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More Analyser Pro Calibration Weirdness...Densitometer Edition

removedacct3

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I don't suppose anyone knows but should I adjust my offsets with the ND filter in place, or will the meter simply be able to compensate? Apologies if that's a dumb question.

No, you don't. The ND filter is only needed to make the exposure time for test stripes more managable. That's all there is to that. I do not have the Zonemaster Calibration manual at hand, but I believe that the use of a ND filter is mentioned as a method of lowering light output when exposure times become too short.
 

mmerig

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MrclSchprs is correct -- see page 5 of the Calibration manual where it recommends using a ND filter (I used film exposed to a gray card) to get the times long enough to get manageable, precise results.
 

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If you don't have or don't want to use a ND filter it's may be easier to modify the offset value before making your tests: -12 for minus 1 stop, -24 for minus 2 stops and so on. That's the way I used. With a Heiland LED VC Head I start with -48 (minus 4 stops). You can even go to half stop.
 
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Well I think the ND will need to stay on. If I'm getting exposure times of under 10 seconds with your average negative it would be increasingly hard to do any dodge and burn work. Now I'm just a little worried about the fact that I've been metering at 00 instead of white light. But I'm pretty resistant to going through the calibration procedures again. The last thing I need to do is nail down some errant contrast settings and then I'd like to start actually printing...
 

removedacct3

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Now I'm just a little worried about the fact that I've been metering at 00 instead of white light.

Metering at 00? If it works for you, it works for you! But the whole RH Designs metering method is designed around unfiltered, grade 2, white light.

I am about to order a new-to-me paper. Foma MG Classic 133. I will be ordering from Foma's own webshop and hopefully the paper arrives before the weekend. That way I will be able to calibrate my ZMII for this paper / developer combi. And unlike you, and this is in no way meant as a funny pun, I am really looking forward to execute the calibration procedure. Once I have the numbers of this paper / developer combi (I am using Moersch 4812 developer) I will show you the numbers.

Regarding the ND filter. I bought a high quality ND filter just for my enlarger lenses for that single reason ... to have time for dodging and burning.
 

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Regarding the ND filter. I bought a high quality ND filter just for my enlarger lenses for that single reason ... to have time for dodging and burning.
Same here. Bought two, actually, as I have lenses with two different filter sizes. I wind up using it more than I'd have expected, and probably wouldn't be able to easily do color printing without it. (Okay, I know you can fake it with dichroic adjustments, but I'd rather not jumble too many variable together.)
 
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I think I got it going! I did have to re do the offsets for metering on the “focus” light. But the numbers all seem to make sense and the prints look right. Now it’ll be just about figuring out the workflow. It’s not so easy to always pick the right shadow target. I am enjoying the zone placement aspect though.

If I wanted to split print does anyone use the Analyser for that purpose?

 

dkonigs

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So I actually spent most of today going through the exposure calibration process myself. I wanted to build a profile for the Ilford MG V RC paper with the Moersch Eco 4812 developer, for both the Ilford under-the-lens filters and the dichroic adjustments in my enlarger head. Needless to say, it took a lot of test strips (did the last time I went through this as well), but that part is finally finished. Its the second time I've gone through this routine, so at least I knew what I was doing. (And I've recently gotten a brand-new calibration plaque for my 810TR densitometer, so hopefully my numbers are good. Kinda makes me want to re-measure the test strips from my last run through this process, in case my older profiles also need tweaking.)

Of course the one thing I haven't done yet is contrast calibration. That's on my to-do list for tomorrow. Of course actually figuring out the exposure to use for the contrast test strips is something not so clearly explained in the instructions. Maybe I'll just have to fiddle a lot to get my starting point, then hope it doesn't change much as I test the different grades.
 

removedacct3

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Of course actually figuring out the exposure to use for the contrast test strips is something not so clearly explained in the instructions.

The exposure time for contrast calibration is not very critical. Just make one or two test strips of the calibration step wedge and make sure you have all the tones between pitch black and pure white. Once you found that time, you can use it for all grades.
 
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Ok, drum roll please....

Here is the calibration data!

Ilford Multigrade Classic Glossy - Ansco 130 1:2 75˚F - Heiland LED Cold Light
00 -35 // 0 -35 // 1 -38 // 2 -38 // 3 -40 // 4 -55 // 5 -66
195 - 150 - 105 - 90 - 80 - 60 - 60
 

dkonigs

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So I spent all morning making contrast step wedge strips, all afternoon compiling densitometer readings, and the rest of the day fiddling with all the numbers in a spreadsheet and stats software.
When all was said and done, I actually ended up with numbers for grades 00 through 4 that were very close to the ones in Ilford's official datasheets. So I think I did it right.

However, my grade 5 number was very close to my grade 4 number, and a little farther from Ilford's datasheet value. (though I'll admit the two are fairly close in the datasheet as well). What's also interesting is that my grade 5 filter gave me basically the same contrast as 170M in my dichroic head (spec says grade 5 is 199M, but my head only goes up to 170M). So maybe my (new, but no idea how long it sat on the shelf) grade 5 filter is a smidge faded?
Regardless, I don't think I've ever printed at grade 5, so I'm not terribly worried. Actually, I think its rare I ever want to go past grade 3.

P.S. I've been doing all this to calibrate my meter for processing MG V RC paper /w Moersch Eco 4812 developer
 
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I use the Stop Clock on my MG 500 / De Vere 504 set-up. Not sure I'd get on with analysers... My 5108 just has a basic timer and I approximate settings in my head before exposure.

I'm going to try using the analyser for a while, but I could see swapping it for a stop clock in the future. I'm noticing that I'm sort of letting the analyser do the thinking for me, which is not always great in terms of creative printing. It's also not the easiest timer for split grade, though I may be just missing some functionality that it has. To me the 'promise' is that you could realistically stop making test strips. I'm just not sure if I'll ever get there... Though it does probably reduce the number of them.
 

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Just in case anyone here is interested in my own numbers from all this fiddling, I've attached a copy of my latest calibration results table:
(Kinda wish there was a better place to share this stuff, besides random forum posts.)
 

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Last weekend I had the pleasure of calibrating a new-to-me paper: Foma MG Classic 133. It's called a velvet surface, it has some shine but not as much as a gloss paper. These are my results. The grade 5 contrast number can not be any good. But even ignoring that number, I think the resuits are quite surprising. For the sake of consistency I've re-recalibrated my new stock of Fomabrom 122. Those numbers do not surprise me at all. It's the contrast value of MG Classic 133 that are surprising. I will double check my densitometer (Agfa Gevaert D-102) with a calibrated Stouffer reflective step wedge. But of course, the proof of the pudding is in the eating, I will need to do some regular prints to see what I get out of it.

 

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To follow up my own post.

Today I printed a new grade 5 calibration print. This time I double checked the grade I was using ... grade 5. I also checked my densitometer using a calibrated reflective Stouffer wedge. The low numbers were still good, the high numbers needed a little adjustment. Nothing major though. That print is drying as I type. I will meter it tomorrow.

And I also printed a single portrait on various papers. I metered only once, printed on Fomabrom 112, switched paper channel, adjusted the exposure and contrast to, more or less, the same range and printed on MG Classic 133. Prints are drying now. Fomabrom 112 was printed using grade 2 and MG Classic was printed using grade 4.7! Quite a difference, don't you think? It is however, more or less, a confirmation of the calibration numbers of my previous post.
 
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That is a big and surprising difference. It just goes to show the absolute necessity of calibration with this device. Not only that, but you really need to have a clear 'pre-visualization' of your highlight and shadow targets.
 

removedacct3

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I've retested grade 5 for Foma MG Classic 133 and measured its contrast range. See the image below. Still a huge contrast range when compared with, for example, Fomabrom 122.