Help with Zone IV coldlight!

[ic-racer]

I had similar issues with a cold cathode light. I made a center filter for it but eventually gave up and got a dichroic head.

[Craig Roberts]

I also observed this and it cost me a lot of hair untill... I replaced the tube, they don't last forever and that solved the problem. Craig

[5063]

you have to change the configuration of the top bellows when you switch to 4 x 5. At least you do on the Beseler unit which I have. (you have to move the light father away from the negative the larger the negative gets).

This is wrong. It is true with condensers, but not with coldlight. The light should be in the lowest position, as close to the film as possible.

[Robbie Bedell]

Craig, Thank you! That is the direction I am going. I have wanted to get the new Aristo V-54 tube, but I was afraid that after I make the replacement I might still have the same problem. But if it cured your woes maybe that's what I should do. The LED light I am looking at is about $270 vs. about $180 for the Aristo so staying with flourecent makes sense...

http://robbiebedell.photoshelter.com

[DennisD]

It's been years since I had my Arista cold lite head, ( identical to Fred Picker's Zone 6 head ), but, as I recall, the lite sat directly above the negative carrier in the compartment that previously housed the condensers. There was one diffusion disc and a filter to correct the light color. The light was very even.

I know my 5x7 Aristo head has a temperature /heat pad to keep the light even and start at full brilliance, but don't recall if the D2 version has the same. However, a bad heating pad could be a source of uneven light. Does the light even out if kept on continuously for a several minutes - I.e after the tube warms up ? - If so, the heat element, if there is one, or the tube may need replacing.

[Robbie Bedell]

Thanks Dennis. I did check the heater and it is working just fine..

http://robbiebedell.photoshelter.com

[Sal Santamaura]

Nature of the beast. See my post #36

http://www.apug.org/forums/viewpost.php?p=841843

in this thread:

http://www.apug.org/forums/forum172/64914-aristo.html

[Robbie Bedell]

Thank you Sal, In fact, during my research, I had come across your earlier apug posts. The strange thing here is that what I am experiencing is not just a little 'edge-dodging' but a lot. I would say it goes a good one-third the way toward the center of the photo and, I am guessing here, about a two stop difference from dark to light. What I am trying to determine now is that one: perhaps the bulb is going and two: will a new Aristo V-54 bulb help? I have been in contact with Louise at Voltec and am about to buy a bulb but I do not want to throw good money after bad....Robbie

http://robbiebedell.photoshelter.com

[Bill Burk]

Robbie,

What grade were you working at? I made prints from two different negs so far on my Aristo grid and I don't see the uneven lighting on those prints. Well, one print seems to have edge burn but I "did" burn that edge. It's just darker than I expected. The other print seems absolutely even.

Anyway, I was working at Grade 2 which may be less sensitive to the effects of uneven light distribution.

I hope I don't have to make a center filter because it looks like a good bit of work.

[Merg Ross]

Robbie, glad you contacted Louise at Voltec; she has been very helpful over the years. I have had the Aristo V-54 bulb on my DII for about ten years and it has performed beautifully. I added a dimmer, as the light is very bright, and also very even. Hope this will be the solution to your problem.

Merg