From: Sandy King (sanking@clemson.edu)
Date: 11/27/02-11:54:40 AM Z
Jeff,
That is correct.The surface of my probe is perpendicular, or at a
right angle, to the printing surface, and about 25" distance from the
tip of the bulb, almost on a straight line from it. The key is that
wherever you place the probe it should always read the same, and from
there it is merely a question of calibrating the time units. I have
my unit calibrated so that one unit of exposure is almost exactly
equivalent to one second of exposure. This allows me to work with
seconds and minutes if I prefer, after the 7 minute warm-up of the
lamp.
Sandy
>Sandy: Thanks. See my response to Clay. I already tried to "stop down,"
>with no improvement, but I throw out another approach there.... As far as the
>positioning of the probe, are you saying that the face of your probe is flush
>to a surface (the wall) perpendicular to the printing surface (table top)? -JB
>
>
>Sandy King <sanking@clemson.edu> said:
>
>> Jeff,
>>
>> I think Clay has correctly identified your problem. If you look at
>> the probe there should be a screw which when turned will allow you to
>> rotate the dial in such a way as to decrease or increase the amount
>> of light that can pass through to the photo-sensitive diode.
>>
>> BTW, I would also suggest that you place the probe a few inches away
>> from the printing area to avoid having to move it when you actually
>> print. My probe is mounted on a vertical wall about 25" from the tip
>> of the bulb, almost on a straight line, and I get very reliable
>> readings from this position.
>>
>> Sandy
>>
>>
>>
>>
>> >Jeff:
>> >
>> >My Nuarc unit has a little aperture device above the integrator
>> >cell, sort of like waterhouse stops on old lenses. The idea is to
>> >rotate around to holes of differing diameters - smaller diameters
>> >admitting less light of course. It sounds like you need to restrict
>> >the amount of light reaching the photocell in some manner. Does your
>> >device have something similar, or could you rig up something like
>> >that if it doesn't?
>> >
>> >Clay
>> >
>> >On Wednesday, November 27, 2002, at 09:42 AM, Jeff Buck wrote:
>> >
>> >>To Those Who Weighed In On Integrator Issues Recently: I got hold
>> >>of an Olec "Olix AI 950." Having trouble calibrating it for my HID
>> >>lamp, which is a 1000W metal halide lamp and is positioned 34"
>> >>above the printing surface (from bottom tip of the massive lamp
>> >>bulb). I positioned the probe on the printing surface looking up
>> >>at the lamp. I then commenced the attempt to calibrate the
>> >>integrator for this light source. No good. No matter where I set
>> >>the probe dial (you rotate it back and forth to let more or less
>> >>light reach the photo cell itself), the read-out numbers raced by
>> >>like Seabiscuit. The numbers ran from 00.0 to 99.9 (or 000 to 999)
>> >>in about a minute and a half. The manual says nothing about the
>> >>capacity of the integrator to handle any particular maximum of
>> >>light. Comments? -jeff buckels
>>
>>
>
>
>
>--
This archive was generated by hypermail 2.1.5 : 12/17/02-04:47:05 PM Z CST