Pushing/Pulling questions...

[MattKing]

i never had heard the phrase

The old version of that phrase was SBR - Scene Brightness Range, but Luminance is more accurate.
You may also see Scene replaced with Subject in both phrases.

have you ever read any film manufacturers technical data info stating the films SLR number in addition to asa, iso, etc?

You will never find anything like that, because:
1) SLR relates to the scene, not the film; and
2) all films can capture extreme SLRs; and
3) the qualities of that capture, and how easy or difficult it is to retrieve the information so captured, vary with so many different variables, including exposure, levels of flare, type of developer, agitation, length of development, method of digitizing or printing, etc., etc.
If you look at the characteristic curves published by the manufacturers you can make observations about the shape and length of different parts of the curve - the toe, the straight section and the shoulder as well as the basic slope of each such part. That gives you a sense about how the film responds to high SLR subjects.
The characteristic curve of T-Max 400 has one of the longest and straightest straight sections available. It also has very usable toe and shoulder sections. For those reasons, T-Max 400 is one of the best available for capturing high SBR subjects.

 

[138S]

have you ever read any film manufacturers technical data info stating the films SLR number in addition to asa, iso, etc?

First, you may see the sensitometric curves manufacturers usually publish in the dataheets, this explains how film behaves, but you should know how to interpret those curves, read Beyond The Zone System by Phil Davis, you will practice with Logarithms.


Second, 35mm cartridges (135 format) having DX code have basic film latitude encoded, so when the camera uses Matricial metering mode the camera knows how to balance exposure in that metering mode.

https://en.wikipedia.org/wiki/DX_encoding

 

[138S]

For those reasons, T-Max 400 is one of the best available for capturing high SBR subjects.

Yes... but as highlights are not shouldered then we reach insanely high densities that may be quite difficult to print in the darkroom if we don't address that in a certain way, with scanning + Photoshop it's easier.

 

[carencrobuzzard]

thanks again, great info and well written

 

[carencrobuzzard]

hey, me again with another question, re the term and concept of SLR. for years, i have been aware, in the back of my mind, of the existence of the range of luminescence being more than the film could record. but i never had heard the phrase. so my question is, have you ever read any film manufacturers technical data info stating the films SLR number in addition to asa, iso, etc?

hey, me yet again, in my quarantine boredom i am going to try infrared film for the first time. are you knowledgeable on that? i use a gaoersi 4x5 point and shoot. thanks

 

[MattKing]

hey, me yet again, in my quarantine boredom i am going to try infrared film for the first time. are you knowledgeable on that? i use a gaoersi 4x5 point and shoot. thanks

It is best if you do searches here first and then, if you don't find what you need, start a separate thread.