Color Starting Points/Correction Tips for Beseler Dual Dichro S

[ac123]

I've been printing RA4 for some time using my Beseler Dual Dichro S (23c II), though lately have been feeling frustrated at the amount of test prints I've been going through before reaching a neutral or usable color cast.


In the manual for the dual dichro, it states the starting point as 50m 90y, which seems uncommon (?) I have mostly seen the starting point listed online for other enlargers around 50y 50m, or else where the 2 numbers closely match. I am wondering if this starting point dissonance is causing more extreme value differences in color correcting.

It seems also unusual that I need to move the dials in increments of 10 or more to really see any noticeable difference on the print. On other forums/other enlargers, I've seen users comment about changing the dials in smaller increments like 3-10 up or down and it makes a significant difference in tone. For me, a change like that would be very subtle, and almost unnoticeable if there is already a heavy tone in one direction on the print.




Within my notes of "correct" prints I've made, the final color notation can vary with seemingly no consistency or relation to the starting point. A few values of "color correct" prints I've made read like:

y80 m 140
y50 m 140
y100 m130
y90 m110
y35 m110
y105 m140
y100 m190

With values that can range so fully from 1-200, it feels like I am never sure where exactly to "start" when printing a fresh negative, and to have to correct with increments of 10 or 20 feels a little heavy handed.



I understand how the Y/M combination moves around the color wheel, as below, however I'm having trouble when starting out with a negative to begin in some place of "white" "neutrality."

For example, see latest frustrating color print:

Does anyone have any experience/advice on printing on the Dual Dichro, or any tips on the fastest way to achieve a "neutral" print when printing a fresh negative? Thanks in advance.

 

[Robert Ley]

When I printed color, I used a Beseler 45 with a Beseler 45S color head. This was after using a Beseler/Minolta 45 head and a Beseler Universal Color head. I had a Fujimoto CP-51 processor so my processing was consistent and repeatable. I never in probably 15 years had an experience like you. My color head could make changes that were noticeable to me in the 1-2 cc range.
You don't mention what paper that you use or how you process it, those are important factors. I suspect that your dichroic filters in your head may be fading, other than your processing, I can't think of a reason why your filtration values would be that high.

 

[ac123]

I never in probably 15 years had an experience like you. My color head could make changes that were noticeable to me in the 1-2 cc range.
You don't mention what paper that you use or how you process it, those are important factors.

Yeah, it's been quite confusing, but also this is the only color head I've used, and been printing on for a year and a half. I suspect this is not normal adjustment range but was not sure, since the suggested starting points were already so far apart.

Printing on Fuji Crystal Archive Type II.
Processing in a drum in a JOBO temp bath (30 deg C) with 1:40 dev and 1:00 blix.


Re: fading, a quick google search gives me mixed opinions on whether it's even possible for Dichroic filters to fade or not... if not, maybe the wacky CC settings are a quirk particular to this color head?

 

[btaylor]

Those CMY settings are wayyyy out of what I would consider normal- I also find 50Y 50M generally a good starting point, and increments of 5cc are very noticeable in a print. I don’t remember what head I had that did this, but the dials moved the cc indicators but the filters themselves hardly moved because of mechanical resistance (something was stuck). I think I lubed the cams and shafts. You could be moving the dials but not having the filters move proportionally. Just a thought.

 

[koraks]

Does anyone have any experience/advice on printing on the Dual Dichro, or any tips on the fastest way to achieve a "neutral" print when printing a fresh negative?

Not specifically with this enlarger, but I'm used to working with 'weird' filter settings on my own digital light sources. The ultimate conclusion is that the numbers just don't matter. They're all relative, so don't fuss over the numbers being far off where the manual would lead you to expect them.

The fastest way I know of when working with unknown/new negative/scene lighting/paper combinations is to straddle the filtration you expect to end up at. Ideally, make four test strips:
* Far too high magenta, far too high yellow. This print will come out too green + blue = cyan.
* Far too high magenta, far too low yellow. This will come out too green + yellow = lime.
* Far too low magenta, far too low yellow. This will come out too magenta + yellow = red.
* Far too low magenta, far too high yellow. This will come out too magenta + blue = violet.
If the overall balance isn't too the side indicated (cyan, lime, red, violet), you know your filter setting isn't extreme enough on one or both channel(s). Fix that before continuing.

With a little experience, you can then pick a point that's likely much closer to the final filtration for both channels. Do one more test strip and evaluate where it lands; you can then use this as another benchmark for any further strips.

Visually, it would be something like this. The dotted bar represents the neutral point you're trying to establish. This is not necessarily smack in the middle of the extremes you happen to choose. The consecutive strips are indicated with their dominant color casts. Note that strip 5 ends up being a variant of #2, so you know you have to compensate the same way as if you had obtained the #2 strip, just a smaller adjustment.

Of course, once you've figured this out for any given roll, the rest is basically just printing off at very close filter values to be only adjusted for e.g. changes in scene lighting. Assuming you're aiming for neutral, true-to-life prints in general.

 

[ac123]

Not specifically with this enlarger, but I'm used to working with 'weird' filter settings on my own digital light sources. The ultimate conclusion is that the numbers just don't matter. They're all relative, so don't fuss over the numbers being far off where the manual would lead you to expect them.

The fastest way I know of when working with unknown/new negative/scene lighting/paper combinations is to straddle the filtration you expect to end up at. Ideally, make four test strips:
* Far too high magenta, far too high yellow. This print will come out too green + blue = cyan.
* Far too high magenta, far too low yellow. This will come out too green + yellow = lime.
* Far too low magenta, far too low yellow. This will come out too magenta + yellow = red.
* Far too low magenta, far too high yellow. This will come out too magenta + blue = violet.
If the overall balance isn't too the side indicated (cyan, lime, red, violet), you know your filter setting isn't extreme enough on one or both channel(s). Fix that before continuing.

Thanks for this Koraks, this is really helpful, will give it a go.

In regards to the numbers being relative... since the CC adjustment scale seems to be so far off from the "starting points" given for this enlarger, would you recommend using this method at extreme ends of the scale, then dialing in via 10cc at a time?

i.e. printing these:

20 Y , 180 M - too lime print
180 Y , 180 M - too cyan print
20 Y , 20 M - too red print
180 Y , 20 M - too violet print

then picking one of the 4 options, and compensating with 10-20cc adjustments?

 

[koraks]

I'd start on the extreme side and then adjust through consecutive sessions once you get a feeling for what kind of values you end up with.
In terms of adjustments, take big steps, especially at first. So if you start with a 20/180 split, then definitely adjust with something like 50CC for the first guess in-between the initial split. You're generally better off making bigger than smaller adjustments.

What really takes (wastes) time, is inching your way to the end result, and this has another drawback to boot: you tend to accommodate to the color bias, so when you come back the next day, you realize you actually didn't even get where you need to be. It's a whole lot easier to pick a good middle ground between a print that's too magenta and one that's too green, than to try to make a further step based on two prints that are both too green. Being able to see what you get if you overshoot the mark is really useful.

 

[xkaes]

I've used the Dual Dichro S years ago, and the 45 Dichro S today, and haven't noticed any difference in use. Sometimes you need a big change in filtration, sometimes not.

Do you have any viewing filters for color adjustment? That saves a lot of testing. I use the Kodak Color Viewing filters where you simply use your eye on a dried print and make the adjustment.

Beseler (Universal Color Calculator, below) and Unicolor make matrices where you make an actual print by laying the grid on a 4x5 piece of paper:

Either saves a lot of time & paper & chemicals. You can probably find either for about $10 -- in like new condition.

 

[rharter]

I have a Dual Dichro head and feel like I'm in the same situation. I've only been printing for a couple of years, so assumed it was just me (and it still might be). I don't notice much difference with small changes to the filters, and have a hard time finding a decent white point. I haven't solved it, but am following along for the great suggestions.

I recently ordered a Beseler Subtractive Calculator #8916 on ebay (the closest I could find to that Universal Color calculator), so we'll see how that helps. The "large swings" approach @koraks mentioned also sounds promising!

Thanks for posting this!

 

[ac123]

I'd start on the extreme side and then adjust through consecutive sessions once you get a feeling for what kind of values you end up with.
In terms of adjustments, take big steps, especially at first. So if you start with a 20/180 split, then definitely adjust with something like 50CC for the first guess in-between the initial split. You're generally better off making bigger than smaller adjustments.

What really takes (wastes) time, is inching your way to the end result, and this has another drawback to boot: you tend to accommodate to the color bias, so when you come back the next day, you realize you actually didn't even get where you need to be. It's a whole lot easier to pick a good middle ground between a print that's too magenta and one that's too green, than to try to make a further step based on two prints that are both too green. Being able to see what you get if you overshoot the mark is really useful.

Realizing I never properly thanked you Koraks, this was the most helpful advice I've been given in RA4 printing and it sped my process up considerably. The "large swings" approach really helped me understand how each negative + enlarger combo is truly specific to its own relative color swings and how it's futile to follow any preset color points, you pretty much have to feel out your own system.

 

[koraks]

That's great to hear, thanks so much!

 

[Mr Bill]

It seems also unusual that I need to move the dials in increments of 10 or more to really see any noticeable difference on the print.

Hi, I have a couple of things that should probably be said. From a big-lab background I've been involved with a lot of color problems. If someone needs ~10 cc filter change to see a noticeable change in the print I would suspect one of the following: 1) the filter adjustments are not working properly, 2) the print viewing lamps are deficient (spectrally), or 3) you, personally, may have a color vision deficiency (some sort of color blindness). Fwiw it's also possible that your printing exposure or processing have some problems that are counteracting your filter adjustments.

First thing I'd do is verify your print viewing lamp. Some of the worst things you can have are energy-saving fluorescent lamps, which include compact fluorescent bulbs. Don't even consider using these for critical color-balancing work. If you need a reality check on your test prints use outdoor light coming through a window (it will have a full spectrum, even if the color temperature is off).

If you are male there is something like a 5 to 7% likelihood that you have some sort of a color "blindness." This could be in a fairly narrow color range, and you might have never been aware of it. There's not any really good simple method to check. But... the likelihood of color blindness in females is very low. So if a lady friend DOES see an obvious color difference in test prints, whereas you (I'm assuming male) don't, this would suggest a color vision deficiency. In the right situation it could be possible that you think your color head is not making changes to the print, whereas the reality is (could be) that the changes actually ARE happening but you are not able to see them.

As a general rule of thumb, with respect to the effect of printing filtration changes, 1cc change takes a fairly fine eye to see (and for most people their processing will not be consistent enough to produce the change. At 2cc change most serious photographers would be able to notice a color difference between two prints, albeit small. By 5cc filter change it would probably be significant enough that most serious photographers would be inclined to reprint (even though few customers would notice the color being off). By a 10cc color filtration change, this is pretty significant.

If I were trying to troubleshoot an inconsistency in a dichroic lamp head I'd probably do a series of test exposures, changing filtration in some fixed increment, maybe 10cc increments. Just a small test patch is enough; you could expose through a slot in a black cardboard mask so as to keep all of your exposures on a single sheet of paper; this gives processing consistency.

FWIW I'd use a different method of dialing in color corrections, but it's sorta a case of too many cooks spoil the broth. So if your current method is working, so be it. One thing I would always recommend, if you are willing to spend the time, is to print a color ringaround of a typical negative. In our labs we would use something like an 18 exposure series. There would be a "normal" (ideal color) then 3 color strength offsets in each color. This would include a cyan to red (cyan is "minus" red) sequence, with "normal" in the middle. Then a magenta to green sequence, and a yellow to blue sequence. The way you would use the ringaround is like so: you make a first test print from a new negative. Say the color is way off but you don't know exactly what it is. So you compare it vs your ringaround to see what it is closest to. Then reverse the color filters used in the ringaround and you should be pretty close. The ringaround also serves as a reference to re-zero your vision. As koraks mentioned your color vision WILL adapt as you go along. So it is necessary to frequently "reset" this by looking around at the real world, or at your "normal" reference image.

 

[DREW WILEY]

It's hard to say what condition the filters are in, or how clean they are. CC increments also differ between different kinds or brands of heads. The additive RGB Beseler Universal head actually can produce 1 or 2 cc visible increments in a print; but that doesn't correspond to what a typical CMY colorhead does.

I've use multiple color heads. With today's Fuji RA4 papers, when calibrating a new batch of paper, I typically start around cc 30M, 30Y; but might go up to 50M, 50Y, or at low as 20M, 20Y. After that, it's all about fine tuning per image.

Those old Kodak yellow-pouch viewing filter sets are OK for giving one a general impression which way to go; but in my experience, they are a far cry from what comparable colorhead settings actually achieve.

Dichroic filters do not technically fade. But some of the coating can crack and spall off over a long period of usage, especially if the colorhead has been routinely overheated. More often, the problem is accumulation of grime. Cleaning these old filter is a tricky task. Sometimes, it's a mechanical issue in the movement of the filters or their dials.

 

[koraks]

one of the following:

Or 4: it's a temporary "condition" that resolves itself after some more experience is gained. It also helps to look at samples side by side, literally. But I think we all recognize that color 'acumen' so to speak is an acquired skill. While it does depend on physiological requirements, that's not the full story.

I'd say that among starting amateur printers reason 4 constitutes up to 95% of the cases of "hm, 10cc looks kind of subtle to me". After a few hundred prints, most of them will go "oh jeez, I'm miles off still, looks like it could be 10cc or so, if not more!".

 

[Mr Bill]

Or 4: it's a temporary "condition" that resolves itself after some more experience is gained. It also helps to look at samples side by side, literally. But I think we all recognize that color 'acumen' so to speak is an acquired skill. While it does depend on physiological requirements, that's not the full story.

I most definitely agree. I'm just trying to point out a couple of out-of-the-norm situations that are not well-known. But in these specific situations a more-or-less "normal" photographer might find themselves powerless to color correct past a certain degree, thinking that they simply have not developed the skill. So if they are the one in twenty males, or whatever, with significant color vision deficiencies, it's useful to know that up front.

Or, if one is trying to use energy-efficient fluorescent lamps they might well not realize how misleading the specs can be. The biggest culprit is when one make of these has an "acceptably high" color rendering index (CRI). One would think, oh, this ought to be good for color correcting prints! But not so. Long story short the lamp manufacturers long ago learned how to "game" the CRI system. They can adjust the mix of phosphors to do well on the CRI "test objects" but at the same time perform poorly with actual color photographs. Bottom line is, don't try to use em for critical color work. (Plenty of actual experience examining such lamps.)

 

[DREW WILEY]

Consumer lighting tends to have a very significant BS Coefficient with respect to CRI, color temp, and bulb life ratings. Pro Architectural Grade lighting is another story; but those kinds of bulbs cost ten times more (and are generally worth it, since they last way longer too).

Actual color matching tubes are an even higher category; and again, they don't come cheap. I have them at the retouching station outside the darkroom, and used them at the color matching stations where I formerly worked.