U of S | Mailing List Archive | alt-photo-process-l | Re: Some Lights It Hot, Some Lights It Cold

Re: Some Lights It Hot, Some Lights It Cold

No fan. I've never felt the insides get more than warm to the touch. So, I
ran my stouffer wedge under five different strips from the same coated
sheet. The difference was less than I thought, one-third of a stop, maybe
less. So I'm chasing the wrong bug. Is it possible for a inkjet negative to
lose more density even after it's "stabilised" due to multiple exposures?

----- Original Message ----- 
From: "Sandy King" <sanking@clemson.edu>
To: <alt-photo-process-l@usask.ca>; <alt-photo-process-l@sask.usask.ca>
Sent: Thursday, March 08, 2007 9:10 AM
Subject: Re: Some Lights It Hot, Some Lights It Cold

> This is called a light integrator. It calculates how much light has
> fallen on a specific area and measures the amount in units, as water
> meters measure volume.
> Light integrators are necessary with the HID (high density discharge)
> lamps used in plate-burners because the intensity of the light is not
> 100% until the unit has been on for a minute or so. However,
> radiation is 100% with BL fluorescent tubes within 5-10 seconds of
> turning them on and does not change much even with long exposures,
> unless the tubes and ballast get hot.
> Do you have a fan installed on your unit? If not, I would install a
> fan before worrying about an integrator.
> Sandy King
> At 8:22 AM -0600 3/8/07, Michael Koch-Schulte wrote:
> >Forgive me the headline, I'm atoning for a life of typos...
> >Seriously though, I have a real question... I use a bank of UV BL
> >fluorescents to print my work (a la Eepjon). I've been weeding out the
> >errors, big and small, in my process lately. I find that when the are
> >used within the last half hour, they are anywhere from one-third to
> >two-thirds a stop faster than when the lights are "cold". The difference
> >makes printing to highlight and calibration (using the term loosely) a
> >pain. I know on commercial units there is a sensor which calculates how
> >"units" of UV has been emitted so the operator can compensate. Has anyone
> >built a similar switch for the smaller light boxes?
> >~m