After acquiring an Omega D5 XL enlarger a few months ago, I've finally been able to put together a makeshift darkroom and have started printing a few 4x5 b&w negs that I developed. I've outfitted the D5 with an Aristo cold light and a Rodenstock 150mm lens. I've done some rather rudimentary printing so far just to play around, and I have a couple of questions that have me perplexed. Please excuse me if the questions seem naive.

1. I cannot get the lens to focus close enough to print on an 8x10 piece of paper no matter how far I extend the bellows or how low I crank the neg./lens stage. Is it impossible for me to print on 8x10 with a 150mm lens? Am I relegated to 4x5 contacts and printing on 11x14 and up?

2. Installing the cold light necessitated the removal of the filter drawer. How can I use contrast filters now? Can I place 6x6 in. filters between the neg. carrier and the light, or should I just forget it now that I'm using cold light and go with graded paper?

Thanks for your responses. I'm just getting my feet wet in b&w, so I apologize if my questions seem painfully simple.

-- Dan Blair (hiker1017@yahoo.com), December 26, 2001

Answers

Under the lens there is a lock and it can be used to extend the bellows. This is in addition to the round knob used for a fine focus adjustment.

If you have the more recent version of the Aristo cold light (called VL45?) you can use vc filters under the lens or 6x6 filters on top of the negative holder. The latter method does not allow for easy filter changing. Aristo sells the newer tubes for about $100. It is worth the cost. The color of the newer light is "green."

-- Louis Jensen (jenluc@ix.netcom.com), December 26, 2001.

Dan, Don't be afraid of using a below the lens filter, they work just fine. No real proof exists that they cause any problems as long as they are clean and kept close to the lens. I have an Omega D5 and the Aristo cold light head. No problems printing with the 150mm Componon- S at 8x10 and smaller. I suspect the earlier response was on target, you need to adjust the lens stage by releasing the lever behind it.

-- Dave Schneider (dschneider@arjaynet.com), December 27, 2001.

I am not an expert on this point, but I don't think you can use variable contrast filters to vary the contrast with a standard cold light head. I have the D5XL and I used to have the Arista head. With that combination I was limited to graded papers for contrast changes. Then I got the Zone VI variable contrast cold light head so that I could use vc papers. It has two tubes: one for magenta, the other for yellow light output. The contrast depends on the relative intensity of the magenta and yellow lights. I think Arista makes a similar vc cold light head. As the other writers have indicated, you should be able to make 8 x 10 enlargments with a 150mm lens by extending the bellows.

-- John Boeckeler (boeck@midcoast.com), December 27, 2001.

I regularly use contrast filters under the lens with my standard cold light lead. I cannot tell you exactly what contrast grade they produce, nor do I care as long as the print looks like I want it to look. I do know that the lower contrast filters produce lower contrast prints. It may be a slightly higher contrast than with the light designed for filters. In any case, a little experimenting will show you what the filters do. I have also not noticed any loss of sharpness with the filters under the lens. It doesn't show up in the prints nor under the grain focuser.

Regards,

-- Doug Paramore (Dougmary@alaweb.com), December 27, 2001.

To calrify, I have the Aristo head with the V54 lamp.

-- Dave Schneider (dschneider@arjaynet.com), December 27, 2001.

The original Aristo cold light heads used the W45 tube that is not compatible with VC filters due to the bluish color of the light (similar to older style florescent lights). In theory, the W45 tube can be corrected with a filter, but this reduces the light output quite a bit. These older Aristo (and some Zone VI) cold light heads are the kind that are usually available on eBay. They work great on fixed grade paper such as Ilford Gallerie and Oriental Seagull (and others).

Aristo now uses the V54 tube in their heads which is color corrected and compatible with VC filters. Replacement V54 tubes for older Aristo heads are available from B&H Photo or directly from www.aristogrid.com for about $125. The only problem (as already noted) is that the cold light head does not have a filter drawer like many condenser heads they replace. Some people have made their own filter drawer, or they insert the filter next to the frosted plastic diffuser (you will usually need to custom cut the filter to do this). If you put the filter on top of the negative carrier, care should be taken to ensure that the filter is not within the depth of focus of the enlarger lens.

Aristo (and Zone VI from Calumet) also makes a fairly sophisticated VC cold light enlarger head that does not use filters to achieve variable contrast. As mentioned above by others, this is accomplished by using 2 cold light tubes of different colors, which are varied by an attached controller to achieve the desired contrast. These heads cost about $1000.

-- Michael Feldman (mfeldman@qwest.net), December 27, 2001.

One additional note: Aristo Grid Lamp Products, Inc. is often confused with Arista, which sells film, paper, and chemicals (supposedly manufactured for them by other companies). These two companies are completely unrelated.

-- Michael Feldman (mfeldman@qwest.net), December 27, 2001.

The V 54 bulb that Arista now uses does not give a filter grade # that coorelates with "accepted" graded papers. The set up should be tested with a step wedge to see what "correct" grade # comes from what filter #. As an example Ilford VC FB paper with a #2 filter gives about the same contrast as #3 graded paper on my set up. George

-- George Nedleman (gnln@thegrid.net), December 27, 2001.

Well, at least I was right about one thing. I'm no expert. After reading the subsequent responses, I went to The Variable Contrast Printing Manual by Steve Anchell (Focal Press 1997). He discusses variable contrast printing with cold light heads (pp. 56-59, 106- 111). Happily for you, the Aristo V-54 is a single-lamp cold light that is optimized for printing vc papers with paper manufacturers' filter sets designed for subtractive printing.

-- John Boeckeler (boeck@midcoast.com), December 27, 2001.

Dave Schneider said he has the V54 tube, but Dan Blair (the originator of this thread) has not said (and may not know) what tube he has.

-- Michael Feldman (mfeldman@qwest.net), December 27, 2001.

If Dan Blair has the W45 or W55, he should refer to Anchell's book at pp. 109-111.

-- John Boeckeler (boeck@midcoast.com), December 27, 2001.

Thanks for all the helpful responses. I don't know which cold light tube I have; I'm away for the holidays but will check when I return home. (Although I find it's a real pain in the neck to get that cold light assembly out once it's put in place.) I'll definitely get a hold of the Steve Anchell book.

Thanks again.

-- Dan Blair (hiker1017@yahoo.com), December 27, 2001.