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? ~m ----- 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 hot, > >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 real > >pain. I know on commercial units there is a sensor which calculates how many > >"units" of UV has been emitted so the operator can compensate. Has anyone > >built a similar switch for the smaller light boxes? > >~m >
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