Re: STARTING POINT
Hi Bob Excuse me joining in late from the antipodes. You may perhaps have a focus problem using variable contrast enlarging paper in a large format camera. Ctein reports in Post Exposure that some vc emulsions are extraordinarily sensitive to the uv end of the spectrum which the human eye can't see to focus. Of course he was testing with enlarger lenses, which may perform differently from camera lenses, but he found the plane of focus for uv was as much as 12mm away from the visible plane of focus at about 10x enlargement for the Kodak paper he was using. If this is a problem then I guess a uv filter would solve it, but at the expense of a good deal of speed because it seems the paper has little sensitivity above green. Don Sweet ----- Original Message ----- From: "BOB KISS" <bobkiss@caribsurf.com> To: <alt-photo-process-l@usask.ca> Sent: Friday, April 18, 2008 1:21 PM Subject: RE: STARTING POINT > DEAR JEAN & GREG, > Thanks 2U2! > CHEERS! > BOB > > -----Original Message----- > From: Gregg Kemp [mailto:gregg@roanokesound.com] > Sent: Thursday, April 17, 2008 8:02 PM > To: alt-photo-process-l@usask.ca > Subject: Re: STARTING POINT > > ISO 6 is a good starting point. Working with pinhole cameras for 30 > some years, I favor low contrast graded papers. Most recently I have > been using Oriental Seagull grade #2 from Freestyle camera and like it > a lot. > > Gregg > > On Apr 17, 2008, at 3:20 PM, BOB KISS wrote: > > > DEAR LIST, > > I recall in the distant past that there had been some discussion of > > using silver gelatin enlarging paper in a view camera, eg, 4X5 sheet > > film > > holders to produce a paper negative. > > What I am hoping for is a starting point for an equivalent "ISO" > > speed for the paper. Even a ball park would be great for me to start > > testing. I know that it will vary with manufacturer and other > > variables but > > it is nice to have some idea to save time. > > I am not worried about image quality.I am just trying to get an idea > > of some suggested ISO. > > Thanks in advance. > > CHEERS! > > BOB > > > > > > Please check my website: http://www.bobkiss.com/ > > > > "Live as if you are going to die tomorrow. Learn as if you are > > going to > > live forever". Mahatma Gandhi > > > > > > Gregg Kemp > gregg@roanokesound.com > http://www.greggkemp.com > > > __________ NOD32 3035 (20080417) Information __________ > > This message was checked by NOD32 antivirus system. > http://www.eset.com >
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