Got the De Vere, now need more contrast

Hi all,

Finally got the De Vere home in one piece, and have started trying it out. It

sure feels well built, and the low focusing knobs are a great design feature.

I've been using a condensor enlarger so far for my 6x6 and 35mm work, and some

of the flatter negs which I print at G4 on it can't barely get enough contrast

at full magenta filtration on the DV dichro head. I tested it w the ilford

filters too, soo it seems to be a diffusion effect. Now, I know about the

contrast difference between cond and diff sources, and have just re-read the

relevant section in Ctein's book, but am still a bit surprised at how little

contrast I'm getting at full strength. I still have to reprint my important

6x6 work to see how it looks, and before I remodel my very small darkroom to

fit the DV and remove my Durst condenser, so I'm curious if this is something

you just live with using a diffuser head, and from now on just aim for

contrastier negs, or whether there's a way to squeeze more contrast out of thhe

diffuser and therefore not have to keep the condenser around. Anyway, learning

all the time, glad to get some experienced input,

GB

"I still have to reprint my important 6x6 work to see how it looks..."

Well, at least you have *important work*...

Change to a different paper developer or developer dilution...?

"I'm curious if this is something you just live with using a diffuser head, and from now on just aim for contrastier negs..."

Yep. If you want to use the diffusion head, then you have to come up with a longer tonal scale negative. I like to give the film more exposure to gain shadow detail and only increase development slightly. You need a longer scale negative. How you achieve that is up to you.

"...whether there's a way to squeeze more contrast out of thhe diffuser and therefore not have to keep the condenser around."

Nope. You either control the film for the diffusion head or for the condenser head.

Change to a different paper developer or developer dilution....?

You SHOULD be able to get a condenser head for the DeVere!

If you cannot, and the above suggestion regarding chemistry and different paper does not, then try graded paper!. If that does not work, then push the thing into the corner and get a good MF enlarger. Leitz Focomat IIa/c enlargers are tops, and cheaper than ever. Or if you haven't enough MF prints to make to justify another enlarger, I suggest you consult with the custom printers at, for example, Gamma in Chicago. They are so good I am sure you will be surprised.

I have no idea about the DeVere head but you seemed to be asking about diffusion heads in general so I'll mention that I had no trouble getting plenty of contrast from an Aristo VCL4500 head. It's a dial head that goes from 0 to 5.1 in increments of tenths. When I attended a Phil Davis workshop Phil did some measurements for me that showed a paper grade of about 4.5 with the head dialed to 4.5 or very close to that. So I don't think diffusion heads necessarily lack the contrast to the degree that you seem to be finding.

Your problem, it seems to me, is that your negatives were developed to a contrast range suited for your old, higher contrast head, and now you're trying to reprint them on a lower contrast head. I think that's just going to be a problem with your old negatives, there isn't a whole lot you can do about it, the negatives are what they are (assuming, of course, that there isn't something of a mechanical nature that can be done to produce a higher contrast with your new head). Well that's not quite true, you could try selenium toning your old negatives to increase contrast but that's a time-consuming and somewhat risky proposition, and even when it's done it only increases contrast by about a half stop equivalent. But of course for any new negatives in the future you can redo your EI and development time tests so that new negatives are processed for your new enlarger's contrast characteristics.

Your problem is likely a combination of the diffusion head and color filtration. You might try using a G5 VC filter below the lens for your old negs.

Regarding new negatives made for your new light source, the above poster was right when he wrote that you need to match your new negs to your new light source, but he was wrong about how to do it. Increasing exposure alone REDUCES contrast, increases grain, and reduces sharpness. To increase contrast, you'll need to increase development, and you might find that the increased development requires LESS exposure, especially if you habitually overexpose, as many do. Good luck.

Jay

IF more contrast is desired, then ponder both the film and the techniques used to expose and process. Some film inherently have more contrast; this is certainly true of many slow films in the 25 --> 50 speed range. Some film developers are also more contrasty in nature, and increased agitation as well as pushing the film will certainly add contrast. Or you can pick papers and paper developers that provide higher contrast, plus use toning techniques that add selectively to highlight density.

I also suspect that the color head on the enlarger may not be the best choice for VC papers. Perhaps you need to explore that issue with another enlarger that has a true B&W Variable-Contrast head.

It's normal for a diffusion enlarger to print silver negatives to lower contrast than a

condenser enlarger. This particular problem is that you have some especially flat

negatives that needed grade 4 paper with a condenser enlarger, so now with a diffusion

enlarger you need the equivalent of grade 5 paper, which doesn't exist. The best

solution for future negatives is to develop a bit longer to increase the contrast of the

negatives so they typically print on your target grade paper.

Since you got the same result with Ilford VC filters as with the dichro head, there doesn't

seem to be anything wrong with the color head. You could try using both full filtration in

the head and an Ilford filter to see if you can get a little bit more contrast. One other thing

to check is that you don't have any contrast reduction from stray light, e.g., safelight

fogging.

If these flat negatives are important to you, either you need to keep your current

condenser enlarger, find a condenser head to sometimes use on your DeVere, or try

intensifying the negatives (e.g., Selenium).