Kodak Photo-Flo 200 Dilution?

[Erik L]

Interesting. I wonder why there is a difference. According to the MSDSs, both use very similar ingredients.

I'm not sure what the secret sauce is in lfn, but it doesn't foam up and is idiot proof which is a bonus for me
regards
Erik

 

[Tim Gray]

I should add that in my previous apartment, the water was different and I used 1:200 with no problems.

 

[David Brown]

I used it at 1:200 (per the directions) for years with no problems. I then read so much about it working at bigger dilutions, that I generally go 1:400 now. Still works.

But, In all fairness, I am a big believer and proponent of following the directions.

 

[Sirius Glass]

Steve

200ml PhotoFlo to 1ml water? Wow! :confused:

[I am so embarrassed.] I would stand corrected but I am sitting in front of the computer.

1 ml PhotoFlo to 200 ml water

Steve

 

[Gerald C Koch]

I too have experienced water marks with ussing too much Photo-Flo. Only a drop or two are needed for each 250 ml. You need just enough to break the surface tension of the water. The problem seems to be with the anti-foaming agent that Kodak uses, a tallowate. As the name implies it is made from grease. The other active ingredient is Triton X-100.

 

[images39]

Ralph,

I started out using Kodak's published 1:200 recommendation, but constantly had problems with spots on the film. I use tap water (probably average hardness?).

After reading somewhere on APUG that Photo Flo sometimes works better at half the concentration, I switched to 1:400. It's worked great ever since then. No spots on the film at all anymore.

Dale

 

[jmcd]

I add about 20 drops to 1.25 liters of distilled water, and use this for many rolls, until I notice a hint of a problem. Then I add about 10 more drops. At this point, weeks have passed and I mix up a new batch.

I don't like to use much Photo-Flo, as this way I find it easier to rinse from my equipment The tank I use for soaking in this solution is dedicated to the task, and rinsed after use. I started this after I noticed some build-up in one of my developing tanks.

 

[MattKing]

I use a small drop dispenser, that gives little drops.

Some time ago I counted out how many drops there were in 10 ml of photo-flo concentrate (120). For 1:200, that would be enough to make 2 litres of working solution. I then divided that number by 10, to get the number of drops for 200 ml of working solution (12).

I mix up a batch of photo-flo working solution (usually 300 - 500 ml) and then use that same batch with every roll I develop that day. At the end of the day, I discard it.

I use tap water, and generally have no problems.

 

[Doremus Scudder]

Ralph,

I've been using Photo-Flo 200 at about half strength or a little less with great success for years now.

That said, I also use some other products successfully. I have European Kodak Photo-Flo (not 200) that is principally ethylene glycol that works well (a different ingredient than Photo-Flo 200). I've also used the Zone VI product (not sure of the ingredients, but I've still got half a liter sitting around somewhere in the States) with success. Both of these I use at half-strength or less as well.

However, I always use distilled water for the final rinse after washing.
Theoretically, if the emulsion is well-saturated with distilled water, and drops are removed from the film surface, a wetting agent shouldn't be needed at all, since there are no minerals, etc. in the water to leave deposits; and the distilled water should all evaporate away leaving nothing behind.

The danger when there is nothing to deposit on the film seems to be marks left when the emulsion dries at different rates, with lines at the interfaces around drops, etc. The wetting agent serves to prevent drops remaining on the surface of the film so it dries evenly. Therefore, it would seem to make sense that, when one is using distilled water as a final rinse and there is little or nothing in the water to cause marks by deposit, the minimum amount of wetting agent necessary to prevent drops forming would do the job just fine.

I'm not sure how the wetting agent prevents mineral deposits from forming when hard water is used for the final rinse. Perhaps it simply distributes it evenly over the film surface. With harder or more mineral-laden water, more wetting agent may be required to prevent visible deposits... It is likely that Kodak's recommendations are for a worst-case scenario, and that one can use significantly less when one uses distilled or demineralized water.

The fact that greasy anti-foaming agents, etc. are often a part of wetting agents would prompt me to use the minimum possible. Perhaps some tests are in order to see just how little will do the job now...

At any rate, it might be interesting to expand your informal poll to include water quality. How much Photo-Flo does it take to do the job with fairly hard water as opposed to demin or distilled? There is likely a significant difference.

Best,

Doremus Scudder

www.DoremusScudder.com

 

[pgomena]

I used to use 1/2 capful of photo-flo per liter of distilled water. Then the packaging changed, and the caps became enormous. I now use a few drops per liter of distilled water, just enough to make the rinse flow without foaming.

Peter Gomena

 

[Gerald C Koch]

I'm not sure how the wetting agent prevents mineral deposits from forming when hard water is used for the final rinse. Perhaps it simply distributes it evenly over the film surface. With harder or more mineral-laden water, more wetting agent may be required to prevent visible deposits... It is likely that Kodak's recommendations are for a worst-case scenario, and that one can use significantly less when one uses distilled or demineralized water.
www.DoremusScudder.com

You are right when you say that a wetting agent helps water to sheet off the film when it is hung up. Other than that it cannot directly help with hard water as these solutions do not contain any sequesting agents.

You can buy a liter of Triton X-100 from www.thechemistrystore.com for a few dollars. This is more than a lifetime supply for most photographers. Adding 75 ml of the X-100 to a liter of isopropyl rubbing alcohol will make a very useful wetting agent. The X-110 must be diluted as it dissolves only with difficulty in water.

 

[Vaughn]

We use Photoflo 2100 -- that's one part to 2100 parts water. The gallon we have is lasting a long time!

I actually make a stock solution, adding 7 or so oz (don't have the number in front of me) of the 2100 concentrate to make one gallon of stock solution. One oz of the stock solution is used to make a gallon of working solution. And I advise our lab assistants to be generous with the water -- that making it even at half-strength it will still work...but by all means never make it any stronger.

Vaughn

 

[RalphLambrecht]

... The X-110 must be diluted as it dissolves only with difficulty in water.

Gerald

Please explain.

 

[RalphLambrecht]

... I have European Kodak Photo-Flo (not 200) that is principally ethylene glycol that works well (a different ingredient than Photo-Flo 200). ...

You are right, one uses propylene glycol and the other is using ethylene glycol as it's main ingredient. Edwal LFN is using ethoxylated alcohols. This is getting confusing.

 

[hrst]

Glycol is just the solvent for the actual wetting agent (Triton X-100 in this case?). It probably doesn't make any significant difference whether it's propylene or ethylene glycol. It's just "stored" in glycol.

 

[Gerald C Koch]

Gerald

Please explain.

Triton X-100 is very thick and syrupy and requires a lot of stirring to get it into water solution. This makes it difficult to make a stock solution for further dilution to a working solution. It does mix readily with many glycols and alcohols.

The anti-foaming agent used in Photo-Flo is there mainly for use with machine processors. In the home darkroom it is not really necessary if one does not shake the working solution too much.

 

[RalphLambrecht]

Triton X-100 is very thick and syrupy and requires a lot of stirring to get it into water solution. This makes it difficult to make a stock solution for further dilution to a working solution. It does mix readily with many glycols and alcohols. ...

Gerald and hrst

In what sequence should the ingredients be mixed then?

glycol, Triton, water?

 

[Klainmeister]

This thread is confusing me. I've used photo-flo for years by simply dropping a few drops into the 120 tank + spool with running tap. Let sit for a minute or two, pull out and hang. No measurements or anything and yet to have an issue. Luck maybe?

I'm curious about the discussion of the homebrew though. Go on....

 

[Scott Wainer]

Just my 2 cents...

I use 500 ml of distilled with 5 drops of photoflo 200. The question is what am I going to do with a gallon of photoflo 600?

 

[Wade D]

1 liter of well water with 1/8 cap full (the old metal cap) of Photoflo 200 works well for me. No fancy measurements here.

 

[Mark Crabtree]

I didn't know anybody actually measured the stuff either, but water quality is certainly a factor and some might require more precision.

Too much is certainly a problem though.

 

[Gerald C Koch]

Gerald and hrst

In what sequence should the ingredients be mixed then?

glycol, Triton, water?

The Triton X-100 is first dissoved in the glycol which is then diluted with water. The recipe that I use is

Propylene glycol 250 ml
Triton X-100 75 ml
Water to make 1 l

This recipe was given in the Dignan Newsletter. The recipe also contained an anti-foaming agent which was hard to find. I therefore eliminated it since it is really not necessary for home use.

 

[semeuse]

I haven't measure in years. I just dip in a finger and swirl it into the final rinse.

 

[RalphLambrecht]

Gerald

Thanks for the clarification.

 

[ChuckP]

I also throw some alcohol in the mix. A couple caps of drugstore 91%. I read about doing this years ago and the person recommending it was a chemistry expert on some forum. I also use distilled water. Not sure if the alcohol is really needed but things look OK and it's cheap enough. If you are having problems it might be worth a try.