Barry Thorntons Unzone system – practical question

[Jerevan]

Just a practical question for those who use this method:

As it is now, I am exposing the paper during 17,4 seconds at f11 and grade 2 ½ (white light), on Ilford MG IV. I get a barely discernable difference between the sprocket holes and the filmbase.

Regarding the contact sheet - should there be no visible difference between the sprocket holes and the filmbase, ie should everything be all black? I’ve read and re-read the paper but I am not sure how it should look.

 

[hadeer]

Wirelessly posted (Palm TX: Mozilla/4.0 (compatible; MSIE 6.0; Windows 98; PalmSource/Palm-D050; Blazer/4.3) 16;320x448)

My interpretation is that there should be a barely visible difference in density between the blank parts of the film and the sprocket holes. As an alterntive, I use a strip of paper that is a bit longer than the film strip, which leaves an uncovered part at the end. That part is a little bigger than the sprocket holes and makes it easier to judge whether there is a difference.
Anyhow, I think that consistency between contact sheets of different films is more important here than one or two density steps.
Hans.

 

[rmolson]

Barry Thorton

In read the article again I think the words the film edge by the sprocket holes might be misleading. He would be referring to the film base not the sprocket holes them selves. They are air and have no emulsion or base density. Perhaps a better choice would be to use the unexposed but developed leader for the test The human eye is a marvelous comparison device,. but it can be fooled If your maximum black is equal to the sprocket hole you have to be exposing too long.