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Question for the Experts - Tonal Reproduction


William Loekken

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Do you know of any diagrams or text on the tonal reproduction of a traditional film pipeline?

I'm trying to figure out how camera stops translate onto the screen in the final projection of a 'by the book process'.
E.g. 5207 shot at normal exposure, processed normally, contact printed to 2383 and projected on a standard cinema screen.

Kodak publish how camera stops translate onto the negative - I'm looking for something similar just for the final image
914374738_52077207250D.thumb.png.4fc11925a4bd98fbb75bd81b5baadaeb.png
If there is no diagram out there already. Is there a way to calculate this?
Or another way to previsualize how camera stops will fall in exposure once projected?
- If the deepest blacks occur at -5 stops or at -2.5 - does middle gray fall at the equivalent to the-digital-512-in-10bit-viewing in the projected image? and how bright is +4 stops compared to +8

I found the Jones Diagram through the ASC article 'The Color Space Conundrum' - which has a diagram of the print-through curve. 
- How does this print-through curve compare to what's seen on screen? I tried mapping the -8 through +8 onto this print-through curve and the result looks quite flat with very soft highlights and seems to look different from the references I have and doesn't add up with the ASC manuals comment on blacks falling somewhere between -2/-3 and whites go white and lose definition around +4/+5

I hope someone can help with some answers! or even better examples

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I'm not familiar with printing (never had to do it professionally), but I would imagine that negative stock has more dynamic range than positive stock. That's probably why your mapping looks flat. My reasoning: that's how digital works. A digital camera records more dynamic range than the final output (typically Rec709, Rec2020, P3, etc).

I think this may be of some help:

https://www.kodak.com/content/products-brochures/Film/Basic-Photographic-Sensitometry-Workbook.pdf

Again, anyone please stop me if I'm wrong because I don't shoot for printing on film, so I'm definitely out of my element.

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I always felt it was more like 9-stops, 4 under and 5 over... maybe 10-stops... it's odd because you can photograph an 11-step chip chart and all the steps show up in a print, and supposedly each strip is a stop, but I guess it depends on if you count black and white. Plus printed charts don't quite have the correct luminance steps.

The print only can show these fewer stops because high contrast is needed in order to get good blacks when you shine a lot of light behind the piece of film and project it onto a white screen.

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3 hours ago, William Loekken said:

You wouldn't know of anywhere I can find examples of what such exposure ramps or charts look like would you?

I think this is the droid you are looking for:

 

DSC_Labs_CGRM_ColorBar_GrayScale_Maxi_CamAlign_Chip_1233154395_535627.jpg

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