[Alt-photo] Salted Paper - Casein salt size

Keith Schreiber keith at jkschreiber.com
Sun Feb 18 18:00:41 UTC 2018


Hi David,

I think you can count on having to recalibrate your exposure time and your correction curve (assuming you are making digital negatives) for whatever method you use, every time you change any printing variable. For some processes this is more obvious than others. More so for cyanotype, less so for Pt/Pd, and my guess is salt printing will be towards the more end of the spectrum especially when toning is involved. 

My advice is to use a Stouffer 21-step 4x5 step-tablet for your experiments and testing, because this will give you more useful information than you can achieve any other way. Then narrow down your process choices and determine the relevant exposure time(s) and correction curve(s). I can almost guarantee that they will be different for each process variation. For a really good example, see Christina's recent testing of cyanotype variations. 

If you use a digital step-tablet for this you are handicapped because it is either not linearized at all, or is linearized for a different set of variables.

If you use an image negative, either analog or digital, you have no idea how close to or far from linear it is, or how a different negative would print. 

I know this approach will not appeal to some, and will seem tedious and repetitive, but in the end it will save you a lot of time and expense.

Cheers,
Keith 

Keith Schreiber
jkschreiber.com




> On Feb 18, 2018, at 10:17 AM, David Christensen via Alt-photo-process-list <alt-photo-process-list at lists.altphotolist.org> wrote:
> 
> Two questions.
> 
> I'm interesting in trying the Casein salt size mentioned in "Salted Paper Printing" but have no sodium citrate on hand - just sodium chloride.  Can sodium chloride be substituted for sodium citrate in some way in this recipe?
> 
> And - does changing salting and salt-size formulas require recalibrating my times?  I've just used the Universal salting receipe mentioned by Marek Matusz to date - so this is the first time I'm branching out with other formulas.
> 
> Many thanks for the info.
> 
> David
> 
> 
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