Shelf Life of Stock & Working Sol'ns for Gainer C? (Metol, Borax)

[al_divenuti]

Mixed my first batch of Gainer C (Metol, Sodium Ascorbate, Borax

variety) a few days back and I'm curious as to shelf life of the

Stock and Working solutions.

 

Both solutions will be stored in Brown plastic bottles. In both

cases I will not be able to evacuate all the air before sealing the

bottles.

 

FWIW, the bottles will be 1L, the temperature will be about 70-80 F

and I will be diluting the Stock solution 1:3 to form a Working

solution.

 

Thanks

[al_divenuti]

One other note - the Sodium Ascorbate is pharm. grade obtained from NOW Foods.

[sjmurray]

I don't know the answer to your question, and I'm actually wondering that myself, but I think glass bottles are probably less likely to permeate air. An easy source of 1 liter glass bottles is empty liquor bottles. Drink them yourself or get from a bar or friends. Many brands come with plastic caps instead of the aluminum caps.

 

I've been making up small quantities mixing just the buffer (borax, sodium carbonate, sodium sulfite, etc.) and adding the vit.c and 1% phenidone at time of use. Phenidone A seems to have a problem with going bad in solution more so than Metol.

 

Metol has to be dissolved first, so you have to make up the entire stock all at once. Good question.

[jay_de_fehr]

I've been making stock solutions of Gainer's metol version in a 1 quart beer bottle, and the stock solution will last weeks. I don't know if it will last longer because I always use it up in a week or two. I can't comment on working solutions because I use them one shot. As soon as my chemical order arrives I'll be switching to Propylene Glycol and TEA stock solutions which have very long shelf lives. How do you like the developer? What film are you developing in it?

[nicholas_t.]

The esablished working solution is straight and it this developer doesn't seem to work consistantly with more dilution (like D76 not D76 1:1). I'm not sure what you mean by 1:3, but if you are diluting more than the standard dilution you <i>might</i> have problems.<p>

...and yes the solution will last for some time if you have used distilled water. The problem arises if there is some residual iron in your tap water. This is <u>bad</u> for you ascorbate if you do.<p>

Other than that, good stuff. I really like this developer and in recent times it has taken a back seat to the newer, fancier, developers but it is really good. As you probably know Metol does not dissolve into Propylene Glycol...

[jordan_w.]

I now use the propylene glycol version, but used to store the developer (vit C/phenidone version) as two separate stock solutions: one containing the vitamin C and phenidone, the other containing the borax and sodium hydroxide. Both were made up with distilled water. Even in filled bottles, the vitamin C stock would gradually turn yellow over time. The activity wasn't affected too much when the colour was still pale -- after it got stronger I decided not to chance it and made up a new batch.

[jay_de_fehr]

Nicholas, the stock solution is made up according to Patrick's article here:

 

http://unblinkingeye.com/Articles/VitC/vitc.html

 

It's called "stock A" and "stock B" on the two right hand columns of the chart, and below the bottom chart are instructions to dilute 1:3 for film or 1:1 for paper.

[nicholas_t.]

Right, right... I see now.<p>

Most people now use those solutions split stock. As in, developing agents in one bottle and activator/alkaline solutions in another. This improves longevity somewhat.

[jay_de_fehr]

That makes sense. If I make up any more of that stuff, that's what I'll do.

[al_divenuti]

Jay,

 

I'm using Tri-X rated at EI 400.

 

I don't have a judgement on the developer / film combo yet. Honestly, I botched my first roll by mixing a stock solution that was diluted to working solution (which is why I'm asking about the life of the working solution in the first place).

 

I'm going to look at my 2nd roll of negs under the loupe & light table tonight and try to compare vs. my FG7 and D-76 negs.

 

I think my biggest issue is trying to get accurate sub-gram measurements (for the Metol) with my present crappy balance. So my results may not be fully representative.

[al_divenuti]

Nick, I've used good 'ol Deer Park distilled water throughout - including mixing the 10% lye solution.

[jay_de_fehr]

I don't have a balance, and just use the teaspoon measurements. So far, so good.

[al_divenuti]

Jay,

 

Having done just a 5 minute inspection of my 400TX negs with a 7X loupe and lightable I didn't see any advantage in terms of grain vs. my FG7 w/ 9% Sodium Sulfite negs. In fact, I found them to be grainier than my D-76 1:1 negs (produced with an entirely different setup and I'll be posting a topic on <i>that</i> shortly).

 

I couldn't make any real assessment where gradation or accutance was concerned. I was shooting near dusk at shutter speeds that were a challenge for hand holding and the overall SBR was pretty narrow.

[jay_de_fehr]

I get grain, too. I have no way to measure objectively the difference in grain compared to D-76 or Xtol, or any other developer, other than my grain focusing scope. The films I've been using lately are inherently grainy, so I've been seeing definite grain in my scope, but I shoot MF and LF, so it doesn't show up on my prints. SUbjectively I'd rank Gainer's developer as I've prepared it, to produce more grain than Xtol, and on a par with D-76 1:1. My prints look great. Really sharp, and smooth, and no grain at 8x10 from 6x7 negatives, even with Fortepan 400, which I'm really beginning to like. I'll post some scans when I have time.

[patrick_gainer]

I have been experimenting lately with increased ratio of ascorbic acid to metol or phenidone. The idea is this: a given amount of, say, metol will activates a certain amount of ascorbic acid. Adding more ascorbic acid than that has no practical effect on activity, but does affect capacity and longevity. Aerial oxidation will change a certain amount of ascorbate into dehydroascorbic acid, which is not a developer. Although the result can be a reduction of pH, a buffering alkali will minimize that effect.

 

You might try doubling the amount of ascorbic acid in the A part of a split stock. Make the ratio of ascorbic acid to phenidone 80:1 or of ascorbic acid to metol 20:1. You will need to adjust the amount of alkali in B to make up for the increased acicity of A, but the result should be a longer useful life of the A solution.