Folks,

The only time I've tried to use my 4x5" Graflarger thus far was to print on resin-coated variable contrast (VC) Kodak paper.

The images were a little lacking in contrast, but I attributed this to my first 4x5" sheet film processing more than an enlarger fault. I wonder if the fault lies in the VC paper being affected by the greenish light of the cold light head in the Graflarger. I am asking because I've read this can be an issue with VC papers.

Any experience to that effect?

Should I switch to graded paper instead?

Thanks in advance,
Micah in NC

<font size=-1>[ This Message was edited by: Micah in NC on 2006-04-16 21:29 ]</font>

First a disclaimer - I am not familiar with the Graflarger, however I do know how VC paper works.

Ilford (and I assume others) VC paper has two emulsions on it - one is sensitive to a narrow band of green light, and is very low contrast, the other is sensitive to a narrow band of blue light, and is very high contrast. In an enlarger with a condenser head, the white light is filtered by the VC filters so that varying ratios of blue and green light hit the paper - varying the contrast depending on the filter used. When using a color head, you do the same thing by changing the filtration in the head. For a cold light head, some of them have a narrow spectrum, which would make the filters behave differently and could well skew the contrast range from what was anticipated by the manufacturer.

One thing that you might try is split grade printing, where you use two filters, one which blocks out all the green light, and the other blocking out all the blue light, do two exposures, and the relative difference in exposure time between the two filters will select your contrast. If your head is pretty greenish, you may need to have much longer exposure times on the high contrast filter to get normal results.

A Graflarger is a cold light source, and those are regarded as less contrasty than a condenser light source. So you should probably expect a negative that had successfully printed on a #2 filter with a condenser to need a #3 for the same contrast level with the cold light.

And the cold light also has the reputation of minimizing the effect of dust spots on the negative.

BTW, my Graflarger documentation stresses that the light should be allowed to warm up for about five minutes before use, to allow the tube to stabilize its output. So avoid just setting it up and using it without the pre-heat.

I'm not familiar with the Graflarger either; in my darkroom I always used Ilford VC paper and Ilford filters in my Beseler 23CII. IIRC, and it's been a while, using Ilford VC paper without any filtration gave you the same as a grade 2 paper (probably the instruction sheet that comes with the paper will tell you), although a #2 filter was also included in the Ilford set---go figure. But as disemjg said, you have to consider the light source too.

Is there any provision for using VC filters on the Graflarger? My hunch is probably not, since I assume that the Graflarger pre-dates the introduction of VC paper. I'm really out of my depth here, but I think the suggestion to use graded papers is a good one, and may be your only option, if you can't make the VC paper work one way or another.

https://graflex.org/helpboard/viewtopic.php?topic=382&forum=12

Henry

The reason the Ilford include the #2 is that the filters are doing 2 things - they are adjusting the ratio of blue:green to achieve the appropriate contrast, and they are also trying to keep the overall exposure the same across contrast grades (there is a step, I think at about grade 4), but for the most part, if you have an image where the exposure is correct with 15sec at f8, and you want more contrast, you can just change the filter and keep your exposure time and aperture the same.

Mark

Aha! Many thanks for the explanation.

Make sure you have the right tube in it. The old ones will give nothing but headaches with VC paper. The newer Aristo tube is made to correct that.

Most people have the opposite problem with older cold light heads like the Graflarger and VC paper--too much contrast--so they add around a 40Y filter to get a normal result with a grade 2 filter.

In any case, work with it for a while with different negatives shot under a variety of lighting conditions and see if there are any general tendencies, and don't be afraid of using a #1 or #5 filter if that's what the image calls for.

If you're committed to VC paper, Aristo can upgrade your Graflarger to a V54 tube, which is more compatible with VC papers. I think the website is http://www.aristogrid.com, and if I remember correctly, the conversion is around $100-150.

Personally, I usually prefer graded paper anyway.

<font size=-1>[ This Message was edited by: David A. Goldfarb on 2006-04-19 20:15 ]</font>