[alt-photo] Re: casein image

Mon Apr 4 13:42:55 GMT 2011

Dear Peter and Alberto,

You both are such GEMS.
Have to grade and then go to school so cannot add my 2 cents on all this. Will digest and respond when I get home. 

The notes I am using on Enos' process were from the last years of his casein experimentation, where he used the powdered form.

I wish Lucas were on the list still so he can chime in but my notes on PF6 are thus:

Lukas Werth, Casein Printing PF pp. 16-18, 22 #6

He uses 0.8g casein powder sprinkled over 10cc ammonia

Before coating he uses 30 drops casein solution in 2cc water to size the paper.

Coat is about 30-32 drops casein to pigment half a pea to 2cc 7.5-10% pot di.

He exposes his 1.8dr negs 20mn, 10mn, 5mn for each successive layer with 20w UVBL 1 inch from image.

I worked with casein all day yesterday. Found my generic gum curve is unsuitable for casein and have had to go back and revisit the curve process and thus the examples, below, are first trials, please be kind :)

I posted my first casein tricolor here:
http://christinaanderson.visualserver.com/Portfolio.cfm?nK=11961
I posted two more images for illustration on casein here:
http://christinaanderson.visualserver.com/Text_page.cfm?pID=2076

After a weekend of casein I am understanding it better, much much better, but only a BEGINNING. My reason for jumping into this with both feet is that my students are intrigued and they want to do it in lab on (gasp) this Wednesday. Trial by fire here. Nothing like teaching on the fly. But I told them they are my guinea pigs to test with me and I know nothing about the process. 

Curve is different.
Exposure is almost really only 25% of gum, for sure half gum.
Colloid behaves differently.
Development is way different than gum. "Hardy" is not the word!
Printed it on Yupo and old Kwik Print paper but layers are able to rub off with a finger. May be the pigment I am using, have not tried it with a vat pigment yet.
Look (for me) is different. No gloss. Sort of if one were to use gouache. But that is because I am not using any gum arabic in my mix, e.g. the gum arabic that comes in the watercolor pigment tubes itself, but using either powdered pigments (of which casein carries a HUGE pigment load) or pigments not using gum as a binder. I wanted to make sure not to confuse the issue with gum arabic. But perhaps with lots of layers it may gloss up. The prints I have on the web are only 3 layers.
Thus I have had to really separate it from my gum process instead of looking at it as another colloid to be used IN the gum process.
Consider all the notes, above (except Lucas') with a big grain of salt as I am sure it will change weekly, and Peter Blackburn can chime in here with his experiences using homemade (from cheese) casein which may be completely different as I am only using purchased dry or liquid casein.
Chris

Christina Z. Anderson
christinaZanderson.com

On Apr 4, 2011, at 6:14 AM, Peter Friedrichsen wrote:

> I did some experimentation with casein in the last couple of years so I can add a little to this:
> 
> First off, I duplicated Alberto's results of the percentage of casein by weight. I had read that it is 28% by weight of skim milk, (specifically cows milk ) but when I dried it down after separation I noted 23% of dried weight of skim powder which is the same value noted by Alberto. Information I gathered about the viscosity is that it varies by pH, temperature, type of caseinate salt, and of course concentration. First, the viscosity goes up rapidly with concentration; for instance, the viscosity increases almost 6 fold going from 8% to 11% of sodium caseinate. If you want to delve into this in more detail, try to find "Casein Viscosity Studies by Harper F. Zoller. I found it some time ago freely on the internet.
> 
> What I enjoy about casein is its ability to hold such a high pigment load without staining, when using such a low percentage of actual casein in the emulsion vs gums 30-40%. I always wish to load more casein into the emulsion for a stronger image but the viscosity will go off the chats above about 12 % making it un-brushable. The best for me is to work with it on the slightly acidic side where its viscosity is less than when made alkaline but not too acidic of course, because the emulsion starts to break down going below about pH 5.5, based on my tests.
> 
> Peter Friedrichsen
> 
> At 05:02 AM 04/04/2011, you wrote:
>> Christina,
>>> I was following Franklin Enos' formula,as much as I can deduce from his notes.
>> 
>> There are three identical articles from Enos/Theisen notes:
>> http://www.etheisen.com/index.php?option=com_content&task=view&id=9
>> http://glsmyth.com/AltProcess/Articles/Casein/Casein.htm
>> http://unblinkingeye.com/Articles/Casein/casein.html
>> These notes explain how to prepare casein solution by adding ammonia to powdered milk curdled with acetic acid, and not straight from ammonium caseinate.
>>> ... Lukas Werth uses an 8%, even thinner. It is difficult to deduce percent solutions from the old recipes because they would pour ammonia into milk or whatnot and then extract the whey, so who knows how much the whey weighed.
>> 
>> Lukas Werth's website www.lukaswerth.de is not online anymore, nor I have now at hand PF #6", but my notes say 0.8 g of dry casein plus 10 cc of 9.5% ammonia. This is indeed about 8% or something less, if you take into account the volume of the casein. But this is not thinner than Enos/Thiesen formula.
>> I tried to measure the yield from (my) powdered milk: it was 23% of dry casein. In addition, the apparent density of (my) powdered milk was 0.29 kg/dm3. So, to find the amount of dry pure casein used by those recipes that start from powdered milk, you have to multiply the volume (in metric units) by 0.29 and then by 0.23.
>> This said, Enos/Franklin formula uses 1/4 cup (that is 2 fl.oz = 58 cc) of powdered milk, and to the curdle you have to add 75 cc of ammonia.
>> This means 58*.29*.23= 3.87 g of dry casein = less than 5% depending on how much water is in the curdle. And how much ammonia is in the supermarket bottle? 5%? 1%? In mine  it is written "not more than 9.5%". BTW, as a matter of fact, also pure water contains not more than 9.5% of ammonia!
>>> The interesting thing is there is a difference in pH between sodium and ammonium caseinate: sodium is 6.6-7.2, ammonium 5.7-6.7.
>> 
>> It is not surprising, because at first it depends on the strength of the bases (NaOH or NH4OH) bonded to the casein. Then it depends on how much sodium hydroxide or borax has been used to dissolve the casein.
>>> Alberto, if you would like me to bring you some ammonium caseinate when I come to Italy, I can.
>> 
>> I am (was) happy with my casein+ammonia solution, but I am ever curious so I will give it a try. In return, If you wish and we will have time, I may show you how to prepare a casein solution ready for use in about 15 minutes.
>>> I traveled with some casein powder already and no questions were asked, but my friend's husband's casein/whey protein powder for drinking was confiscated so you never know. I thought since it was in a baggie they might think it was cocaine.
>> 
>> In 1990, I travelled Austrian/Switzerland/Italian borders with a fridge full of snow samples gathered for a study on Alpine pollution, and I had to declare that I was carrying "snow"... :-)
>> Alberto
>> www.grupponamias.com
>> www.alternativephotography.com/wp/photographers/rodolfo-namias-group
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