Split grade printing question

[Ben Calwell]

I Split-Contrast print with only grades 0 and 5. IMHO, anytime the use of middle grades is used the mid-tones become increasingly contaminated with Green light. Since Mid-Tone contrast is the single most difficult aspect of the Silver print to affect, the less Green or 0 filtration used offers more printing flexibility. This article I wrote maybe of help to those unfamiliar with a deep dive into Multi-Contrast papers. https://unblinkingeye.com/Articles/F.../flashing.html

Steve,
Thanks for the link to your article. I don’t understand the use of green and blue filtration. What kind of enlarger light are you using? I’ve always used yellow filters for low contrast and magenta for high contrast with white light. I have an old Aristo cold light head, and everything I read says I need a 40cc yellow filter to get normal contrast with that head.
I’m trying to come to grips with using VC paper with this head after years of using graded papers. Should I be using green and blue filters instead of yellow and magenta?

[Pere Casals]

What kind of negative needs to be printed with a combination of low grade and high grade filter?

If you are not to burn/dodge then Split grade is the same than using garded paper of a certain grade or using a particular contrast filter grade in VC paper. Insted using a cantrast filter allowing to pass more blue or more green lights you throw the amount od green or blue light by adjusting exposure of green and blue. Red is irrelevant because paper is insentitive to it... so it's the same if you throw green than is you throw yellow, as yellow is green plus irrelevant red.


The difference comes when you dodge/burn during the green or the blue exposure. You may also make the general exposure with (say) grade 2.5 and later burning highlights with grade 0 and shadows with grade 5.


You require split grade when wanting to dodge during blue or green exposure... for the rest it's mostly the same but taking a different path.

When adjusting exposure/grade with regular printing with contrast filters you usually (may) first adjust exposure for the highlights and later you adjust grade to darken shadows to the point you want. With split grade you start adjusting time of green light to adjust your hioglights and later you adjust time of blue light to solve shadows.

There are several recipes to adjust your print... and a bit YMMV. Learn well Split, it's worth, then compare.

[Greg]

Should I be using green and blue filters instead of yellow and magenta?

Back in the 1990s, I had been using yellow and magenta filters for some years. Then read somewhere that two other colored filters could also be used. Don't remember if they were green and blue, but when I tried using them, I had a terrible time honing in on the print quality that I was used of getting, so went back to using yellow and magenta. I personally don't think which pair of color filters you choose to use all the much matters... choose your pair of color filters and just get in there and print and develop your personal technique.

Still haven't found my notes on split printing.... but did dig up some test prints that I had kept after all these years. Looks like I would make a test print with increased exposures going horizontally with one filter, and then repeat with the other filter but going vertically.

Anybody else split printing this way?

Time to spend some time in the darkroom trying to rediscover the technique that I used back then....

[Steve Sherman]

Steve,
Thanks for the link to your article. I don’t understand the use of green and blue filtration. What kind of enlarger light are you using? I’ve always used yellow filters for low contrast and magenta for high contrast with white light. I have an old Aristo cold light head, and everything I read says I need a 40cc yellow filter to get normal contrast with that head.
I’m trying to come to grips with using VC paper with this head after years of using graded papers. Should I be using green and blue filters instead of yellow and magenta?

Thanks Ben for reaching out with questions. The 40cc filter if memory serves is used to neutralize the w54 Aristo cold light head so that the manufacturers "Subtractive" filter paks can be used to control various grades of contrast with MC papers. All MC papers are designed to react to Green and Blue light, green being used to effect soft contrast while the Blue is used to effect the higher contrast layer of the paper. It's important to note, if you are able to use the Green and Blue gels then printing times will be greatly reduced as this is an "addictive" type of color filtration, essentially the exact opposite of manufacturers contrast filter paks, there are reasons they use the numbered system which is not necessary to go into here. Here is a video from my YouTube channel that describes how MC papers work and also illustrates the various different light sources which can be used to use MC papers. https://www.youtube.com/watch?v=uRlq8CwVvws

Unfortunately, at least on my older Mac computer the color rendering of the Roscoe Blue # 68 and Green # 389 is not accurate on my screen. The Rosco gels are very inexpensive and are used in the Theatre industry to colorize stage lighting. So long as you are able to use the filter "above" the negative to alter the color of the light source there will be no degrading of the enlarged image.

[Steve Sherman]

Back in the 1990s, I had been using yellow and magenta filters for some years. Then read somewhere that two other colored filters could also be used. Don't remember if they were green and blue, but when I tried using them, I had a terrible time honing in on the print quality that I was used of getting, so went back to using yellow and magenta. I personally don't think which pair of color filters you choose to use all the much matters... choose your pair of color filters and just get in there and print and develop your personal technique.

Still haven't found my notes on split printing.... but did dig up some test prints that I had kept after all these years. Looks like I would make a test print with increased exposures going horizontally with one filter, and then repeat with the other filter but going vertically.

Anybody else split printing this way?

Time to spend some time in the darkroom trying to rediscover the technique that I used back then....

Hello Greg, see the above post about Green and Blue filtration and the filters used to affect the maximums of Multi-Contrast paper's design. Feel free to ask further questions.

[Greg]

Hello Greg, see the above post about Green and Blue filtration and the filters used to affect the maximums of Multi-Contrast paper's design. Feel free to ask further questions.

Thanks Steve... The two filters that I tried were definitely Kodak gel cc filters cause I was placing them under the lens. An educated guess after all these years (probably 5% "educated" and 95% "guess"), would be that they probably were too weak of filters to use for this application.

[bob carnie]

It has been found that if you are printing with Ilford filters, using a 0 or 00 is a bad idea when using Ilford Warmtone Glossy paper a slight solarizing will happen, therefore I have always use 1/2 or 1 filter as my soft filter. This is not seen with all prints
but well documented on forums in the past.

[Ben Calwell]

Thanks Ben for reaching out with questions. The 40cc filter if memory serves is used to neutralize the w54 Aristo cold light head so that the manufacturers "Subtractive" filter paks can be used to control various grades of contrast with MC papers. All MC papers are designed to react to Green and Blue light, green being used to effect soft contrast while the Blue is used to effect the higher contrast layer of the paper. It's important to note, if you are able to use the Green and Blue gels then printing times will be greatly reduced as this is an "addictive" type of color filtration, essentially the exact opposite of manufacturers contrast filter paks, there are reasons they use the numbered system which is not necessary to go into here. Here is a video from my YouTube channel that describes how MC papers work and also illustrates the various different light sources which can be used to use MC papers. https://www.youtube.com/watch?v=uRlq8CwVvws
Unfortunately, at least on my older Mac computer the color rendering of the Roscoe Blue # 68 and Green # 389 is not accurate on my screen. The Rosco gels are very inexpensive and are used in the Theatre industry to colorize stage lighting. So long as you are able to use the filter "above" the negative to alter the color of the light source there will be no degrading of the enlarged image.

Thank you, Steve. I'll check out your You Tube videos. I have the really old Aristo cold light head, not the newer V54. I'll play around with some filters and see what happens. Thanks to everyone for some great information and advice. I never used VC papers much, so this will be a learning experience.

[Doremus Scudder]

there seems to be a prevalent misconception that exposing VC paper with separate blue and green sources/filtration is somehow superior to other methods. This is simply not true.

VC paper is sensitive to light from the blue end of the spectrum through the green. It's not sensitive to red light. The blue light exposes the high-contrast parts of the emulsion. The green light exposes the low-contrast parts of the emulsion. Intermediate contrasts are achieved by a mixture of blue and green components.

So (assuming the filters are optimal):

Printing through a deep green filter will give you the lowest possible contrast; it only passes green light.
Printing through a deep yellow filter will give you the lowest possible contrast; it only passes green and red light. The paper doesn't see red.

Printing through a deep blue filter will give you the highest possible contrast; it only passes blue light.
Printing through a deep magenta filter will give you the highest possible contrast; it only passes blue and red light. The paper doesn't see red.

Printing through a filter that passes equal amounts of blue and green light will give you an intermediate contrast.
This applies to separate exposures with green and blue light sources, separate exposures with magenta and yellow light sources (both have red, which the paper doesn't see) and a single exposure through a filter that passes both blue and green light together. Examples of this latter are a #2 Multigrade filter, a dichroic enlarger head set to weak yellow or weak magenta filtration (or no filtration), any CC filtration that doesn't eliminate either blue or green completely, and a single exposure with both green and blue light sources.

Most important. If the paper sees the same amount of green and blue light, regardless of the source, the contrast will be the same. It doesn't matter if it's additive or subtractive, comes together, separately, from filters or LEDs or halogen bulbs or in whatever order. It doesn't matter if the blue component goes through a blue filter or a magenta filter; and it doesn't matter if the green component comes through a green filter or a yellow one or if the colors come form green and blue light sources. Furthermore, the mid-tone separation, the micro-contrast, contrast curves etc., etc., will be the same as well as long as the paper receives the same proportion of green to blue light.

So:
Unless you expose different parts of the print with different filtrations, it doesn't matter a whit how you get the contrast you desire.

Split printing only gives different results from any other kind of printing when one dodges or burns with different filtrations. How you want to achieve that, for the prints that need it, is up to you. There are many different ways but no magic bullets. It's just another tool in the toolbox.

FWIW, there are a whole lot of prints that don't need any fancy split printing...

Best,

Doremus

[Joe O'Hara]

Doremus: The engineer in me appreciates the clarity of your explanation above, which I fully agree with.

If someone is getting results that suggest that something else may be going on, I suspect that there may be a problem with your materials, your technique, or your equipment (or a combination thereof).