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View Full Version : The importance of a wetting agent.



Jmarmck
20-Aug-2014, 14:10
Here is a n00b question but I think others might gain some benefit.
I live in an area where chemicals are none existent. The local shop has old supplies of fixers and developers but she does not have a wetting agent (Photo-Flo). The few B&W batches I have processed have been with D-76, a wash for the stop, rapid fixer, and about an hour of washing. Yes I skipped the hypoclear and wetting agent. Momma raised a bad boy. The water here is heavy with lime.

With the hour washing and no post fix chems what issues will come up? I have been reading about wetting agents from house hold items like a odorless dishwashing detergent, brand name omitted. In the soil physics laboratory we used to use a chemical called hexametaphosphate to disperse the soil particles and remove organic matter. It is a dispersant agent that used to be common in most detergents until it was found that phosphorus is responsible for most algal blooms degrading water quality. The old timers referred to hexametaphosphate as Clagon, the dishwasher detergent.

What wetting agents do you use, if any.

Mark Sampson
20-Aug-2014, 15:01
I used Photo-Flo 200 for decades (but I'm from Rochester and worked for Kodak). Now I have a tiny bottle of Edwal LFN. Two drops make a pint of working solution , which fills a 5x7 tray for finishing a batch of 4x5 sheet film. The purpose of a wetting agent is to keep water spots from leaving marks on the negatives. Calgon or similar may do the same thing; the question is finding the correct (very) dilution. Too much = soap stains, too little = water spots. I'd mix whatever you use with distilled water if as you say, your tap water has lime in it.

Mark Sawyer
20-Aug-2014, 15:03
We have a fair amount of calcium in the water here in Tucson, which makes for residual water spots. I tried Photoflo a few times long ago, and found it didn't help. Now I just give my film a quick dip or rinse in distilled water, and it comes out quite clean. No minerals in the water, no water spots left behind after it evaporates...

Peter De Smidt
20-Aug-2014, 16:43
I use distilled water with a tiny amount of Photoflo. As Mark suggested, try a couple soaks in distilled water and hang to dry. (You want the distilled water to leach out any lime.) If you don't get any water spots, then there's no need to order another chemical, albeit an inexpensive one that lasts a long time. Using hypo clear would cut down significantly on your water usage.

Doremus Scudder
20-Aug-2014, 17:12
Sheez... We live in the 21st century now. Mail order yourself a small bottle of PhotoFlo 200 and use it as directed. When you run out in a few years (or more), order another one. Drying marks are a royal PITA when printing and you don't want them.

As for hard water: use a distilled water final rinse, mixed with your PhotoFlo. Agitate the negatives in the solution for longer than the PhotoFlo directions in order to get as much ion exchange as possible. Your goal is to get as much of the minerals out of the emulsion as possible. I like three minutes with my water, but I use longer when the water is harder. You'll have to figure out how long you need to eliminate mineral deposits.

Don't reuse this solution; mix it new for each batch of three-four rolls, otherwise the minerals will build up in the bath and give you marks.

Believe me, it's a lot easier to do this than to deal with marked negatives.

Best,

Doremus

mdarnton
20-Aug-2014, 17:42
I don't have to do it, but a couple of times just to see what would happen, I tried distilled water, by itself. It's something of a miracle, actually.

Jmarmck
20-Aug-2014, 19:30
Some good information. Thanks. I have a septic thank and am concerned about dosing it to the point of upsetting the balance. I try NOT to send any chems down the drain. The distilled water sounds like the way to go.

neil poulsen
20-Aug-2014, 19:39
You can also check with the company that makes your developer.

For example, for a period of time, I was using Ilford's ID11 and was told by an Ilford technician that ID11 has it's own wetting agent. He said that, given the effectiveness of the wetting agent, it was unnecessary to pre-soak the engative in water.

Peter De Smidt
20-Aug-2014, 21:23
Using a drop of photoflow in your final rinse uses way less soap, photoflow is similar to soap, than does washing your hands. Your biggest environmental impact with your current procedure is the amount of water you use to wash your film.