RH Designs Analyzer settings for Maco Multibrom F paper

goros

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Helo all,

I'm going to try another paper, Efke Varicon VC Fb, basically the same than Maco Multibrom F paper. I use a RH Design Analyzer and must calibrate it for this new paper.

Does anyone have the settings for this paper and want to share them?

Thanks in advance
 

GeorgesGiralt

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Hi Alfonso !
To get started, you've to find the data sheet for the paper you will use.
Look at the speed and do a comparison with the Ilford MGIV which is standard in the analyser.
Insert te speed difference between the new paper and this MGIV converted to fraction of stops (1/12th if I remeber corectly).
Next, find the ISO-R values for the new paper and enter them into the contrast values for the channel you are calibrating.
Et voila !
You'll have quite good starting points, IF you use under the lens Ilford filters for contrast control because the Analyser is calibrated for this kind of filter set.
Next, you will only have to refine the settings if you're not totally satisfied when printing.
Hope this helps.
 
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goros

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Hi Georges,

Thanks a lot for the reply. I have found a table that shows, for each grade, the ISO Speed and ISO Range. It is something like this:

Grade Filter ISO-Speed ISO-Range
0 0 P 50-64 R 150
1 1 P 90-100 R 120

etc.

According Ilford MG IV FB datasheet:

Grade Filter ISO-Speed ISO-Range
00 00 P 200 R 170
0 0 P 200 R 150
1 1 P 200 R 130 (this paper has a paper ISO speed of 200 up to Grade 3 and then ISO 100)

etc.

What do I have to convert to fraction of stops?

Well, I will look the manual and try to gess it.

Thanks again
 

GeorgesGiralt

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for grade 00 the paper is 50 speed and MGIV is 200 speed. 50 is 1/4 of 200 So there are 2 stops from 50 to 200. So you've to enter, IIRC, 24 steps into the exposure correction. With a plus sign as the new paper is less sensitive than the Ilford.
For that grade you will next enter 150 for thecontrast value.
And so on.
 
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goros

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I think the text in my previous message has shifted to the left.

The first line of data for the Multibrom paper are for Grade 0, not for Grade 00 as in the Ilford paper. This means that there is no data for Grade 00 for the Multibrom paper.

What does IIRC mean?

And the Plus sign, where do I have to input that?

Sorry for the amount of questions but I don't have the instructions manual with me. I'm sure everything would be much more clear if I had it here.

Again Georges, thanks
 

RH Designs

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goros said:
Sorry for the amount of questions but I don't have the instructions manual with me. I'm sure everything would be much more clear if I had it here.
Click to expand...

Hi Alfonso

You can download the manual from our website here

Georges is exactly right about how to interpret the ISO(P) and ISO(R) figures - work out the difference in stops between the Ilford ISO(P) and that of your paper at each grade, and enter those figures in the exposure correction table in your Analyser. As your paper has a lower ISO(P) figure it means that it is slower, so more exposure is needed - in this case increase the exposure correction by the difference using the up arrow key.

A sequence of ISO(P) figures would be
50, 64, 80, 100, 125, 150, 200 etc
(just like the film speed setting on your camera)
Each of these figures is a change of a third of a stop, which is 4 units of correction on your Analyser. At grade 1 for example, Ilford is 200 ISO(P) and your paper is 100 - difference three thirds of a stop, or 12 units of correction.

The ISO(R) contrast figures are entered directly so for example at grade 1, the Ilford paper has an ISO(R) of 130 and your paper is 120, so just reduce the existing 130 figure to 120 using the down arrow key.

Hope that helps!
 
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goros

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Reading the Analyzer instructions I saw that the reference paper settings are for a difusser enlarger. I have a Kaiser condenser enlarger, so I have to calibrate the Analyzer for the papers I'm using.

What would the right procedure be? Calibrate for Ilford MG IV RC as reference paper again and correct the ISO-P or do it individually for each paper?

Thanks in advance
 

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Best to do each paper individually. That way you take into account every variable (and there are many!).
 

GeorgesGiralt

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Alfonso,
My enlarger is a Durst Laborator 1000 with condensers.
When I go for a new paper, I enter the data from the spec sheets as explained above.
And it's pretty close to the correct values (I use under the lens filters as does Richard when calibration the Analyser).
So you may get started just entering the theoretical values...
BTW, IIRC means If I Recall Corectly ;-)
 
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goros

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Last question...I hope

Well, so far, this is the last question I have:

If the new paper speed is, let's say, 125 and the reference paper speed is 200, the correction figure to input is 2 1/3 steps by 4 equals 8. This 8 is a negative or a positive value?

Thanks again and again and ...
 

mikeg

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goros said:
Reading the Analyzer instructions I saw that the reference paper settings are for a difusser enlarger. I have a Kaiser condenser enlarger, so I have to calibrate the Analyzer for the papers I'm using.
Click to expand...

I've got a Kaiser enlarger and I find the default values in the Analyser Pro to be correct for Ilford MGIV RC. Try the default settings with a negative that you know well. Make sure that it is well exposed and has a full range of tones. Compare the results you get with the analyser with your old prints.

I did this with one of my favourite negatives when I first got the analyser and found that the analyser recommended printing half a grade harder which produced an even better print!

Mike
 

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It's a positive value because the new paper speed is a smaller number than the reference, indicating that the new paper is slower and therefore requires more exposure.
 
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