Aristo cold head omega D2 enlarger

[Doug Darling]

Can anyone tell me if I'm using a cold head on my Omega D2 enlarger, can I use VC filters. I read somewhere that the light on the Aristo cold head is the wrong wave length for filters.

Doug

 

[Whiteymorange]

First you have to determine which cold head you have. The later versions are color corrected, the earlier have a suggestion for a +40 yellow filter just to make them neutral. After that, the filters can be used, but the results are a bit squeezed toward the contrasty side. I don't have the literature with me now, but Ilford published a guide- I'm sure it's available on line.

 

[jeffreyg]

Doug,

Aristo is no more. You can probably get information from Voltrac ph: 1-203 799-7877 (Louise Kessler ext. 3163) or
email:louise.kessler@voltrac.com

They apparently took over Aristo products. A year or so ago I needed new bulbs for Arist VCL4500 and that's who I dealt with.

http://www.jeffreyglasser.com/

 

[Bill Burk]

Shoot, I haven't tested. I'm partial to graded paper.

Whiteymorange, thanks for the tip. I have the older one with a distinct teal glow. Will try +40 Yellow since that makes sense.

Doug, if yours is older, I may be able to test and give some objective opinion (I don't know - is that an oxymoron?)...

 

[bill@lapetelabs.com]

The Aristo D2HI light source had a v4500 tube in it that required a 40 yellow filter to work with the multicontrast filters, the v54 tubes in the newer light sources is corrected for use with multigrade filters without cc filters!

 

[George Collier]

My first Aristo head had the D2HI bulb (HI for high intensity). It was a clean, slightly cool light, mostly white, and could not be used with contrast filters without the yellow40 fillter, which would slow it down, and, as Whitey says ranged to the contrasty side.
I now have a new(er) V54 lamp with the "distinct teal glow" Bill mentions. This lamp was designed for VC filter printing, and I find that, after 10 years, the gradation change moving up the contrast levels is not linear, exposures not consistent between contrast grades (as promised by Ilford filter info - but not their fault, the filters are designed, I believe, for incandescent light sources), and larger print exposures can be long.
BUT - I have never achieved the quality of print I can make today with Ilford WT MG fiber, using split filtering with this head. I also bought the head that has a 6" filter drawer above the neg, and purchased 2 filter "holder" frames, so I just open the door and slide in the frame when changing filters. The low end filter is extremely flat, the high one extremely contrasty, so splitting the time is a great way to finesse contrast and range. I can also burn in selectively with different grades, resulting in shadow contrast that I don't think you can get with graded paper.

I think it is not so much about the head unit, but the bulb itself, which I assumed is marked somewhat. If you contact Louise (contact info above) she can help - they may be remanufacturing the basic V54 lamp for your head. The history of the company is long and complicated, but appeals from the APUG community have resulted in some of the original line being made available.

Bill - if your lamp is destictly blue green in color, then I think you have the V54, newer, not older. A simple way to test viablilty with filters is to just print on VC paper with no filter. If it is the old lamp, it will be very contrasty. If you get something closer to normal, likely you have the V54. Somewhere on this forum you can find reference to a simple method of blue and yellow (or green) 2-filter method - using only those two colors to make different grades - a cheap way to start.

 

[Bill Burk]

Thanks George, I'll try and see what unfiltered seems to give me compared to filters

 

[jvo]

an aside...

i have a zone VI cold light head for my d2... i needed a new tube for it about 6 years ago... spoke to louise then; she said "i think there's a guy around here who still knows how to make that!" works wonderfully!

jvo