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Multigrade vs Galerie: What is grade 3?


Ornello

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Ilford technical reply:
 
On Wednesday, January 26, 2022, 12:26:47 PM EST, technical <technical@harmantechnology.com> wrote:
 
Hi Ornello,
Huge apologies for my delay, but I wanted to properly look at your comments - and discuss all with a colleague who specialises in sensitometry, to make sure we were covering all your points/findings correctly.

We agree with your comments that when using solo colour head filtration – a grade 3 for your enlarger is supposed to be 20M. (I’d quoted the 23Y/56M for your enlarger in the Kodak column using dual colour head filtration. So my values were also still correct. I’d only opted to quote the dual filter values – because it means you don’t have to worry about exposure changes, whereas you would have to with solo filtration).
We also agree that in theory if you had dialled in '0' filters – it should generate a softer contrast/grade 2 filter print.
But we would still never expect you to attain an exact correlation with a specific filter - for different paper products. My guide was 1/2-3/4 grade differences are likely, but it still could be more - and perhaps as per your findings of 1.5 grades different. (That though ought to be very rare).
We've re-looked at our contrast control values for enlargers - and its stil our belief they are correct. They are only meant as guide values.

We've also re-looked at our guide ISO Range (R) values for Galerie Ilfobrom versus MG RC.  We still believe those values shown - are appropriate values. I've attached the charts below - just in case you'd not seen them.  See page 2 for each link.
MGRC – 
https://www.ilfordphoto.com/amfile/file/download/file/1956/product/1701/
Galerie Ilfobrom – https://www.ilfordphoto.com/amfile/file/download/file/1741/product/722/
You'll see that there are slight differences between Galerie Ilfobrom and MGRC Deluxe. But these tables are only a guide. There is no official ISO standard for contrast. But there is an ISO standard/procedure for how to measure contrast - and we follow that for all our products,  and its whats been used to generate any guide  filtration/contrast info. Its how we determine relative contrast between grades of a given product.
Products are not expected to exact match. So for eg variable contrast paper eg MGRC Deluxe - will never have  identical values to an alternate product such as Galerie Ilfobrom at a specific grade. Product formulations have to be/are different - so exact contrast correlation isn't possible.
On top of that - as I mentioned in a prior email, contrast also varies depending if one is comparing an old batch of one product with a new batch of another product. Or it can depend on where a batch fell within limits.
Contrast will vary too - depending on a products capability for eg blacks, tonal range, or even image colour/base tint. All of those can skew how overall contrast looks if comparing eg a grade 2 or 3 Galerie Ilfobrom paper/print - with a eg MGRC Deluxe print at grade 2 or 3.

So though I guided 1/2 to 3/4 grade, occasionally it simply may be more - as you found.

I hope that helps. The key really, is its not our expectation that different products will ever give like-for-like grades, as formulation-wise, its not what we've designed them to be.
I hope you can still find a way that enables you to attain decent grades/the contrast you seek off both products,

 
My reply to this:
 
Thank you for the reply. By the way, I have been doing B&W photography for more than 60 years, so I'm no novice.
 
The problem is establishing a film development regimen in the absence of any 'standard', especially with fixed-grade papers. In the old days, when studio portrait photographers used B&W film and 'portrait' papers such as Ektalure (Kodak) and others from Ansco, AGFA, and DuPont, they simply developed their negatives to print properly in their darkroom, with their enlargers, camera and enlarging lenses. There was therefore no need to vary development times established, unless something changed (such as switching between products because of discontinuations, etc.).
 
Here we have a different situation. I want to be able to print using Galerie paper. It is a superb product. I had not used it for a while, and have been printing only casually using MG IV RC and 25M filtration, which gave satisfactory results. Then I recently tried some of the new MG V RC, using the same filtration. It too was satisfactory. I ordered some Galerie and made some prints from the negatives that had printed nicely with 25M filtration on MG IV and MG V (which is supposed to yield 'grade 3' according to your data). The prints were markedly lower in contrast than they were with the MG at 25 M filtration.
 
Over the weekend I made and developed some new negatives, aiming for a higher contrast negative that would match the Galerie. I succeeded in doing so. Then I made prints using the MG V RC, and found that a filtration of 20 Y made prints that very closely matched the overall contrast of the Galerie prints.
 
Had I not done this testing, I would not have known that my negatives were 'too low' in contrast, if Galerie grade 3 is the reference point. If Galerie should be discontinued, how can anyone determine what density and contrast are best for his negatives? The film development guides are useless for that purpose.
 
The difference between 20 Y and 25 M is quite a lot, and I cannot understand how there can be such a large discrepancy in the data.
 
I have been using Ilford FP4+, Ilford HP5+, Ilford Delta 400, Kodak T-Max 400, Ilford Delta 3200, and Kodak Tri-X.
 
I used to use DuPont Velour Black graded papers back in the 1970s, mostly grade 3 and grade 4, and DuPont Varilour variable-contrast paper with DuPont filters (yellow to magenta). When DuPont papers were discontinued, I switched to Ilford Ilfobrom, which was very satisfactory (although the Ilford matte surface was inferior to DuPont's). It was available in several grades that seemed to match DuPont's closely. This was around 1978.
 
In the interval I obtained different enlarging equipment (Fujimoto enlarger and 50mm Leitz Focotar-2 enlarging lens).
 
So, I have the following questions and concerns:
 
1. Why is Galerie available only in grade 3?
2. Will Ilfospeed grade 3 yield similar contrast to Galerie?
3. Why was 'regular' Ilfobrom discontinued?
4. How can anyone determine the 'proper' negative contrast without a 'reference' paper, since I have learned that my results do not match the data from Ilford?
5. Why doesn't Ilford manufacture a portrait paper?
6. Why doesn't Ilford manufacture a contact-speed paper?
7. How were the filtration data obtained? The difference between 20 Y (from testing) and 25 M (Iford data) is far too great to be acceptable. It was only by virtue of this test that I was able to reveal the discrepancy.
 
Ornello
 
 
 
 
 
 
Edited by Ornello
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When I have used Ilford Multigrade paper in a camera I found that it was about 10 or 20 ISO/ASA.

I wouldn’t be too hard on Ilford, they have given a very complete explanation. There are many variables, negative density, contrast, developer, paper surface etc. Just accept what you are getting and make your own adjustments to get the best out of the paper rather than trying to make it look like multigrade.

Edited by Pyrogallol
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7 hours ago, Pyrogallol said:

When I have used Ilford Multigrade paper in a camera I found that it was about 10 or 20 ISO/ASA.

I wouldn’t be too hard on Ilford, they have given a very complete explanation. There are many variables, negative density, contrast, developer, paper surface etc. Just accept what you are getting and make your own adjustments to get the best out of the paper rather than trying to make it look like multigrade.

It's the other way around: I am trying to make Multigrade look like Galerie, so far as contrast is concerned.

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I may have solved the mystery. The Fujimoto G70 enlarger instructions call for a JCR halogen lamp (150 W, 15 volt). Color temperature is specified as 3100 K.

https://www.lighting.philips.com/main/prof/conventional-lamps-and-tubes/special-lamps/optical-medical-equipment/halogen/halogen-reflector/924793618594_EU/product

The lamp in the lamp-house is an EFP lamp (100 W, 12 volt). Color temperature is specified as 3400 K.

https://www.bulbamerica.com/products/ushio-efp-12v-100w-mr16-reflector-halogen-lamp

I shall order some JCR lamps and try again. If the lamp is supposed to be run on 12 V, and is receiving 15 V, it may well run 'bluer' than spec. Also, the spec for the EFP is 300 K bluer to start with, which would raise the printing contrast. I purchased this unit used, so....

 

Edited by Ornello
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1 hour ago, Ornello said:

I may have solved the mystery. The Fujimoto G70 enlarger instructions call for a JCR halogen lamp (150 W, 15 volt). Color temperature is specified as 3100 K.

https://www.lighting.philips.com/main/prof/conventional-lamps-and-tubes/special-lamps/optical-medical-equipment/halogen/halogen-reflector/924793618594_EU/product

The lamp in the lamp-house is an EFP lamp (100 W, 12 volt). Color temperature is specified as 3400 K.

https://www.bulbamerica.com/products/ushio-efp-12v-100w-mr16-reflector-halogen-lamp

I shall order some JCR lamps and try again. If the lamp is supposed to be run on 12 V, and is receiving 15 V, it may well run 'bluer' than spec. Also, the spec for the EFP is 300 K bluer to start with, which would raise the printing contrast. I purchased this unit used, so....

 

Well, I it seems that isn't right either. The instructions call for 12v 100 watt.

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