Question Jim Galli!

[jon.oman]

For the "Arista APHS Premium Halftone Supreme Ortho Litho Film", I have read that the normal ISO of 6 to 12 can be used. Since this is very slow, I wonder about reciprocity. Have you experianced this problem, and if so, do you have a suggested correction amount, for various metered times?

Thanks, Jon Oman

[jon.oman]

Does anyone have any ideas on this? I would like a starting point, so that I do not have to burn too much film/time to find out!

Jon

[Bjorn Nilsson]

Without knowing anything about this particular film, slow film does in general have "better" reciprocity characteristics than faster film. E.g. a Tmax 100 does need less exposure than TMY or even TMZ when the exposure times are going into the minutes.
Also, lith film is/was normally used for copy work, where normal exposure times is in the second(s) range, not e.g. 1/60 sec. So the whole "normal" scale is moved some 6-10 steps. Given this, reciprocity failure would start being noticable when the meter indicates 1-2 minutes or so.
A link about this:
http://www.usask.ca/lists/alt-photo-process/2002/may02/msg00290.html

One of the advantages of using lith film is the nice price tag, so burning say 6 sheets of film to find out will not cost you more than a single sheet of TMX. Apart from that, you will have even more detail in the lith shot than with TMX.

//Björn

[jon.oman]

Thanks for the information, and the link. It's good to know that it will not be much of a problem.

Jon

[Jim Galli]

My own experience is seat of the pants. Like telling someone to add a dash of salt to the gravy. It is very different from normal film we're used to. It acts more like paper. So if I calculated a minute exposure I'll bet I would give it a minute and 45 seconds. Film at a minute exposure would be like 12 - 15 minutes. I use asa 3 for mine.

[jon.oman]

My own experience is seat of the pants. Like telling someone to add a dash of salt to the gravy. It is very different from normal film we're used to. It acts more like paper. So if I calculated a minute exposure I'll bet I would give it a minute and 45 seconds. Film at a minute exposure would be like 12 - 15 minutes. I use asa 3 for mine.

Thank you Jim for the information.

Jon

[walter23]

Film at a minute exposure would be like 12 - 15 minutes.

Whoah, that dramatic? I usually just winged it and gave 1 minute readings about 2 or 3 minutes.

Of course my only experience with this kind of exposure time tends to be in the fading twilight so I just open up the shutter and leave it until I'm finished a cigar or get cold; I rarely actually track a proper exposure time in fading light on B&W film.

[Tim Meisburger]

Walter, I wish I could print my visual image of you sitting there "Oh well, my lips are burning, must be time to close the shutter".

Classic.

[Allen in Montreal]

....

until I'm finished a cigar or get cold......

Cold? In Victoria? I wish for only that kind of cold! :)

[redrockcoulee]

Cold? In Victoria? I wish for only that kind of cold! :)


And Walter is very puzzled why his negs he shoots in Victoria are so dense compared to those from last year in Cowtown, and cigars seem to not to last as long as he is not even cold are they are finished.