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Old July 17th, 2011, 07:25 PM
Nick Masson Nick Masson is offline
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Default Predicting outcomes when printing with multi-grade paper

Hey all -- another question concerning silver-gelating technology...:

I was wondering how grading of multi-grade paper corresponds to contrast outcome. A few questions, then:
First, if I use a #3 filter on multigrade paper (to make it grade 3, mid-grade), will I get the same results as not using a filter at all?

Secondly, more importantly, as you go up/(down) in grade, will one grade number correspond to one stop of expansion/(contraction)? Is there a distinct correlation?

A hypothetical scenario: let us suppose I print a landscape image where the trees in the foreground are in zone 3, and the clouds zone 5, a two stop difference. If I increase the paper grade by one number (say grade 3 to grade 4), and I print the new image keeping the clouds at zone 5, will the trees be pulled down to zone 2 (a 3 stop difference)? Is the paper emulsion's response linear throughout the different graded papers (or within what range can a linear response be expected?).

I would also be very keen to learn about some of the chemistry behind multi-grade paper (I suspect that it is composed of several different emulsions that have varying responses depending on the incident light. Grade 5 (yellow filter?), would be a high contrast emulsion that is more sensitive to high-intensity light (thus pulling down shadows in the print), than the emulsion for mid-grade...).

Anyway, i've been wondering about many of these specifics for a while and would love to understand them better so I can more accurately anticipate my results. Thanks in advance for any insight!
Cheers,
-Nick
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Old July 19th, 2011, 09:46 AM
Asher Kelman Asher Kelman is offline
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Your question, Nick, deserves attention. Unfortunately, not from my limited knowledge!

Asher
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Old July 19th, 2011, 01:55 PM
Ivan Garcia Ivan Garcia is offline
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Hi Nick.
Multi - grade paper is known for being a nightmare to work with. Albeit, a rewarding one when things do work right. Unfortunately, I do not have much data (translate = experience) with multi - grade paper and therefore, sadly, I can't answer your question. For what is worth, a quick search returned many threads on different forums with one resounding constant... Experiment, take notes... experiment, take notes, experiment...I think you get the idea.
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Old July 19th, 2011, 11:49 PM
Mike Shimwell Mike Shimwell is offline
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Nick

Multigrade paper can actualy be a great help in that you may not need to keep mutiple boxes of graded paper around, as well as giving greater flexibiity.

It can be used, by setting fitration as a graded paper (not sure what pure white does) or can be printed as a split grade paper. DAwid Loubser prints this way - printing at grade 0 filtration for the highlights and grade 5 to get the shadows right. This requires a couple of test strips and he wrote about it in thread somewhere I think.

It works by having a high and low contrast emulsion bended together. Each is sensitive to a different part of the spectrum, hence the abiity to fiter light to achieve different expsoures to each and so vary contrast.

MIke
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Old July 19th, 2011, 11:50 PM
Murray Foote Murray Foote is offline
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Hi Nick

I did use to print on Multigrade in the 80s but not very much. 95% of my printing was Cibachrome and I don't remember enough to answer your questions. I didn't use the multigrade filters, though. I dialled in the filter amounts on my Durst 601 enlarger or my 5x4 colour enlarger or used Beseler sheet filters on an earlier 5x4 condenser enlarger (I don't remember the names of the 5x4 enlargers either).

However, you can find a brief history of Multigrade here and purchase a user manual here. They might answer your questions. Probably someone else will also post who knows more.

With respect to your first question, I would think that without a filter, the paper has less contrast that with any of the filters. This is easy enough to check, though.

p.s. I did use to have a Multigrade handbook. Not sure whether that's the same thing as the user manual linked to above.

Last edited by Murray Foote; July 19th, 2011 at 11:54 PM. Reason: Added afterthought
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Old July 22nd, 2011, 11:45 AM
Nick Masson Nick Masson is offline
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Great, thank you everybody for the input. I suppose I really just need to spend some time in the darkroom and experiment until I develop a good intuitive feel for predicting outcomes given MG paper...
Cheers,
-NICK
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Old July 22nd, 2011, 04:19 PM
Mark Hampton Mark Hampton is offline
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Quote:
Originally Posted by Nick Masson View Post
Great, thank you everybody for the input. I suppose I really just need to spend some time in the darkroom and experiment until I develop a good intuitive feel for predicting outcomes given MG paper...
Cheers,
-NICK
Nick,

Get to ken your film - your development of it - then your print - stage by stage - repeat as close as you can - you will never get the same results time and again - measure - get close - think - measure - change - its not science - there are far to many variables - its a play with chaos - and that's where the beauty in the process is (for me)

enjoy it...
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Old July 23rd, 2011, 01:22 AM
Maris Rusis Maris Rusis is offline
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Quote:
Hey all -- another question concerning silver-gelating technology...:

I was wondering how grading of multi-grade paper corresponds to contrast outcome. A few questions, then:
First, if I use a #3 filter on multigrade paper (to make it grade 3, mid-grade), will I get the same results as not using a filter at all?
Mid-grade is grade #2. Unfiltered paper delivers grade 2 at twice the speed of filtered grade 2.

The key thing with multigrade paper is knowing what changes and what stays the same when contrast filters are changed.

Use test strips to discover the exposure that gives Print Value VIII from the parts of the negative that have Density VIII corresponding to exposure Zone VIII. This stays the same when you change contrast grades. In a nutshell, get the high values right with exposure and jog the dark values up or down by changing contrast filters.

Quote:
Secondly, more importantly, as you go up/(down) in grade, will one grade number correspond to one stop of expansion/(contraction)? Is there a distinct correlation?
Yes, it's a pretty close match between giving N+1 development and going up one contrast grade. N+2 is like a 2 contrast grade increase. Development contractions, N-1 and N-2, work in an opposite manner.

Quote:
A hypothetical scenario: let us suppose I print a landscape image where the trees in the foreground are in zone 3, and the clouds zone 5, a two stop difference. If I increase the paper grade by one number (say grade 3 to grade 4), and I print the new image keeping the clouds at zone 5, will the trees be pulled down to zone 2 (a 3 stop difference)? Is the paper emulsion's response linear throughout the different graded papers (or within what range can a linear response be expected?).
Zone V will go darker if you go up one contrast grade. If you make it light again by reducing exposure Zone III lifts too. So does Zone VIII. It "blows out" to paper base white and the photograph fails. It's Zone VIII that you have to nail and then swing the dark tones around that fixed point. Local controls such as burning and dodging play a part too.
Multigrade emulsion tonal response is approximately linear from one grade to the next for the dark tones, The light tones don't move. Multigrade emulsion speed (light sensitivity) is usually rigged by the manufacturer of the paper and the filters to be constant up to grade 3.5 and half that beyond 3.5.

Unmentioned are a hundred grace-notes and nuances that turn pushing paper in a darkroom into nice art.
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  #9  
Old July 26th, 2011, 05:43 PM
Nick Masson Nick Masson is offline
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Thank you for the detailed response Maris. It seems that the quantitative technique on varying paper grade is analogous to that of exposing negative film (or exactly opposite, since with film you expose for shadows and push/pull your highlight values, whereas here, it seems you expose for your highlights and push/pull shadows). The science makes sense too, seeing as it has to do with emulsion density, which will be reciprocal between negative and print...
Thanks! It makes sense to me on a technical level now as well...
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