cold light versus vc cold light

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Hello all,

Actually, I've got two questions:

1) I'm looking to purchase a standard cold light head for my used 4x5 Beseler. I've been a bit overwhelmed searching through the cold lights at B+H's site because there's not a lot of detail supplied with each of the products listed. I've noticed that many of the lights are listed as 220 Volt, to which I do not have access in my apartment. For anyone "in the know", would the Aristo w/ V54 lamp and Beseler collar (adapter) do the trick? I realize I may be asking a question which has an obvious answer, but I'd like some piece of mind from the members of this forum before taking the dive. A simple "yes" will do.

2) I'm a bit hazy on the beauty of the variable contrast cold lights. Is it the ability to perform "split printing" in a single exposure? Perhaps I don't quite understand the art of split printing but can't the exact print quality be achieved by using a cold light with vc filters (even if two exposures are necessary)? To a degree, I understand the vc cold light's ability to fine tune exposure separately in shadows and highlights, but I guess I just don't understand how one can justify the $700 price difference between using a standard cold light head w/ variable filters and using a vc cold light head. The main reason I'm asking of course is that I'm intrigued by what the vc cold light can offer. Admittedly, I haven't even seen the side by side difference between a condeser light source print and one made via cold light, let alone the difference between standard cold light head and vc cold light.

Thanks in advance for any responses. Greatly appreciated. Love this forum!

Kevin

-- Kevin Blasi (Kevin.Blasi@home.com), July 29, 2001

Answers

I would like to address the VC cold light head vs. cold light head with VC filters. Having started with a cold light and doing split development in Selectol Soft and Zone VI developer using graded papers I thought I had a pretty good system. After the latest generations of VC papers came out I dabbled, using VC papers and VC filters with the cold light. Lousy experience. Great images. Why? VC filters just aren't made for a cold light. They are to widely spaced and can make exposures painfully long. Good theory, bad practice.

But the results were there; the split printing allows to you to "easily" control high light and shadow values.

Now, move to a VC head, mine is a Zone VI. By utilizing a couple of different techniques you are working with 2, 3 or however many "grades" on one sheet of paper. (When you move to this type of printing "grades" become moot. You are in a realm of tones and texture where you are going for the right "look" not a grade value.)I start with a test using the soft light only, establishing my high value exposure. Print a picture at that exposure and do a test strip with hard light only over it. This time I look for the low value only. After determining that time I make a print for the soft light time, turn it off and turn on the hard and print for that time. All this while NEVER touching the negative stage of the enlarger. Now you have determined an overall "contrast" (I prefer tone and texture) for the image you can use your test strips to determine if there are areas of local contrast that can be adjusted. Could the high values be a bit harder, maybe a shadow could soften up just a bit. I feel this is as close to toal control in the darkroom as there is. A real low tech photoshop that still requires you to get your hands wet with smelly chemicals!

-- Marv (mthompsonn@home.com), July 29, 2001.


Kevin, I second Marv's experience. Actually, I now use two enlargers, an ancient 8x10 Elwood with a cold light and a Beseler 23C with an Aristo VC cold light. The only thing I don't like about the VC head is that the light is dim. When it's on blue only (hard) you can barely see the image - a problem if you want to dodge anything. Not so bad with blue/ green mixed, which is how I usually use it, but still dimmer than my old Aristo non-VC cold light, and slower. However, it's not really any slower than using filters grades 3 and up.

On the Elwood, I put a #15 green gel on the cold light to make it the right color to use filters, then I use regular Ilford contrast filters. Talk about slow, some of my exposures on that are 6-8 minutes for large mural prints. I am now very happy with my Aristo VC head.

-- Sandy Sorlien (sand44@mindspring.com), July 29, 2001.


The general consensus seems to be that differences between cold lights and condensors are minimal once your negatives are tailored for the light source.

1/ I haven't used a Beseler but the answer should be 'yes'. A V54 should work fine with your Beseler and will work fine with VC papers. Older cold lights had a minor problem with VC papers. Their light was too blue heavy (VC filters were probably calibrated to tungsten sources). So, the contrast was often higher than what one would expect from the filter number. This could be compensated for by some calibration but the second problem was that older cold lights put out very little green light, thus making it very difficult to get the lowest contrasts from the VC paper i.e., the problem is one of efficiency - if you wanted to print using green light, the cold light was inefficient, most of the light was wasted, and it is too efficient in thee blue region (since the calibration of the filters was to tungsten sources). The V54 is supposed to be optimized for VC (which probably means it emits well into the green and probably has efficiencies matched). Anchell says he was very impressed with it.

2/ Variable contrast cold light heads obviate using filters. You have two tubes, one emitting blue light and one emitting green light and you mix these lights to get the contrast you want. So, split filtering is still done through two exposures but you can change the setting at a dial and avoid jiggling the enlarger head or lens stage etc. I'm sure they are very easy to use but they have always been too pricey for my blood (but then heck, I haven't even sprung for a V54, I continue with the old W45 tube or whatever is in cold light head).

Cheers, DJ

-- N Dhananjay (ndhanu@umich.edu), July 29, 2001.


Kevin: There is a 110V V54 head which will fit your enlarger. (Is that a simple "yes"?) Call Aristo and ask, they are incredibly helpful. They will even suggest retailers who will give you a better deal than they will on the product which is right for you. I tried using yellow filters to adjust the older Aristo head I had to work with modern VC materials. Better, but pretty hopeless, contrast can be untameable. Though manufacturers of paper suggest that you can filter the light with yellow filters, Aristo will tell you it won't work and in my experience they are right. The V54 head (weird aqua light output) works great with the Ilford filters set I've used for it. I don't find using the filters an objectionable hassle. They seem to have zero effect on sharpness, even when used below the lens. If money is no object, then I can see why a head with adjustable color outfit would be a convenience. The modern VC papers are much better than what I was using when I gave up on VC years ago, particularly the VC Seagull fiber based paper.

-- Kevin Crisp (KRCrisp@aol.com), July 29, 2001.

That's weird, Kevin #2, it was the Aristo guy who told me to use one or two #15 green gels on a regular cold light and it does work. But not as predictably as their VC head.

-- Sandy Sorlien (sand44@mindspring.com), July 29, 2001.


Hmm, don't know what to say. What day of the week did you call? Seriously, my question to them was very specific, about a factory head for the 8X10 Beseler, maybe yours is a different color? The newer heads seem to offer very nice speed. I relamped both the 8X10 head and my old Omega B22XL and both work great. There was no amount of filtering with the old one which would get me below about grade 4.

-- Kevin Crisp (KRCrisp@aol.com), July 29, 2001.

I've used an Aristo VCL 4500 head for about five years. There are only two advantages to the VCL head as compared with filters: (1) it's much more convenient - you don't have to fool around with changing filters every time you want to change the contrast; and (2) the Aristo, and I think all other variable contrast heads, has gradations of one tenth as opposed to one half with filters, allowing for somewhat finer contrast adjustments without the hassle of using two different developers (e.g. Dektol and Selectol Soft to achieve a similar effect). The convenience factor is very important to me. I often make burns in one or more areas of a print at a different contrast than the basic print, sometimes several burns at several different contrasts, and there's simply no comparison between the ease and convenience of doing this with a variable contrast head as compared with trying to do it with filters.

-- Brian Ellis (bellis60@earthlink.net), July 29, 2001.

My name is John and you can reach me at 1-800-CALUMET ex 3351. I can go over the differences with you without being a salesman. There are major differences between the two and the one you choose should be based on what type of printing that you do and where you want to go with it. I'll be in 7-30 and 7-31 but then wont be back until 8-12 then I'm here every day.

-- john (dogspleen@juno.com), July 30, 2001.

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