paper developer capacity

[climbabout]

Like many of you I work during the day and often print after dinner for a short session. For paper developer, I use Dr. Beers which I keep the A and B solutions in large brown jugs and mix the appropriate working solutions as I need them. The instructions always tell you to discard after the days printing session. My question is this - if you've only run 8-10 8x10's through it, is it neccesarily exhausted? I've been re-using it, if I know for instance that I will be printing again the following evening. I don't see any drop in print quality - can one of you chemistry experts chime in? How do you determine if print developer is exhausted?
Tim

 

[david b]

I've not used Beers before, although I have been told it is a great developer.

I highly doubt it will exhaust in the same day, but it probably will oxidize over the course of a couple days, especially if not covered or put into a third borwn jug.

 

[climbabout]

CLARIFICATION

To clarify - I put the mixed working solution in a brown jug between sessions.
Tim

 

[panastasia]

Tim,
It's best to judge the capacity for yourself. When development time increases in order to maintain a consistent contrast or Dmax, that's an indication of developer exhaustion. Sometimes old used developer can give you warmer print tones similar to increasing dilution with some developer/paper combinations and extended developing time.

Paul

 

[snallan]

Hi Tim, I use Beer's quite extensively, and often use a batch of working solution over several days (up to a week in a couple of cases). In between sessions I store it in glass bottles. It always has plenty of activity when I do dispose of it, but I don't fancy keeping it for another week just to use it close to exhaustion. So far I have not noticed any quantitative variation in tone for prints made using older developer.

As to determining exhaustion of the developer, I use factorial development. I watch for the image coming up, and when I see the first tone in the print I make a note of how long it took to appear. I then divide my total development time by the time it took the first tone to develop, and that gives me my development factor. Say I am developing for 120 seconds, and the first tone appears at 30 seconds, then my development factor is 120/30 = 4.

Then for each subsequent print, I measure how long it takes the first tone to appear, and multiply that by my factor to get my overall development time. Say toward the end of a session the first tone is taking 40 seconds to appear, my total development time will be 40x4 = 160 seconds. As the developer exhausts, the time for the appearance of the first tone will take longer and longer.

Personally, I have never had a batch of Beer's even approach exhaustion while printing, but generally discard it when the time it takes a first tone to appear is around 1.5 times my original (ie. in my example, when the time for the first tone goes much above 45 seconds, I would make fresh for my next printing session). I probably could use it for somewhat longer.

 

[climbabout]

Thanks

Hi Tim, I use Beer's quite extensively, and often use a batch of working solution over several days (up to a week in a couple of cases). In between sessions I store it in glass bottles. It always has plenty of activity when I do dispose of it, but I don't fancy keeping it for another week just to use it close to exhaustion. So far I have not noticed any quantitative variation in tone for prints made using older developer.

Thanks all for the replies - I often mix up a liter each of #'s 1,4 and 7 and have all three in trays for the printing session. I hate to discard it if only a few prints went through it. I usually ditch it after a week or so as well - or if it starts to give off a funny odor.
Tim

 

[Rich Ullsmith]

Tim, although I'm not familiar with the Beers useful capapcity, if you plan on printing on consecutive nights or even a few times in a week: leave the developer in the tray and cover with cellophane, with the cellophane in contact with the solution and sealed at the borders. For large trays, sectioned trash bags work well. If the enemy is oxidation, then pouring into and out of storage containers does nothing but increase the surface area (albeit temporarily) by a factor of 1000.

If I can find a densitometer, I'll post some results of a little half-baked experiment I did with dektol, after a similiar discussion here. Basically, 500ml dektol, one litre water, about 60 5X7 prints of which #1 and #60 are processed identically. This was done over a 10 day period, three sessions, with the tray covered with saran wrap inbetween. If there is a difference between #1 and #60, I can't see it. I attribute this to the avoidance of turbulence when working with oxidizing solutions.

 

[panastasia]

....... If the enemy is oxidation, then pouring into and out of storage containers does nothing but increase the surface area (albeit temporarily) by a factor of 1000.

If I can find a densitometer, I'll post some results of a little half-baked experiment I did with dektol, after a similiar discussion here. Basically, 500ml dektol, one litre water, about 60 5X7 prints of which #1 and #60 are processed identically. This was done over a 10 day period, three sessions, with the tray covered with saran wrap inbetween. If there is a difference between #1 and #60, I can't see it. I attribute this to the avoidance of turbulence when working with oxidizing solutions.

Rich,
Thanks for this info. I must agree with you on the turbulence issue, I pour the liquids very carefully, even the tap water when mixing fresh developer.

I also like the factorial method snallen talked about, I too, use a similar method to keep things under control.

Paul

 

[nworth]

Developer left in the tray spoils quickly. You might be able to get a print or two out of it the next day, but it is probably better to toss it and to start with fresh developer that acts predictably.