Durst CLS 450: Reaching VC Grade #5

• the color of the magenta filter?
• does it move into the light beam when you turn the dial?

four-by-five said:

t my enlarger produced was rather simply red. I tried fiddling with the controls, tried literally every single extreme combination and watched the easel as I rotated the dials. Couldn't get anywhere near purple.

Click to expand...

four-by-five said:

Could it be the filters having faded, the wrong bulb/an electrical problem, the head generally being unable to reach that high of a grade or something else entirely?

Click to expand...

DREW WILEY said:

"ancient Polymax" is one obvious clue to your dilemma . Ancient anything would be. Try fresh VC paper.

Click to expand...

four-by-five said:

I ordered some fresh Fomaspeed Variant 313 and followed its data sheet's recommendations of setting 130M on the enlarger. The results were almost identical.

Click to expand...

Patrick Robert James said:

Get your hands on a 47 blue filter or gel. that will max out the contrast.

Click to expand...

bernard_L said:

Did you dis-assemble the color head to perform a visual check of:

• the color of the magenta filter?
• does it move into the light beam when you turn the dial?

Click to expand...

MARTIE said:

I take it the white light setting handle on the lefthand side is in the correct position?

I believe forwards for filter in and back for filters out.

Click to expand...

DREW WILEY said:

You'd have to dial up the Magenta as far as it can go; but that doesn't mean your VC paper itself is up to the job. Paper "grade" spacings vary by specific product line; and VC papers involve a continuum anyway.

The hardest light you can achieve would be by means of just leaving all your colorhead settings at zero, and then putting a deep blue 47 glass filter over your lens. It will be more effective than maximum magenta.

Dichroic colorhead filters do not "fade", technically-speaking. But they can develop grime over time; or even worse, start spalling off bits of coating if overheated for many years, making them less effective.

Papers do not achieve their full DMax potential without post toning afterwards (selenium, gold chloride, etc).

Click to expand...

Paul Howell said:

Now in the distant past. but I was under the impression that VC papers in the 80s to early 2000s could not reach grade 5 or 5, grade 4 was as high you got. Then with paper going on at least 10 years old, if one of the sensitive layers has aged, that could reduce the VC range.

Click to expand...

ic-racer said:

The enlarger needs to be serviced.

Click to expand...

koraks said:

Faded filters: no. Spalling is possible, but I've not personally seen it on any Durst heads.
Bulb: won't make much of a difference even if you manage to get the 'wrong' one in there.
Head in general: nope, that's not it; you should be able to get around grade 4 to 5-ish depending on paper & developer (Fomaspeed doesn't hit a true grade 5 anyway; refer to the datasheet as to what you can expect).

So probably something else. A red projected image sounds like a red filter being stuck in there somewhere. You mention a CLS450 head but not the type of enlarger. Is there a filter layer somewhere with a red filter stuck in? Most Durst enlargers have a red under-the-lens filter that can be swung in the light path; can you confirm this is not under the lens when doing these tests?
There's also a lever on most Durst heads (IDK for sure about the CLS450) that engages the filters; however, with that in the 'wrong' position, you'd get white light, not red.

Note that you can sometimes eek half a grade of extra contrast from a paper by using a blue filter instead of a dichroic magenta filter. However, the gross problem you appear to be describing here suggests something else is wrong, so look at that first. You should be able to get a pretty darn hard grade with a dichroic magenta filter. I've done it lots of times with a Durst dichroic head and Fomaspeed paper.

Click to expand...

darkroommike said:

If you tried your test again with "fresh" VC paper rather than paper that is 25+ years old you might get the contrast you need. That said, for years I printed VC papers with a Durst M601 with the CLS66 color head. 0-100 CMY.

1. The first thing you have to realize is that "Durst" numbers do not equal Kodak CC numbers or Agfa CP numbers. And Durst 0-100 heads do not equal Durst 0-130 heads! Yea!

2. The next thing is that magenta and yellow are opposites, one removes blue light and lowers contrast, the other removes green light and increase contrast, the only reason to use both in a "filter pack" for black and white contrast printing is to attempt to match speeds as you change filtration, which, in my opinion if pointless.

3. What I did, when I needed a lot of contrast was the put a Polymax filter in the filter drawer of my color enlarger, that is the easiest was to get a 5+ contrast with my Durst. I still have sets of both Ilford MGIII and Polymax filters sized for my Durst and another set of 6x6 sized filters for my Omega enlarger.

If you are a masochist, and aren't all darkroom workers masochists, you could also do this with just two "pure" filters, blue and green, and expose your negative to varying combinations of minus yellow and minus magenta light. Too much work for me, but I know the theory.

You could also buy a MG head for your Durst, Durst called that thing a Multigraph. (Good luck with that, I suspect they all got bought up as spares for people already using them.)

Click to expand...

koraks said:

So that's fine.



But with 130M on a Durst head he should get pretty darn punchy grade 4 or so, and given the flat and fogged results, something's going wrong.

PS @four-by-five - what kind of safelight do you use? Please note that Fomaspeed needs a red safelight. If you're using an OC safelight or something similar, this will fog the paper. It can easily explain the flat & fogged prints you got. It doesn't explain the red projected image of course.

Click to expand...

koraks said:

Faded filters: no. Spalling is possible, but I've not personally seen it on any Durst heads.
Bulb: won't make much of a difference even if you manage to get the 'wrong' one in there.
Head in general: nope, that's not it; you should be able to get around grade 4 to 5-ish depending on paper & developer (Fomaspeed doesn't hit a true grade 5 anyway; refer to the datasheet as to what you can expect).

So probably something else. A red projected image sounds like a red filter being stuck in there somewhere. You mention a CLS450 head but not the type of enlarger. Is there a filter layer somewhere with a red filter stuck in? Most Durst enlargers have a red under-the-lens filter that can be swung in the light path; can you confirm this is not under the lens when doing these tests?
There's also a lever on most Durst heads (IDK for sure about the CLS450) that engages the filters; however, with that in the 'wrong' position, you'd get white light, not red.

Note that you can sometimes eek half a grade of extra contrast from a paper by using a blue filter instead of a dichroic magenta filter. However, the gross problem you appear to be describing here suggests something else is wrong, so look at that first. You should be able to get a pretty darn hard grade with a dichroic magenta filter. I've done it lots of times with a Durst dichroic head and Fomaspeed paper.

Click to expand...

koraks said:

OK, if you swing Magenta all the way to the max, you should get magenta filtration. If the light turns red, this means that yellow for some reason is moving along with it. I've never looked inside a CLS450, but on some dichroic heads it's possible that something bumps out of alignment (e.g. during transportation) causing several filters to latch onto each other. Maybe something like this has happened. You would also see exposure times being veeeerrrrrry slooooooow since you'd effectively filter out virtually all of the light the paper is sensitive to.

Click to expand...

four-by-five said:

Hello everyone,

up until now, I've never bothered with VC papers. However, there is a negative that I believe could look quite dramatic in grade 4 or even 5. As I have no fix-grade paper that hard in stock right now, I used my ancient Kodak Polymax. All proper calibration and scientific testing aside, I read that 3Y + 112M would be a good #5 starting point for this paper on a Durst color head (with 130 points max).

So, I dialed in those values on my CLS 450 color head and did some testing. The test prints did not look anything like a hard grade at all, exactly the opposite to be precise. Very low contrast over all, no clean whites, no dark blacks. The paper itself is not fogged, I know that for sure, but I thought that because the paper is quite old aging may have taken its toll on it. I ordered some fresh Fomaspeed Variant 313 and followed its data sheet's recommendations of setting 130M on the enlarger. The results were almost identical.

I grew suspicious that the color projected by the enlarger head was wrong so I watched a YouTube video where someone demonstrates VC printing. The light for grade 5 looked purple/dark pink-ish but what my enlarger produced was rather simply red. I tried fiddling with the controls, tried literally every single extreme combination and watched the easel as I rotated the dials. Couldn't get anywhere near purple.

I've recently replaced the bulb in the enlarger head. It is an "OSRAM ELC 64653HLX A1/259 24V/250W GX-5,3" – AFAIK the right replacement. I recall reading that the filters in the enlarger head are safe against fading but I start to wonder if that's really the case. After all, the enlarger and the head are really quite old now and AFAIK my model came from a photo studio, putting it through heavy use.

All this drove me terribly mad, I really want to figure this out.

So, to sum up: Could it be the filters having faded, the wrong bulb/an electrical problem, the head generally being unable to reach that high of a grade or something else entirely? Picture me puzzled...

Greets!

Click to expand...

Paul Howell said:

As you live in Germany there might be someone in your part of the world that can overall a Drust Color head. Many years ago I had an amamture model the 606 with a color head. a set of colored plastic filters, very easy to clean. In case you don't have it here is a link to the service manaul for your 450.

https://phsc.ca/repair/Durst/durst_enlarger_cls450.pdf

Click to expand...

RalphLambrecht said:

with your printer and color head, you get the hardest grade at max magenta and min yellow. Your filters are unlikely to have faded.These filters are very stable! There is one more thing you can try. Purchase a set of under-the-lens clip-on filters from Ilford and try them. They are very good and also last a long time if kept clean. Other than that, there is nothing else you can do but get the graded paper.

Click to expand...

four-by-five said:

Thanks for the service manual, very helpful! I'll have a closer look at it once I get home. A quick look over it makes it seem a bit intimidating.



Good to know, thanks! Maybe I'll see about such a filter set for the time being, I'll have to make my mind up there.

Click to expand...

RalphLambrecht said:

You should be able to find the Ilford filters secondhand too or borrow them from someone. Have you tried a local camera club?

Click to expand...