Pre-Exposing Adox CMS 20 II

[Andrew O'Neill]

For a little "speed boost", like their HR-50...


https://youtu.be/Cl1CpYVe9bA

[Peter De Smidt]

Great job on the test and video!

But as far as a pictorial strategy, I don't know....I like the no-pre-exposure image better. All of these contrast reducing methods tend to kill mid-tone separation, and mid-tone separation is usually more pictorially important than having detail everywhere. Some darker scene values go black. Well.....so? Maybe just go for good tonal separation in the pictorially most important areas.

[Andrew O'Neill]

This is probably the last video I'll make about this film... unless I can get my hands on some 120! Apparently they slitted a few pancakes at 60mm...

[John Layton]

But of course you must know that slitting a stack of pancakes (agree on the 60mm slit width) right down the middle of the stack, then pouring your syrup (preferably warmed Vermont maple!) into this slit and giving it a minute before diving in...allows the syrup to propagate nicely!

[Andrew O'Neill]

But of course you must know that slitting a stack of pancakes (agree on the 60mm slit width) right down the middle of the stack, then pouring your syrup (preferably warmed Vermont maple!) into this slit and giving it a minute before diving in...allows the syrup to propagate nicely!

:D Anything other than Canadian maple syrup would be sacrilegious!

[Sal Santamaura]

Note, ADOX has denied that its "speed boost technology" is pre-exposure, while not stating what else it might be. :)

[Andrew O'Neill]

Note, ADOX has denied that its "speed boost technology" is pre-exposure, while not stating what else it might be. :)

We know better! ;)

[Michael R]

Note, ADOX has denied that its "speed boost technology" is pre-exposure, while not stating what else it might be. :)

Maybe they are gas-hypering the film stock? It worked best on slow/fine grain films and special plates for astrophotography, that sort of thing. Or maybe they’re pre-exposing the film only to some portion of the spectrum and denying it is pre-exposure because it isn’t white light.

[John Layton]

Initially quite intriguing/tempting and a bit brain-bending...the idea of pre exposing film to specific spectra - but thinking through this it makes no sense as this only adds density because there is no modulation from specifics of subject matter and lighting on location. Make sense? Hmmm...my brain is still somewhat bent!

[Michael R]

Initially quite intriguing/tempting and a bit brain-bending...the idea of pre exposing film to specific spectra - but thinking through this it makes no sense as this only adds density because there is no modulation from specifics of subject matter and lighting on location. Make sense? Hmmm...my brain is still somewhat bent!

It was musing more than anything else. Panchromatic films don’t have the same sensitivity to all wavelengths (for example there is often a dip in the cyan area) so the speed is basically an average and depends on the white light spectrum. One could try to increase speed (slightly) by targeting spectral sensitivity dips with pre-exposure.

It could possibly be some sort of hypering - we know historically this tended to work well (relatively speaking) with slow films with extended red sensitivity (Tech Pan for example), and Adox HR-50 does happen to be an extended red film. However I don’t know how well hypered films store. I’d have to go back to the books in that one.

On the other hand, comparing the plain and speed-boosted curves for HR-50, the difference looks suspiciously like a flare factor (ie what pre/post-exposure does), which increases the threshold speed but reduces shadow contrast.

Who knows.