Printing Ilford MG Classic and Cooltone with a Zone VI VC enlarger

[Edward Pierce]

I have a Zone VI Type II VC enlarger. To achieve a “normal” or “grade 2” print with a normal full scale negative on Ilford Cooltone or Classic, I have to turn the contrast controls almost all the way to soft. Looking at the data sheets for these papers, I can see why; they are indeed higher than normal contrast.

This problem is only with these two papers. Ilford Warmtone, Adox MCC, Foma 111 and Oriental all work fine.

Turning the contrast controls almost all the way to soft isn’t great. Very small adjustments of the hard light results in big jumps in contrast. I think the controls work best near the middle of their range.

This is with D-72 developer. Back when I used Dektol I had the same issue.

My workaround has been to develop in Ansco 120 (similar to Selectol Soft), either alone or as a divided developer with D-72. Using a softer developer, I can keep my contrast controls near the middle of their range with these papers.

Wondering if a anyone else has encountered this issue, and how you deal with it.

[cowanw]

The one thing you can do is close your fstop by 1 and then double your time, which will increase your ranges.
My controls are broken in so far as varying the intensity of the blue and green lights. Thus I am required to use split light controls, for example today- 10 time units of green and separately 2 units of blue (about Grade 1 1/2). When I first started I used a graded Stouffer negative to graph grades by time units of each colour. Now I just eyeball the negative and estimate the separate green and blue exposures and then adjust to correct effect. I work between f8 and f11 to allow for enough range for fine tuning of the blue units.
I think the split grade technique here, while perhaps a bigger pain, yields a better understanding and good control; over the issue you have.

Grade/ Blue Green /Stouffer steps (21)

5/ 100% 0% /5.5 steps

4.5/ 80% 20%

4/ 76% 24% /6 steps

3.5/ 52% 48%

3/ 43% 57% /8 steps

2.5/ 35% 65%

2/ 28% 72% /9 steps

1.5/ 22% 78%

1/ 18% 82% /10 steps

0.5/ 12% 88%

0/ 8% 92% /11.5 steps

00.5/ 3% 97%

00/ 0% 100% /13.5 steps

[cowanw]

PS I totally get what you are talking about. The blue in the Zone vi system seems very "actinic". When I run the green light, my time units are a beep every 2 seconds; when I run blue, I get a beep every second and if I accidently run both colours I get 3 beeps to the second. The result tends to an overwhelmingly weighted blue light effect.

[Michael R]

I don’t have that type of head but I agree with the recommendation above to perhaps go for a min/max split exposure approach if you find it difficult to dial in small intermediate adjustments. This will work best with longer exposure times - a feature of the reformulated Ilford papers is that they are faster overall, as well as faster to wavelengths in the violet/blue range (relative to say Ilford Warmtone for example). This is indicated by both the wedge spectrograms and ISO paper speeds particularly under high contrast filtration of tungsten light.

The grade spacing of the new papers is different so typically you need to dial in lower contrast settings (or use a lower Ilford filter number) in comparison with say Ilford MGIV, which Classic replaces. Classic has a similar contrast range as other papers but Cooltone does indeed have a narrower range, not going as low-contrast.

One relatively simple way to get up to approximately an additional “grade” on the low contrast end is to flash the paper. I would suggest this over the use of so-called low contrast print developers as most contemporary enlarging papers really have their sensitometry largely baked in with respect to development characteristics.

[John Layton]

While I've had good luck with Multigrade Classic in general...I do wish it were a bit less sensitive overall.

[Drew Wiley]

Just ignore all the grade talk. It's more contrast versus less. Why complicate the topic? Neither Cooltone nor MG Classic are graded papers anyway; they represent a contrast continuum, and aren't segmented like an arthropod.

If your ZVI light source doesn't give you enough leverage either way, just use maximum "white light", which will probably be actually blue-green (since no red is needed with paper), and apply a supplemental coated glass filter over the lens, either deep blue or deep green. Yes, that amounts to "split printing";
but even that doesn't have to be all or none. You can use just a part of that practical concept to just tweak certain things if needed.

Is your "beeper" adjustable? I don't use a ZVI cold light, but a big high-output Aristo blue-green one, far more powerful than the ZVI, yet with an accessory ZVI compensating timer which beeps, and don't have any of that problem you describe.

Heck, I often print on MGWT and Cooltone during the same session, in the same developer (130). MGWT needs longer exposure time; but otherwise, no real difference in technique which isn't otherwise image-specific.

[Edward Pierce]

The one thing you can do is close your fstop by 1 and then double your time, which will increase your ranges.
My controls are broken in so far as varying the intensity of the blue and green lights. Thus I am required to use split light controls, for example today- 10 time units of green and separately 2 units of blue (about Grade 1 1/2). When I first started I used a graded Stouffer negative to graph grades by time units of each colour. Now I just eyeball the negative and estimate the separate green and blue exposures and then adjust to correct effect. I work between f8 and f11 to allow for enough range for fine tuning of the blue units.
I think the split grade technique here, while perhaps a bigger pain, yields a better understanding and good control; over the issue you have.

Grade/ Blue Green /Stouffer steps (21)

5/ 100% 0% /5.5 steps

4.5/ 80% 20%

4/ 76% 24% /6 steps

3.5/ 52% 48%

3/ 43% 57% /8 steps

2.5/ 35% 65%

2/ 28% 72% /9 steps

1.5/ 22% 78%

1/ 18% 82% /10 steps

0.5/ 12% 88%

0/ 8% 92% /11.5 steps

00.5/ 3% 97%

00/ 0% 100% /13.5 steps

Yes, switching to split printing was my first impulse, and I did a lot of work that way. It’s not really ideal, for me, as I like to burn with intermediate grades. Figuring this out with split printing is double the work, at least.

Thanks for sharing your data. Mine is similar except that with these papers, less blue light is needed with my setup.

I find it helpful when split printing to use a metronome instead of the Z6 compensating timer. With only the blue light, the timer runs much more slowly than with the green light. So with a blue light exposure I was needing to use the tenths of seconds dial, which I don’t like. But doing this misses out on the timer’s compensating action. Everything’s a trade-off I guess.

At first I thought this must be a malfunction. Now I think it’s just the way it was designed; to give consistent exposures to the light gray areas.

[Edward Pierce]

Just ignore all the grade talk. It's more contrast versus less. Why complicate the topic? Neither Cooltone nor MG Classic are graded papers anyway; they represent a contrast continuum, and aren't segmented like an arthropod.

If your ZVI light source doesn't give you enough leverage either way, just use maximum "white light", which will probably be actually blue-green (since no red is needed with paper), and apply a supplemental coated glass filter over the lens, either deep blue or deep green. Yes, that amounts to "split printing";
but even that doesn't have to be all or none. You can use just a part of that practical concept to just tweak certain things if needed.

Is your "beeper" adjustable? I don't use a ZVI cold light, but a big high-output Aristo blue-green one, far more powerful than the ZVI, yet with an accessory ZVI compensating timer which beeps, and don't have any of that problem you describe.

Heck, I often print on MGWT and Cooltone during the same session, in the same developer (130). MGWT needs longer exposure time; but otherwise, no real difference in technique which isn't otherwise image-specific.

I have not tried a filter. Wouldn’t a green filter work better to reduce contrast?

[Drew Wiley]

Yes, the deeper the green, the lower the contrast.

Any compensating timer SHOULD be running slower with blue light because an equivalent amount of blue filtration is generally quite a bit denser than green filtration. But it might take less blue to get the job done, depending on the specific paper. And that is certainly the case with Classic and Cooltone,
if you split print using a deep blue filter to get the highest contrast. But in this case, you're trying to go the opposite direction, to low contrast.

I rarely do true split printing. Mostly I just use the standard light as is, and then if necessary tweak it a little with a supplementary filter over the lens. That's with my 12 X12 VC cold light. I do all my smaller format work (smaller than 8x10 film) using colorheads instead, which are super-easy to work with when it comes to VC papers. But if necessary, I have an 8x10 colorhead too; but its on a big enlarger in bigger room harder to get comfortably heated this time of year.

[cowanw]

I don't think filters are the solutions here. As you know you have a green light and a blue light. You can't increase the amount of blue light your blue light bulb puts out with a filter that removes non blue light (which is what a blue filter does). Similarly a green filter passes the green light your green light bulb makes. A deeper green does not pass more green if the light is green to start with. It does not make green light more green.
There is no white light and this is not a subtractive system. (as I think you know)