I've been thinking on and off about using Lith sheet film. Looking at the back archives of the alt mailing list [I think that's what it is] they talk about a low contrast developer for use with this film. The writer claims he can get a full 21 steps with Stouffer Gray Scale. Now it's available from freestyle but before I order the thing. What is it?-)) Will I be able to figure it out or should I save my $8? Obviously it's cheap enough to try it out. I get the impression it's some sort of exposure guide for the printing industry.
A Stouffer scale is a piece of film that has been exposed to different densities from clear to a solid black. To use it you will need to lay the scale over the film and expose the film thru the scale. Some how you read the scale on the film and then you are able to figure out the exposure. I would be lying if I said I knew anything else about the scale. The old time printers (offset) would use a shorter scale from Stouffer that was on a piece of paper. You would expose and develop the line film for a "solid 4". In theory, everything below 4 would be black and everything above would be white. That is all that is needed in line film processing. I would just make a test strip and be done with it.
It not for figuring out exposure but for trying to figure out the developer. At least that's what I think I might be able to use it for. I found the stouffer website and I guess I could make a few photographs of the thing. Or maybe contact the thing onto the film? Or even stick it in the enlarger? Vary the developer until I get the widest range of results on the film.
The film isn't normal so any attempt to get normal results out of it will mean some experiments with the darkroom. While I could just stick the camera out the window being able to have some sort of reference would seem to be better. But I'm not sure-)
These are "step wedges". They come in two forms - transparent and reflective. You can use them for exposure or development. They're sort of a grey card for the darkroom - they provide a known, sometimes calibrated, change in density or reflectivity. They are usually available is 1/2, 1/3 or 1/6 stop changes.
A transmission step wedge can be used to determine contrast control and EI in film development, or when calibrating a dichroic head for VC printing.
Seems odd to me, using a super-high contrast film and then trying to get 5 or 6 stops of greyscale by using different devlopers. What's the advantage of using lith film?
Partly price. Partly lack of speed. If I ever build that real big box camera then it'll be size. Partly it's just something different to try out. I don't intend to use it for anything serious. At least not until I can figure it out.
</span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (Dave Mueller @ Mar 11 2003, 11:17 AM)</td></tr><tr><td id='QUOTE'>
Seems odd to me, using a super-high contrast film and then trying to get 5 or 6 stops of greyscale by using different devlopers. What's the advantage of using lith film? </td></tr></table><span class='postcolor'>
I've used a large variety of litho films and one characteristic that attracts attention is very fine grain. So if you can tame the contrast you have a super fine grain low speed film.
Mind you have to watch what kind of base they are on if you intend to enlarge anything. The cheaper line film made for shooting newspaper pages were kind of semi matte, made that way to be easier to retouch. Litho film designated as halftone film is the highest quality as well as the highest contrast film