Densities of Kodak C-41 control strip

Romanko

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What are the nominal densities of Kodak 12-step C-41 control strips (CAT 180 3709)? I could not find this information in publications Z-99M and Z131 Part 5. All I got is this:

Each strip has 12 steps—a yellow step, a D-max step,
and 10 equal-increment neutral-density steps. Step
indicators identify the LD and HD steps.
Kodak Publication Z-99M, page 17.

I understand that there is some variation in density between different batches and the correction factors are provided by Kodak. I would like to know the nominal density values for the twelve steps.

Also, for process control you only use five steps: Yellow, Dmax, HD, LD and Dmin. What is the purpose of the remaining seven?
 

foc

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The box of control strips has the unprocessed strips and a processed reference strip.

You read this reference strip first, on your densitometer and take note for readings.

These notes are now your reference point for the strips you process yourself and then compare their readings.
 
OP
OP

Romanko

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Sep 3, 2021
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Sydney, Australia
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I bought a partly-used roll of control strips without the reference or any documentation. I had several strips processed by a good lab and am sending them to another lab to take densitometry readings in order to establish my reference. Meanwhile, I would like to know the nominal densities. I am sure Kodak has design goals for the strips and the tolerances in exposing them and processing the reference are quite tight (though not negligible). I am also curious as to why some models of control strips have more steps than necessary for monitoring the process.
 
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