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Grainy
05-18-2012, 01:16 PM
I've tried searching the forum and google for an answer, but haven't found it. So I try to ask here.

How much water should I add to Foma Liquid emulsion?
Do I need to heat the original container first or do I just use a plastic spoon or something to take out only the emulsion I need?
How much do I need to coat a 8x10" paper with two layers?

How to apply the emulsion I have found good information about, but not about how to mix.

Guess I at least have to spend the first kilogram of emulsion just for practice, but it would be okay to start with the right mix and work from there. I have ordered the book Gandolfi recommended, but it won't arrive until a few weeks.

Photo Engineer
05-18-2012, 01:26 PM
If you can, remove just the amount you need and melt it at about 100 - 110 F (or 35 - 40 C).

You should add a surfactant and hardening agent for best results. However, you should run a test first to see if these are needed. As for diluting, some emulsions need it and some do not. The company should supply specifications, but if they do not, you may need to use some trial and error to find out what to use.

Usually, the spread or "lay down" of a silver halide emulsion of this sort is about 5 - 15 ml per square ft. That would be about 45 - 135 ml per square meter at a rough estimate. Again, experimentation is necessary if the company does not give any data.

PE

gandolfi
05-18-2012, 02:18 PM
If you can, remove just the amount you need and melt it at about 100 - 110 F (or 35 - 40 C).

You should add a surfactant and hardening agent for best results. However, you should run a test first to see if these are needed. As for diluting, some emulsions need it and some do not. The company should supply specifications, but if they do not, you may need to use some trial and error to find out what to use.

Usually, the spread or "lay down" of a silver halide emulsion of this sort is about 5 - 15 ml per square ft. That would be about 45 - 135 ml per square meter at a rough estimate. Again, experimentation is necessary if the company does not give any data.

PE

10+ years of experience tells me this:

Don't dilute!!
There will be a small bottle with hardener in the package - I never use it!

Just apply an even layer - let it dry and do it again. IF the results are grey/spotted, you have used too little emulsion - if the image looks highly contrasty and slightly yellow - then you have used too much.

Grainy
05-18-2012, 03:12 PM
Thanks. The last text says "melt the emulsion in a water bath", but not spesific about dilution. Guess I just start with a little water to see how liquid the emulsion changes when heated to 40 degrees.

My plan is to cut a 8x10" in four pieces and coat them. Then I have one or two papers for testtrip, one for normal exposure and one with dodge/burn. If that works well I can coat several 8x10" and start printing. Bought some really heavy weight, textured cotton paper, so it will be interesting.

gandolfi
05-18-2012, 04:27 PM
Thanks. The last text says "melt the emulsion in a water bath", but not spesific about dilution. Guess I just start with a little water to see how liquid the emulsion changes when heated to 40 degrees.

My plan is to cut a 8x10" in four pieces and coat them. Then I have one or two papers for testtrip, one for normal exposure and one with dodge/burn. If that works well I can coat several 8x10" and start printing. Bought some really heavy weight, textured cotton paper, so it will be interesting.

as said: NO dilution.

and PE says you have to melt in 35-40degrees hot water. In my experience it is too low. I always melt at about 45-50degrees.(not higher!)(runnng water!). If you can the emulsion to melt at 35-40 degrees, you'll have trouble keeping it liquid..

(take a tray and fill som ehot water in it. In there you put a piece of cloth. A plastic container (used boxes for "Ferrero Rocher" works great!!) is put ober the cloth (the cloth makes it stable). Take the container with the melted emulsion in a can with hot water and place that in the tray too.. this way you have hot inviroment around the emulsion all the time while you coat..)

Grainy
05-18-2012, 05:08 PM
Ah, I diluted the first "batch" with water. But I didn't make more than a maybe 50ml and 4 10x15cm sheets. I will throw them away and try again tomorrow.

Thanks a lot for the input.

Grainy
05-18-2012, 05:23 PM
First problem I discovered with the paper was that it curled upwards in the middle after i started applying the emulsion. And I need to buy a new thermometer, it stops at 40 degrees.

Photo Engineer
05-18-2012, 06:13 PM
If this emulsion is thick at 40 deg C, then it indicates a very high percentage of gelatin. Normally, gelatin is coated between 5% and 10%. Any higher leads to difficulty melting as noted above. I'm afraid I cannot give much advice in this case as I try to stay at what I am comfortable with in terms of concentrations.

If the paper curls, you may be putting down too much emulsion at one time, you may have humid darkroom conditions or you may be using a cold press or soft textured or low weight paper. I use 100# paper, or higher, and I do not use cold pressed.

I wish you the best of luck.

PE

Grainy
05-19-2012, 01:19 PM
I used some high quality 425g/m2 watercolour paper with quite heavy texture. Guess it's cold pressed, but I do not fully understand what the text "Not (cold pressed) grain fin" means.

It was easier to coat it when I cut 15x20cm sheets instead of 10x15cm, but they still curled in the middle. They're drying now, so I will print tomorrow or monday.

After I have gotten used to coating and printing on paper I plan to coat different types of rock and wood with emulsion. What can I coat the emulsion with to make the picture more or less weather resistant? I looked at my local art shop and they sold this http://www.hahnemuehle.com/prod/en/214/611/hahnemuehle-protective-spray.html and this http://ghiant.com/i/varnish2o.jpg

dwross
05-19-2012, 01:56 PM
Grainy,

Almost all watercolor paper will curl will it gets wet. You can actually use that to your advantage. I prefer paper that has a good, strong curl. If you're seeing one long upward cup/curl down the length of the paper, you're coating correctly to the grain. If you coated the other direction (i.e., against the grain), you'd be seeing 'washboarding' -- guaranteed to produce uneven emulsion. But, if you coat with the grain, and then immediately stick something round under the curl when the paper is wet and leave it there for the whole drying time, you will never get any emulsion pooling that can leave you with too-thick spots. I use cut lengths of the pool toy things -- plastic noodles (??) I think they're called -- made of plastic foam.

d

Crimson Athens
07-02-2012, 05:24 PM
Dear Gandolfi,

I m about to buy some FOMA emulsion and would like to ask you, in your experience, which fixer would you use (for fixing coated paper)? would the Silverfix 5 ltr (powder) wkg. soln be ok? Or would I need a faster one? This is what the Silverprint website says about the Silverfix: Economical sodium thiosulphate fixer in powder form, designed as replacement for disontinued Ilfofix II. No hardening agents are included and the fixer suitable for most applications that call for a non-aggressive fixer, such as printing out paper etc. Makes 5 litres, used undiluted for film, and 1+1 for papers.
thanks !!!

Photo Engineer
07-02-2012, 06:27 PM
You should use a hardening fixer to get best results with hand coated materials.

PE

gandolfi
07-03-2012, 12:28 PM
You should use a hardening fixer to get best results with hand coated materials.

PE

the fixer mentioned is fine I think. (Don't know it first hand).
I use TETENAL VARIO fix all the time, but not always... Non hardening fix IF I want to:

1:Mess around with the emulsion after the printing.
2: Use it for bromoil prints (then it is a must to use non hardening fix.)

For normal fix I use tetenal superfix. Works fine.

PE: What do you mean by "best"?

Photo Engineer
07-03-2012, 01:18 PM
Here are some thoughts.

Some papers are sized with Aluminum based agents which act as hardeners. Therefore, it may or may not be best to use a hardening fix with them. Some emulsions contain low bloom gelatin and harden differently than high bloom gelatin. Best conditions differ for these situations.

So, as pointed out, the final use of the coating as well as the support will determine the best conditions for making up the emulsion prior to coating and during processing.

Sorry I cannot give a straighter answer than this.

PE

Crimson Athens
07-04-2012, 05:01 AM
Thanks so much for your replies. Quite helpful.
Angela

Take2
05-18-2014, 02:05 PM
I have ordered the book Gandolfi recommended, but it won't arrive until a few weeks.

Sorry to revive this thread, I know its been dead for a while. On the off chance you actually see my question, which book did Gandolfi recommend? I'm getting started with Bromoils and just ordered Fomaspeed liquid emulsion from Freestyle.

gandolfi
05-18-2014, 03:23 PM
Sorry to revive this thread, I know its been dead for a while. On the off chance you actually see my question, which book did Gandolfi recommend? I'm getting started with Bromoils and just ordered Fomaspeed liquid emulsion from Freestyle.

I saw it - even on my birthday... :)

I think we shouldn't get confused here...: I thi the book I recommended was the book "Silver Gelatin" you'll find it here: http://www.silverprint.co.uk/ProductByGroup.asp?PrGrp=163

IF you're going for Bromoil, then that is not the book (great book, but nothing much about bromoil printing..)

But you're in luck... I've made that book... a whole book on "how to" in Bromoil Printing using (FOMA) emulsion as base... you can find that one here: http://www.blurb.com/bookstore/detail/3544067

Hope this helps..

Molli
05-18-2014, 03:40 PM
It's your birthday? Here's wishing you a wonderful day and a magical year to follow! :)

Photo Engineer
05-18-2014, 03:46 PM
Happy Birthday!

As a side note, remember that there are a lot of typos in "Silver Gelatin" and not all of the emulsions have been tested. So go carefully there. The first part of the book is excellent as compared to the formulary portion.

PE

dwross
05-19-2014, 02:38 PM
I saw it - even on my birthday... :)

I think we shouldn't get confused here...: I thi the book I recommended was the book "Silver Gelatin" you'll find it here: http://www.silverprint.co.uk/ProductByGroup.asp?PrGrp=163

IF you're going for Bromoil, then that is not the book (great book, but nothing much about bromoil printing..)

But you're in luck... I've made that book... a whole book on "how to" in Bromoil Printing using (FOMA) emulsion as base... you can find that one here: http://www.blurb.com/bookstore/detail/3544067

Hope this helps..

Emil,

Congratulations on the book! It looks beautiful. (Of course, I would expect nothing less given your art :)). I'm sure it will be a valuable addition to the literature.
d