RE: some observations (and a question) regarding using the sun as a light source

If your negatives are of normal density I would calculate from 5-8
minutes with a 1000 watt mercury vapor lamp with the unit spaced at
about 48" from the printing frame, at which distance it should cover
fairly evenly at least a circle of 30".

Sandy

>Or to phrase my question better: would you have even a rough estimate as to
>what kind of time I'd need to print gum with a 30 inch circle of light using
>a mercury vapor light?
>
>-----Original Message-----
>From: Keith Gerling [mailto:Keith@gumphoto.com]
>Sent: Tuesday, August 10, 2004 5:57 PM
>To: alt-photo-process-l@sask.usask.ca
>Subject: RE: some observations (and a question) regarding using the sun
>as a light source
>
>
>Kate,
>
>What are your exposure times with that light? And how far away is it from
>your print?
>
>Keith
>
>-----Original Message-----
>From: Kate M [mailto:kateb@paradise.net.nz]
>Sent: Monday, August 09, 2004 5:29 PM
>To: alt-photo-process-l@sask.usask.ca
>Subject: RE: some observations (and a question) regarding using the sun
>as a light source
>
>
>I meant to post this a few days ago - been very busy.
>I used to use the sun as a light source. Here in the south Island of New
>Zealand, there is as Catherine says a huge hole in the ozone layer,
>which gives us very high u.v. I was able to print between 10 a.m. and 2
>p.m. without adjusting exposure - in reflected light only as direct
>light would instantly overexpose/fog the print. In the end, because of
>the legendarily bad weather here, I was forced to get an alternative
>light source. I bought a mercury vapor lamp secondhand and that has been
>wonderful.
>It's relatively easy to get secondhand lamps here (wish I'd known this!)
>as a lot of big manufacturers use them as factory lighting. I'm still
>fine tuning exposure times for various types of negative in an attempt
>to find the best combinations for my work, but overall the shorter
>exposure times have made the whole thing much easier. And also, I don't
>have to work to the daylight/weather either.
>
>Kate
>
>
>
>
>
>---
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Received on Mon Aug 9 17:24:44 2004