• Welcome to Photrio!
    Registration is fast and free. Join today to unlock search, see fewer ads, and access all forum features.
    Click here to sign up

Pyrocat HD tray life?

rwboyer

Member
Allowing Ads
Joined
Oct 16, 2009
Messages
522
Location
MD USA
Format
Medium Format
After like 100 years of using the same films I am in the process of calibrating a new one and I have it most of the way there. I plan on doing my last calibration development from test shots I did this weekend.

I always tray process my sheet film so in the interest in speeding this up a bit I wanted to vary my procedure a bit. I have settled on a solution to ensure my temp consistency in my new, cold, darkroom and have a question for anyone that actually knows the answer to this:

Assuming I have enough developer in the tray -

1) How long with Pyrocat 1+1+100 stay alive in a tray? 20mins? 30mins? an hour?

2) If I develop 1 sheet and then another will the activity be about the same as developing 2 sheets at the same time? Assuming I use 2x the total working solution developer.

My concern is that 15mins in the tray and one piece of film through the developer will degrade the activity to a point where my results will be meaningless - I know the answer is to mix fresh but I wanted to save a little bit of time. In reality what I described is the worst case scenario I will likely just start two different sheets at two different times that overlap.

RB
 

I am looking at 30 - 60 mins.

RB
 
If the metavisulphite is still quite active about an hour possibly more, if the developer is older then the tray life drops you can see the colour change as it oxidises, goes blue/greener.

Once oxidation goes too far the oxidised developer stains giving a higher base fog. I was testing Pyrocat HD as a re-developer for the Ilford IT-8 toner, a Bichromate/HCl bleach followed by a Pyrocatechin Re-Developer

Ian
 
Last edited by a moderator:
As one knows, Sandy King is one of the experts in the use of Pyrocat. Hopefully Sandy will chime in. However, if one mixes the Pyrocat components in advance, such two stock components will keep for a very lengthy time in brown glass bottles stored at reasonable temperatures. To mix up a fresh batch of developer is very quick and easy from the components-really just about a minute ( if not less ) to mix a new tray of developer. Thus, never any worries about exhaustion of developer. Would such an approach work for you?
 

Well yea - I think I qualified that in my question or subsequent clarification to avoid 300,000 responses telling me to do the same thing I am already doing. I really just want to know if anyone else uses the same tray for 30mins or so with different film start times and what the effects of dev activity are?

RB
 
Since it's so easy to mix and so inexpensive, who cares?
 
Well,

obviously I care - if you want a justification it is because while it is cheap my time is not. I have 8 sheets to develop this weekend at different times for each to finish calibration of a film. If anyone has any data about this I would like NOT to have to go through 8 completely different development sessions.

A long time ago I used to process N-/N/N+ films at the same time - I need to do something similar to speed this up but... I have not done this with Pyrocat HD and it requires the developer to maintain consistent activity over a thirty minute range so that my calibration does not get thrown out of whack by developer exhaustion.

Good enough for you?

RB
 
I would develop no more than 4 8x10 sheets / liter. You're more likely to exhaust the developer by trying to develop too many sheets in a batch than you are by taking too much time. I do semi-stand development with Pyrocat HD up to 1 hour and it's fine.

I'd develop your film in two 4 sheet batches of 1 liter each. Depending on the film your optimum time should be between 9 and 13 minutes so you won't even be close to fully oxidizing either batch.

In short, the answer to your question 2) in the original post is Yes, even if you don't double the quantity of working solution unless you're doing minimal agitation development.
 

If you have a good amount of developer in the tray the working solution should last from 60-90 minutes with intermittent agitation. If you shuffle the film around constantly stay on the safe side with 45-60 minutes.

Sandy King
 
Thanks everyone - I appreciate the help - I will not worry about the time my time will be 30mins or less.

One more question for Sandy - What about the activity after developing the first sheet/second sheet/third sheet assuming I have enough developer say 1 liter - at what point will the activity change?

RB
 

RB,

The activity of the developer may decrease very, very slightly for the second sheet, and very slightly for a third and fourth sheet. However, for all practical purposes I doubt you would notice the difference holding comparison negatives side by side.

When developing 5X7 film with minimal agitation, where I use two gallons of working solution for six sheets of film at a time, I have developed up to four sets of film in the two gallons over a period of two hours. The contrast of the fourth set was just slightly less than that of the first set.

Sandy
 
With 500ml in the tray I play very safe and develop 1 sheet, then use a new batch for the next. It does take quite a while to get through my usual 6 - 8 sheet shoot, but--and I can't remember the details--I did once push my luck too far and exhausted the activity of the Pyrocat. I find it easier to stand around in a dark room listening to music than to haul the 5x7 back to the location to reshoot the failed development.

Regards - Ross
 

I think that needs qualifying a little because it's entirely dependent on the volume of developer used and the dilution along with the area of film that's already been developed. In many respects Pyrocat is similar to Rodinal (& sumilar) where a minimum amount of developing agent is needed per 35mm/120 film (10x8 sheet etc) regardless of the dilution.

So is you use 250ml for one sheet of 10x8 then it's going to be to exhausted to safely process another, but if you use a litre then it's very different.

Ian
 
When I did tray developing with a brush, I used 500ml at either 1:1:100 or 2:2:100 (depending on printing paper) for two sheets, one after the other. I'd develop, water stop and fix the first sheet, then develop the second. The process took 45-minutes to an hour.

As others have said, be sure to use enough developer, then it should last in a tray about an hour or so.
juan
 
Ian is correct in that how many sheets of film of a given size one can develop is dependent not only on the stability of the working solution with time but also on total volume. While 250ml of developer may be enough for rotary processing one 8X10 sheet of film to be on the safe side I would double that amount per sheet for tray processing if more one sheet is to be developed. More solution will also slow down the oxidation process and minimize B+F stain.

As noted earlier, when I develop 5X7 film with minimal agitation procedures I use a 1.5:1:200 dilution and develop a set of six sheets at a time in three gallons of developer. (Sorry,my earlier post said two gallons in error This amount is good for up to 24 sheets of fillm developed six at a time over a period of less than two hours.

Sandy King

 

I agree - I am just looking to save some time for the 8 sheets of bullshit calibration work that I have to do this weekend for my new "cheap' sheet film. I don't mind too much when it is photographs I care about but this is just test subjects so nail this film. Even though I decided NOT to use it for an upcoming project I am doing with 8x10 I still have a box of 50 sheets of this stuff that I am not going to throw away. I will use it for other things as the mood strikes.

RB

Ps. I find that I have to choose between listening to music and drinking while spending long periods in the dark - If I do both I get confused and I usually choose drinking - seems to make the time go by quicker ;-)
 
You must log in or register to reply here.
Menu
Log in
Register