General chemistry capacity question

medicineman29

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I'm sure the answer to this question is pretty straightforward, but I've been racking my brains over it for a few weeks now and just want to know definitively, the correct answer.

Reading through Ilford fact sheets and elsewhere, chemical capacity figures are given such as:

Ilford Multigrade - 50 8x10 Fibre based prints per L of working strength solution
Ilford Rapid FIx - 40 8x10 Fibre based prints per L of working strength solution
etc.

My question is this, if one were to use 2L of chemicals in a tray, does this simply double the capacity of 1L?

For example, would 2L of Rapid Fix process 80 8x10 FB prints, 2L of Multigrade process 100 8x10s etc.

or is it a bit more complicated?
 
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MattKing

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One complexity would be the definite advantages of two bath fixing.
 

Peter Schrager

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I only run 12 prints through the developer then I either replenish or start over. that way I know that my prints are getting evenly developed.
being able to repeat something is priceless
 

Doremus Scudder

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When it comes to fixer, it gets a lot more complicated. It took me some time to get my head around all the different aspects to fixation when I first started.

I suggest you read the Ilford tech sheet again and carefully, paying attention to the different capacities for "general purpose" and "optimum permanence." It's here: https://www.ilfordphoto.com/amfile/file/download/file/1833/product/711/

Short version: There are different capacities for RC and fiber-base prints. If you want optimum permanence with fiber base, your capacity is only 10 8x10-inch prints per liter of working solution if you fix with the one-bath method. With the two-bath method, you can get up to 40 8x10s per liter of first bath. If you want a lesser degree of permanence, i.e., "general purpose," then 40 8x10s per liter is the listed capacity, but these prints (after print no. 10 anyway) will not be as "archival."

Best,

Doremus
 
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medicineman29

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Thank you for the response. I already understand those points, what I'm really trying to understand is the capacity difference between a 1L & a 2L bath. You mention, for example, "If you want optimum permanence with fiber base, your capacity is only 10 8x10-inch prints per liter of working solution if you fix with the one-bath method". So taking that example, does that mean that I could produce 20 8x10's at optimum permanence in a single 2L bath? It seems logical that if you double the L you double the capacity but my hunch is that this may not be the case.
 

Doremus Scudder

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Twice the volume = twice the capacity. It's simply multiplication. 10 8x10s per liter x 2 = 20 8x10x (or equivalent) per 2 liters and so on. Your hunch is right on.

Best,

Doremus
 
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