Paper Dev for Nova tank in tropics

[dogzbum]

I was interested in mixing some DS-14 paper dev (as per silvergrain.org) for my 20x24" Nova Slot processor. There is no Dimezone or Dimezone-S supplier in Australia and the smallest amount I can import is 25kg. Considering I would use 1g per fill (5 litre capacity) this is not economically viable.

I do not consider the Phenidone option attractive because of limited storage life and toxicity. I live in the tropics and stuff often goes bad before the expected shelf life is reached. You can carve milk that's been left out of the fridge for an hour.

My preference is for an ascorbic-based dev as I prefer to minimise residual household toxicity. I can procure most common photo chemicals and commercial products from large manufacturers (Ilford, Tetenal, Kodak, Fotospeed, etc). I prefer to homebrew as it is often more cost effective (and fun).

What can people suggest for a paper dev (preferably homebrew) for use in a Nova tank that will satisfy the following criteria:

• Minimum tank life of 2 months at tropical warmth;
• Low toxicity - probably ascorbic based;
• Neutral tone (not warm tone); and
• High volume without replenishment?

 

[Maine-iac]

[*]Minimum tank life of 2 months at tropical warmth;
[*]Low toxicity - probably ascorbic based;
[*]Neutral tone (not warm tone); and
[*]High volume without replenishment?
[/LIST]

I lived in the tropics for six years and was frustrated for three of those six. Then I discovered divided developers and lived happily ever after.

Any developer can be divided; just separate the alkaline activator from the developing agents. For a paper developer such as Dektol, for example, all the ingredients except the carbonate go into Bath A. The carbonate goes by itself into Bath B. About 20-30 seconds in Bath A, followed by about a minute in Bath B with no rinse in between will do it for you. Time is not critical, since development stops in Bath B when all the developing agents absorbed in Bath A are exhausted. It's only necessary to leave it in long enough to go to completion. It happens fast.

Other benefits: no need to control temperature. The whole time/temperature variable is eliminated. My darkroom temp in Malaysia, even with a window air conditioner was 82F, and ambient water temp was often higher.

Currently, I favor a variant of E-72 (see my article in chem recipes section) which is an ascorbic acid developer, and it can be divided easily. I no longer divide it because I'm not in the tropics any longer, but it will work just fine as a divided developer. I mix it as a concentrate (3X strength) but without the alkaline activator. When using, I dilute it 1:9 with water, then simply throw into the tray 2 Tablespoons of carbonate/liter of developer. For dividing, just put the carbonate in a separate tray.

Formula for concentrate:

Phenidone .5g
Sodium Sulfite 45 g
Ascorbic Acid (Vitamin C crystals) 19g
Edwal liquid Orthazite (benzotriazole) 10ml or Potassium Bromide 2 g

If you want to, you can eliminate the sulfite and use 6 g of Hydroquinone, turning it into a PQ developer; this might make it work better as a divided developer.

You won't need to store the concentrate in a refrigerator. It will eventually oxidize over time, but will keep fresh and active for many months. I'm 10 months into my current batch, and it's still going strong.

Larry

 

[Gerald Koch]

For ascorbate developers you need another developing agent in combination with it. For this you have only two choices Metol or one of the phenidones (Dimezone S is a substituted phenidone) whether you mix your own or buy a commercial product. Actually the phenidones are less toxic than Metol.

 

[Ryuji]

If you can't obtain Dimezone S, I suggest to use plain Phenidone instead. With Phenidone, I wouldn't mix more developer than what you'll use in 6 months.

Nova Monochrome in 20x24 size must be very nice! I do 20x24 using single tray method (takes about 1.5-2 liters each of dev and fix solution) but it's a lot of work! I can see that's still a lot of work with Nova, though.

 

[john_s]

.........High volume without replenishment?

I use a Nova and the liquid level must be maintained else the edge/top of the print will not be immersed. Significant amounts of developer will be carried over with the paper, so you will have to replenish. With fibre paper, the rate of replenishment necessary to keep the level up is quite a lot, in fact from a chemical point of view it is probably a very generous level of replenishment. Plastic coated papaer would not be nearly so thirsty.

Following our recent correspondence, I got reasonable quotes from Digital Truth and the Formulary for posting Dimezone-S to Australia. One is Indian or Chinese, and the other "sourced from England". Would there be much difference?

I suggest that you bite the bullet and get a couple of pounds of Dimezone-S from the USA. This will make a few thousand litres of paper developer which should keep you going for a while. Alternatively find a few photographers in Oz to share 25kg with me.

 

[Ryuji]

I have samples of both James Robinson and Indian Dimezone S. They are both fine granules and orange color, although the hue differs slightly. If you are making working strength DS-14 they would work the same.