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Where to find EFS?

baachitraka

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Apr 6, 2011
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It is indeed very interesting read about measuring SBR with incident meter as described in BTZS. But there are few things which are unsettling for me.

If I choose APX 100 to develop with Rodinal 1+50 and compute SBR as described above, I still need to know EFS and development times. How can I find these unknowns?
 
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baachitraka

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Apr 6, 2011
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Bremen, Germany.
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I do not have any facility for testing a film, so I wonder are there any charts for

- SBR vs EFS(Effective Film Speed)

- SBR vs Development times

available for APX 100 or any slow speed with any developer.
 

Bill Burk

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Look at the Agfa Datasheets for Gamma-time curves. This information can be used to figure out SBR vs Development times.

If you develop to the manufacturer's recommended times, you should achieve near the rated speed.