Excessive contrast with VC paper

[DeanC]

I'm struggling with a contrast control problem in my printing I hope someone can help me with.

I'm currently printing with an Omega D6, the variable condenser head and Ilford contrast filters above the negative. When I test with a Stouffer step tablet I'm seeing each filter print between 1 and 2 grades higher contrast than what I'd expect (and what the sample data that ships with the BTZS WinPlotter shows.) It's consistent across Arista.EDU FB Glossy, RC Pearl, and Ilford MGRC Pearl, so I don't think it's just the paper. I'm developing in Formulary 130, 1+1, for 2 minutes but I see similar results with Ilford's Multigrade Developer. The printing of actual negatives is consistent with what I'm seeing in my test data. For reference, the #2 filter is printing with an exposure scale between 0.7 and 0.8 and the sample data seems to say I should expect 1.00 or a little greater.

I'm wondering how much switching to a diffusion light source might control my contrast and if there's something else I should try to tame things a little. I'm recently back from a 20 year break away from the darkroom and I don't remember having this problem back in the day...

Thanks!

 

[Pieter12]

How old are your filters?

 

[DeanC]

How old are your filters?

I had that thought, given that I was using the ones I put in storage 20 years ago, so I bought new ones. No discernible difference between sets.

 

[Paul Howell]

The advantage of printing with VC filters is that can just lower your filter a grade to get the contrast you like. Why the change, could be that all bands of VC paper were lower contrast 20 years ago. I have negatives that date to the mid 60s, these were developed for hard contrasted needed for halftone newspaper reproduction, last I printed these older negatives they printed grade 3 with a grade 3 filter, much newer negatives developed for grade 2 print, that is what I think of as normal grade 2 with a 2, or 2 1/2 to 3 filter. I use Foma VC paper either rebanded or Foma brand RC and FB, and I have some Foma single graded grade paper grade 2 and 3 which seem to match what recall as being grade 2. You can also use split grade printing, I have used this method on occasion. And yes a diffusion head will decrease contrast a 1/2 to a full grade. With a color head it is very easy to print split grade.

 

[Doremus Scudder]

Condenser enlargers print about a grade more contrasty than a diffusion light source will (look up Callier effect).

It's not a problem if you can still find a filtration that works for your negatives. I don't think you need to conform to the BTZS plotter parameters to make good prints. If you do, and if you like the condenser source, then tailor your negative development so that your "normal" ends up on your chosen intermediate grade.

Personally, I like to tailor my negatives to print "normal" at a bit higher contrast (think 45 M on a color head which is about a #3 filter I think). I like the way the prints tone better when printed at a higher contrast setting.

Or, you can switch to a diffusion light source. Dichroic heads are nice to work with and give continuous contrast control.

Best,

Doremus

 

[Pieter12]

these were developed for hard contrasted needed for halftone newspaper reproduction

Just a nit: photos for newspaper reproduction needed to be low contrast, as they gained on-press.

 

[Nicholas Lindan]

Are you using an LED light bulb instead of a PH212?

 

[MattKing]

Are you using an LED light bulb instead of a PH212?

+1 - it could very well be due to the light source.
A daylight balanced incandescent would also be problematic.

 

[Paul Howell]

Just a nit: photos for newspaper reproduction needed to be low contrast, as they gained on-press.

That is stanage as we always shot higher contrast, +1, well for the wire, at UPI we shot pretty much for grade 2.

 

[Pieter12]

That is stanage as we always shot higher contrast, +1, well for the wire, at UPI we shot pretty much for grade 2.

Dot gain, or tonal value increase, is a phenomenon in offset lithography and some other forms of printing which causes printed material to look darker than intended. It is caused by halftone dots growing in area between the original printing film and the final printed result. In practice, this means that an image that has not been adjusted to account for dot gain will appear too dark when it is printed

 

[MarkS]

If you can make prints that look good, I wouldn't worry about it. Unless you're constantly using the lowest-contrast filters; you don't always want to be banging up against the limits.
A diffusion light source will give better highlight separation, but that's an expensive answer. I've preferred them since I made my living as a custom printer, 40 years ago.
Just for starters, you might try Foma papers; I find that their FB VC papers print with lower contrast than Ilford's. Then there's the option of low-contrast paper developers; the Formulary has at least two types on offer.
If you've been away for twenty years, re-test your development time. It's possible that you're overdeveloping; that's pure speculation on my part.

 

[ic-racer]

I'm struggling with a contrast control problem in my printing I hope someone can help me with.

I'm currently printing with an Omega D6, the variable condenser head and Ilford contrast filters above the negative. When I test with a Stouffer step tablet I'm seeing each filter print between 1 and 2 grades higher contrast than what I'd expect (and what the sample data that ships with the BTZS WinPlotter shows.) It's consistent across Arista.EDU FB Glossy, RC Pearl, and Ilford MGRC Pearl, so I don't think it's just the paper. I'm developing in Formulary 130, 1+1, for 2 minutes but I see similar results with Ilford's Multigrade Developer. The printing of actual negatives is consistent with what I'm seeing in my test data. For reference, the #2 filter is printing with an exposure scale between 0.7 and 0.8 and the sample data seems to say I should expect 1.00 or a little greater.

I'm wondering how much switching to a diffusion light source might control my contrast and if there's something else I should try to tame things a little. I'm recently back from a 20 year break away from the darkroom and I don't remember having this problem back in the day...

Thanks!

The diffusion head will also make printing with a glass carrier easier (less prominent dust. Personally I'd just develop the film for 20% less time.

 

[DeanC]

Thanks for all the replies.

The challenge I'm running into is that I'm crammed up at the bottom of the filter range and having a hard time making decent prints when I've got an SBR in the upper 7's to 8, or higher. I mean, I'd like to be able to get "book" results for the paper, or at least understand why I'm not, but getting good prints from contrasty scenes is the goal.

Just addressing a couple other suggestions from above:

-The bulb in there is a 150W PH212. That said, I have a 75W and 250W on the shelf and will give one of them a try. I've done enough mechanical and software troubleshooting to know it can definitely be the thing you're so sure it isn't that you didn't bother to check it.

-Aren't Arista.EDU Ultra papers just repackaged Foma?

-I went through a full round of BTZS testing with HP5+ and Arista.EDU Ultra 100 earlier this year and I've got good good dev times for higher contrast scenes if I can get a decently soft paper.

Thanks again for the thoughts.

 

[MARTIE]

This is so hard to assess at a distance.
What I can say, is that the only times that I've had any real issues with contrast, it's invariably been the negative.

The other thing I've noticed, although I've never used formulary 130, is the following, lifted from the data sheet:

"USING THE DEVELOPER
For normal contrast - prepare the working solution by a 1:1 dilution of the stock solution with water. Develop the print for 45-
60 seconds at 20° C/68° F.
For more contrast - develop the print for 45-60 seconds in undiluted stock solution at 20° C/68° F.
For softer results - dilute the stock solution 1:2 with water, and develop the print for 45-60 seconds at 20° C/68° F"

So, if I understand correctly, you appear to be developing the print for considerably longer 2+ times.
And there is a 1:2 softer dilution option.

Perhaps, you could post a pic of the negative(s) you're having difficulties with printing?

 

[Zathras]

Hi Dean, are you using the paper sample data that came with the software? I believe that those results were obtained either from contact printing the step tablet onto the paper, or, by enlarging the step tablet with a diffusion enlarger.

If you haven’t done your own paper tests, my guess is that the higher contrast that you’re getting is due to the condenser light source, especially since it’s consistent across all the papers you are using.

 

[DREW WILEY]

Yeah, sounds like your negatives might be overdeveloped to begin with. And as far a the condenser aspect to your enlarger, just adding a translucent white sheet of acrylic to your filter drawer will basically convert it into diffuse mode.

You're probably overthinking this, and might not be correctly using the step tablet for test purposes anyway. Aim for practical results instead.

Personally, I always dilute 130 1:3, and develop anywhere from 1-1/2 to 3 min or more (with 2 min being the most common), depending on the exact look I'm trying to achieve. I think it's foolish to force oneself to standardize on only a single time. It's like owning only a single size of hammer.

 

[Lachlan Young]

Omega D6, the variable condenser head

There's your problem. There is nothing wrong with your materials, or your enlarger or the BTZS data - just that somewhere along the line someone failed to explain to you that a condenser head will give inherently higher contrast than the BTZS data derived from contact prints or diffusion enlargements. This is not a new problem, though to listen to this thread of rambling, you'd think it was. Not so long ago, manufacturers used to publish data with different negative development starting times for diffusion or condenser enlargement - and tables that clearly defined the differences required in negative aim density range for a given paper exposure scale between average diffusion and condenser sources. And the whole point of the BTZS approach is intended to enable you to refine your negative exposure and development time to match your enlarger's light source characteristics for a given paper exposure scale...

 

[chuckroast]

There's your problem. There is nothing wrong with your materials, or your enlarger or the BTZS data - just that somewhere along the line someone failed to explain to you that a condenser head will give inherently higher contrast than the BTZS data derived from contact prints or diffusion enlargements. This is not a new problem, though to listen to this thread of rambling, you'd think it was. Not so long ago, manufacturers used to publish data with different negative development starting times for diffusion or condenser enlargement - and tables that clearly defined the differences required in negative aim density range for a given paper exposure scale between average diffusion and condenser sources. And the whole point of the BTZS approach is intended to enable you to refine your negative exposure and development time to match your enlarger's light source characteristics for a given paper exposure scale...

This.

Condenser, Point Source, & Diffusion/Cold Light sources all have different effects on print contrast.
Although Zone System has its limitations, one of the many things it gets right is that you have to calibrate your film EI and development protocol for your light meter, your thermometer, your timer, and yes, your paper exposure light source (not to mention your preferred final look in the print).

 

[glbeas]

Dot gain, or tonal value increase, is a phenomenon in offset lithography and some other forms of printing which causes printed material to look darker than intended. It is caused by halftone dots growing in area between the original printing film and the final printed result. In practice, this means that an image that has not been adjusted to account for dot gain will appear too dark when it is printed

If you know what you are doing with halftones it doesnt matter so much as you think. The dot gain is accommodated by proper exposure and development along with the proper bump exposure to bring up shadow detail. Midrange contrast on the print was important to make the image reproduce well.

 

[Paul Howell]

Although I minored in Photojournailsm, we did not study how a print was processed, but thinking about it, producing higher contrast prints might have more to do with the "look" editors wanted. By the 70s I don't think I was ever told by an editor that she/he wanted a high contrast print.

 

[MattKing]

Although I minored in Photojournailsm, we did not study how a print was processed, but thinking about it, producing higher contrast prints might have more to do with the "look" editors wanted. By the 70s I don't think I was ever told by an editor that she/he wanted a high contrast print.

This - plus the fact that if the photo ended up being printed on newsprint using a high volume and fast press, a photo that offered soft contrast and subtle tone transitions tended to lose detail and just lie whimpering on the page, while a contrasty and very graphically strong photo - which also lost some detail - otherwise tended to jump out and grab the customer/reader's attention.

 

[DeanC]

Hi Dean, are you using the paper sample data that came with the software? I believe that those results were obtained either from contact printing the step tablet onto the paper, or, by enlarging the step tablet with a diffusion enlarger.

If you haven’t done your own paper tests, my guess is that the higher contrast that you’re getting is due to the condenser light source, especially since it’s consistent across all the papers you are using.

I have done the tests, that's what prompted the post. I'm getting grade 4 level contrast from the #2 filter. I expected the condenser head to produce more contrast, just wasn't expecting two grades. Especially given that I don't remember getting results this contrasty before.

 

[DeanC]

There's your problem. There is nothing wrong with your materials, or your enlarger or the BTZS data - just that somewhere along the line someone failed to explain to you that a condenser head will give inherently higher contrast than the BTZS data derived from contact prints or diffusion enlargements. This is not a new problem, though to listen to this thread of rambling, you'd think it was. Not so long ago, manufacturers used to publish data with different negative development starting times for diffusion or condenser enlargement - and tables that clearly defined the differences required in negative aim density range for a given paper exposure scale between average diffusion and condenser sources. And the whole point of the BTZS approach is intended to enable you to refine your negative exposure and development time to match your enlarger's light source characteristics for a given paper exposure scale...

No one failed to explain that, my original post even asked how much softer I could expect a diffusion head to print. A 2 filter is giving me roughly grade 4 contrast and I just don't know if 2 full grades difference is reasonable to expect between condenser and diffusion.

Plus, this is the same enlarger I was using 20 years ago and I don't remember having this problem with MGIV and Multigrade developer back then.

 

[Lachlan Young]

No one failed to explain that, my original post even asked how much softer I could expect a diffusion head to print. A 2 filter is giving me roughly grade 4 contrast and I just don't know if 2 full grades difference is reasonable to expect between condenser and diffusion.

Plus, this is the same enlarger I was using 20 years ago and I don't remember having this problem with MGIV and Multigrade developer back then.

2 grades difference is about where most well controlled comparison tests end up. What may also be happening is that you are no longer producing the same sort of negatives as 20 years ago in terms of exposure to process relationships - and some paper curves have changed from MGIV, which could distort your previous outcomes if you were printing by perception rather than purely relying on densitometric analysis.

 

[DREW WILEY]

Also sometimes depends on how old your step tablet is, and if it has yellowed in the interim.