Print exposure times for lith paper?greenspun.com : LUSENET : B&W Photo: Alternative Process : One Thread
I'm about to embark on some lith printing trials and have read that paper exposure times are significantly longer (I have read Tim Rudman's writings on lith).
I have a home build variable 450 watt incandescent head on a modified Zone VI enlarger and will be using 4x5 and 5x7 negs in a glass neg carrier. If I were to start with a strong Kodalith solution as recommended by T.R. at about 70 degrees to start with, what time increments on the test strip should I begin with? He suggested 30 second increments but I have a lot of lumens I can pump out with this head.
The reason I ask is that I use a beeping electronic timer that only goes to 60 seconds before going silent - which is fine for traditional paper. If my exposure times get into the minutes then I need to get a different timer before my first session.
TIA - doug
-- doug mcfarland (email@example.com), February 01, 2001
Do you mean lith film? I've never heard of lith paper. But anyway... I suggest you do a first test with full stop increments: say, 5, 10, 20, and 40 seconds. That should get you in the ballpark. Just as an example, let's say 20 seconds is closest to correct, but you want to try some 1/4-stop increments around 20 seconds. Your next test exposures would be 14.1, 16.8, 20, 23.8, and 28.2 seconds (exact 1/4- stop intervals above and below 20 seconds).
The benefits of using 1/4-stop intervals really become apparent when you get above 40 seconds. For instance, you could use three second intervals--say 14, 17, 20, 23, and 26 seconds, and you would still be close to the precise 1/4-stop times. But when you get up to 40 seconds, your three-second intervals will be off: say you use 34, 37, 40, 43, and 46. Well, the correct 1/4-stop intervals (surrounding 40) are 28.2, 33.6, 40, 47.6, and 56.4 seconds.
See my article at:
-- Ed Buffaloe (firstname.lastname@example.org), February 02, 2001.
Thanks Ed - This will help.
... and yes, lith paper. I have some Sterling Process Lith paper on the way and plan to try some Kodalith developer on the process lith paper as well as my "old standby" Oriental Seagull graded.
I also have Tim Rudman's Lith printing book on order but it'll take a while for it to arrive. Rudman has some wonderful examples of lith printing with non-lith negatives in his Master Printing book.
Anyhow - I've read that exposure times could get into the several minutes range, and development time for weak lith developer in the 1/2 hour range. This should try my patience. doug
-- doug mcfarland (email@example.com), February 03, 2001.
Rudman's book is a wonderful resource. I am entrenched in the digital darkroom presently, and unable to launch off into lith printing. it sounds extraordinarily fun, so please keep us posted.
-- daniel taylor (firstname.lastname@example.org), February 06, 2001.
Thanks Daniel - I've been surprised at the lack of information about this process, both in print and web based. I'm even having problems locating a local book store that carries TR's Lith printing. I got my first batch of lith paper and it's marked blue sensitive - so I have to put up red lights this week :-) I'm so used to OC - this should be an experience. doug
-- doug mcfarland (email@example.com), February 06, 2001.
The is only one truly lith paper is distributed by Photospeed (former sterling). Other papers are very good for lith prints: Oriental Seagull is is a good one as Maco (Cachet ?) papers. The are all graded papers and contrast control is done by exposure/developent (snap time). The technique I use for determining exposure is making a normal test print in normal developer, then using THAT exposure but I open 1 stop.
-- Marc Leest (firstname.lastname@example.org), February 07, 2001.
Thanks Marc - I have just received my order of Sterling Process Lith paper, and I do have a stock of Oriental Seagull graded that I plan to experiment with as well.
One stop at what I presume is normal dilution of lith developer, so I'll guess that I need to be in the ball park of 2 to 3 stops with a dilutiion of say 6 or 8 to 1. When I'm cranked to 450 watts I run grade 3 exposures at about 15 seconds at f8, so that would take me to 90 to 180 seconds. It sounds as though I'll need a different timer.
That really answers my question - thanks to all that responded.
-- doug mcfarland (email@example.com), February 07, 2001.