Not being an English speaking native, and since adjectivation is somewhat subjective I've inserted here a photo I have taken a few minutes ago of my chemicals. The gray card beneath is a Kodak 18% Gray Card used to calibrate the white balance and as a luminance reference. Sandy, the instructions I followed were precisely those but with the exception that I divided everything by 10 so as to make 100 ml instead of 1 liter. The temperature was a bit above 250F (~121ºC) at 140ºC but I don't think that would be a problem. The colors you mention are not very far, but I am not sure. Hope the photo I've inserted helps.
Ken, naturally I do have to make an accurate comparison and that will no doubt involve an exposure index assessment for this experiment, which I have not made. However, I am not trying to make a developer comparison. I am just worried that the chemicals that I used are not proper. Unfortunately chemicals are not easy to come by and those that I have bought were bought through the "bay". If the chemicals are damaged it would be a waste of time to try to make proper tests finding the EI, agitation scheme and so on. If you think that excessive grain can be attributed to chemicals and if there is one that can be pinpointed that would be terrific.
Also, the negatives seem to have higher general stain than I get from the HD version and the shadows seem to have lower detail. These factors seem to indicate, to me at least, that I might have underexposed a bit. Now, from what I have gathered, the MC should make the films faster, not slower (I am comparing always with the HD using the exact same dilutions and agitation schemes). Again, can these factors indicate a specific chemical to be damaged? I am not a chemist so I don't really now where to look for. Thank you.
raul
114037

[sanking]

Hi Raul,

Your solutions and metol powder look fine to me.

There should not be much difference in energy between Pyrocat-HD and -MC. The main difference is that there should be less oxidation with -MC with dilute solutions and long development times.

Sandy

[rcmartins]

Hi Sandy,

Thank you very much for your insight. It has been most helpful. I will now focus on trying to get the most out of the developer/film/paper combo.
raul

[LarsAC]

Came across this accidentally - my part A of Pyrocat MC I mixed yesterday looks exactly like the above. Thanks for the confirmation.

Most difficult was to get the metol dissolved in the Glycerin. I had to stir quite some time and re-heated the solution a few times.

Otherwise it was fun and an interesting exercise. Will develop first films in the next few days.

Regards,
Lars