I have recently made the tests for determining the contrast of VC paper outlined in Steve Anchell
fs The Variable contrast Printing Manual and was shocked to find that the highest contrast that my diachroic Saunders VC head will print is a range number of 105, equivalent to a grade two paper. I am using Oriental Seagull FB VC with Oriental Oritone cold tone developer. To make sure, I also tested with Ilford Multigrade developer 1:9 and got similar results. By the way, the lower contrast end of the scale goes way down below a grade 1 paper, and I could achieve an RN of 275, which is completely useless for all practical purposes.

So I am left with the option of either changing paper, changing developer, changing the light head, or adapting my film development. Changing the head is not an option for now, and the paper I would rather not change as I have taken a liking to it (unless someone has a good alternative of course). I wouldn
ft mind changing the developer if I could find the same rich cool tones and a much higher contrast in another developer (enough to push the whole thing at least one grade up). I usually process my film to fit a grade 2 paper, but I may have to develop it for grade one to give myself a little leaway on the higher contrast end of the scale (which would yield more grain, but then again with 6x7 it might be ok). Does anyone have similar problems, and any suggestions to get out of this unexpected VC quagmire. Thanx

-- Raja Adal (d60w0635@ip.media.kyoto-u.ac.jp), August 15, 2000

Answers

Hi Raja, I don't know anything about the Saunders VC head, but it seems to me there is a problem with it. Could you bypass the head and use VC filters? If nothing else, using the filters might help you isolate the problem.

chris

-- Christian Harkness (chris.harkness@eudoramail.com), August 15, 2000.

Greetings Raja,

I haven't tested all my materials using Steve's methods, but I did test Ilford MGIV (FB & RC) Oriental Seagul (RC) Kodak AZO, grade 2 and AGFA MC. I used a Kodak liquid developer (not Dektol) and an Omega Dichro II color head.

Using these papers and the Kodak developer the highest contrast I can get is a grade 3.5, even the graded AZO tests out at least a full grade lower. The highest contrast I've been able to get is with Oriental paper. BTW all of the papers tested were selenium toned.

I suspect that I may need to try a different developer and or check my water to achieve a higher contrast. I'm about to try ethol LPD. As far as the light source, I have changed lamps with no dramatic effect on contrast chage and that wouldn't account for the grade 2 AZO printing at grade 0.5 to 1. For me this isn't a real problem as I usually produce contrasty negs and having low contrast papers helps. With Ilford MG I can go way down to a grade 000, or -2. Very handy for printing Tech Pan negs with a max D of > 2.0 d.u.

Good luck and let us know what you find.

Regards,

-- Pete Caluori (pcaluori@hotmail.com), August 15, 2000.

Some suggestions, first do an effective test of your safe light. Go to the Kodak site and follow their instructions for doing a safelight test. If you are getting some fog from your safe light and are trying to get rid of it by reducing your exposure this will cause a reduction in contrast. I think that this is a cause of a lot of problems for people using VC papers.

I would also suggest diluting your developer a little more than is recommended and increase your development time. When you put the paper in the developer watch for how long it takes for the image to begin to appear, I would multiply that time by at least 4 or 5 for your total development time. If the image appears in 45 seconds then 45 x 5 = 225 or 4 minutes. Try these things and I think you will find your contrast ranges start falling into place.

-- Jeff White (zonie@computer-concepts.com), August 15, 2000.

Something is not right. Yes, you could have a safelight fogging problem. Do the highlights look especially muddy? Most VC papers give grade 2 with unfiltered tungsten light. Do your tests indicate this. If not there is a problem with your testing method. Prints are developed to completion, so changing developer or extending development time will change contrast less than 1/2 a grade or so. I assume your highest contrast check was with full magenta and no yellow. Did the image on the easle look deep magenta? The filters could be faded or the mechanism sticking (I've seen that before). I personally adjust film development so that a photo of a contrasty sunlight scene prints well without filtration, then add magenta or yellow seperately to adjust. I don't think about grades or blending yellow and magenta for constant exposure.

-- Tim Brown (brownt@flash.net), August 15, 2000.

Two things:

I see from your URL that you are in Japan. Has the enlarger been connected correctly for the voltage there? (100 VAC?). If not, then the bulb may not be getting enough voltage which will cause it to be dimmer & redder than expected causing much lower contrast & greatly increased exposure times.

I would try getting a blue filter and place it in the illumination light path somewhere. Since the high contrast part of the emulsion is sensitive to blue, this will decrease the green & red & should increase the contrast. When I started using a coldlight with VC paper I had to add a green filter to reduce the blue & reduce the contrast. I got the filter gel sheet from a cinemtography supply house - about $5 for a 1 meter square sheet.

Cheers,

-- Duane K (dkucheran@creo.com), August 15, 2000.

Re Azo: My tests also show that grade 2 Azo is much longer-scaled than a traditional grade 2 and doesn't correspond to the data on Kodak's web page. My tests of other papers give more normal results, so I think it's the paper, not my methods. Those who use Azo extensively (e.g., Michael Smith) report that one of its characteristics is its long tonal scale.

-- Chris Patti (cmpatti@aol.com), August 16, 2000.

Tank you for all of the helpful responses.

In fact, with your help I think I have pinpointed two reasons for the low contrast:

1) I have gotten hold of some Ilford Multigrade IV Deluxe RC, and although the contrast started out at way below grade I, it ended at a good grade V. Multigrade IV Deluxe RC is of course, as Anchell's tests show, perhahps the paper with the widest contrast range on the market. I will try to get my hands on some Mutltigrade FB to test it soon. So at least part of the problem lies with Oriental paper, which just has trouble giving a condensed tonal range and higher contrast, although it remains a wonderful paper for high and normal contrast negatives.

2) The other suggestions actually helped me improve other aspects of my enlarger. Duane convinced me of the absolute need to get a transformer to get the voltage from 100 to 120. I had noticed a flicker in the lamp, but had never imagined that lower voltage could change its temperature. Although the safelight test I did when I got the darkroom setup, this time I hung a black cloth all around my enlarger to prevent all stray light from reflecting, and put black electrician's tape to block the openings on the top and side of the enlarger, and to keep the light from slit for the negative holder from reaching the easel. Redoing the tests with Oriental after all of this, the highest contrast was still a grade 2, but the lower grades were more evenly spaced, I am not sure exactly why.

As Tim suggests, if I need a little higher contrast, I will just develop to completion, and if I need much higher contrast will use Ilford or another type of paper. Longer development times are sometimes OK, but there is no way I am ever making my standard development time for all pictures 4 instead of 2 minutes!

I was interested in the discussion of AZO's low contrast. I have concluded that while almost all film tests discuss a testing of the film, film tests done without a densitometer and by printing SHOULD ALWAYS begin with a testing of the paper, before testing the film. This is rarely if ever mentioned in the film test articles I have seen, and is all the more crucial now that we have VC.

Will keep you updated if any new finds come to light! Raja

-- Raja A. Adal (d60w0635@ip.media.kyoto-u.ac.jp), August 30, 2000.

You might want to try LPD. Its great, lasts for up to a year and does not irritate skin (main reason I ust it). As to tech pan contrast, all of my negatives print out at 1 1/2 to 2 on Ilford MG, although I tend to print slightly contrasty anyway. Look in the archives of the film form to see discussions about how to handle TP development.

-- Gene Crumpler (nikonguy@worldnet.att.net), August 31, 2000.