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neil poulsen
14-Jun-2010, 12:31
I'm interested in member input regarding the following.

I'm about to do a round of calibrations for 4x5 HP5. Usually, I purchase 25 sheets of Gallerie 8x10 Grade 3 FB paper on which to base these film calibrations. I donít print on this paper, I merely use it for testing. Hereís my logic:

> I use a VC FB paper for printing. If I were to use this paper for testing, the question becomes, at what filter setting do I conduct my testing? (I use a color head for my VC printing.) What filtering gives me a middle ground contrast? In this regard, Gallerie 3 gives me a nice, consistent paper on which to test.

> Iíve heard that Gallerie 3 is actually between a typical grade 2 and grade 3 paper. So, itís a little more snappy than a typical grade 2. Since I like a print thatís kind of snappy, I figure I should do my testing on such a paper.

> I suspect that Ansel Adams didnít expect to be printing a negative for all time on the same paper that he used for calibrating that negative. Papers change.

When I print, I print to taste on VC paper, which will be Ilford VC Warmtone FB.

QUESTION: So, before I start this round of calibrations, does this sound like a reasonable approach, to test on a different paper than that used for printing? Would you change the contrast grade of the testing paper? What suggestions would you offer?

[As background, after testing the ASA for film, (usually half of published ASA), I'll develop a sheet of film at Zone 0. (Pretty much filmbase + fog.) I'll use this sheet to determine the minimum exposure required to achieve maximum black on my testing paper. (Gallerie 3 FB.) Next, I determine the development that gets me a nice Zone 8 and use this as my N development. (I pivot my highlights on Zone 8, vs. Zone 7.) Then, I use the testing paper to create a step tablet and evaluate my N development. I may want to increase or decrease it a little, depending on the results. Once the N development is determined, it's easy enough use a densitometer to determine the other developments, N+1, N-1, etc.]

Donald Miller
14-Jun-2010, 13:03
Why don't you test with the paper that you normally use with a grade two filtration? It seems to me that you are inducing a deliberate error with the method that you use.

Kirk Keyes
14-Jun-2010, 13:19
Neil - you can do a calibration on any paper, but why not just use the paper you intend to use in the end? If you want to compare the Gallery with the WT FB that's fine, but it seems like a lot of extra work.

Use your WT FB with a grade 2 or 3 filter and take it from there.

I'd also use a step wedge to make the exposures and not a Zone 0 sheet, you can get the Zone 0 from the wedge. You can get a full curve of info from the step wedge with one exposure.

Robert Hughes
14-Jun-2010, 13:23
I'm interested in member input regarding the following.

I'm thinking about getting a weed whacker. But I don't want to try it on the weeds in my lawn. How about if I whack some gravel? What size and color stones would be equivalent to my weeds? Or would concrete be better? :confused:

Oren Grad
14-Jun-2010, 13:25
Use the paper you intend to print on, at the filtration you'd like to use as your standard.

Read Phil Davis's "Beyond the Zone System" if you'd like to understand why, or if you want a discussion of calibration that takes full account of paper as well as film characteristics.

John Bowen
14-Jun-2010, 19:03
I've got some Haloid VC paper that should be good for calibration purposes. It expired about 50 years ago, but that shouldn't make any difference....

On a serious note, Don, Kirk and Oren have given you good advice......follow it

Andrew O'Neill
14-Jun-2010, 20:43
Neil,

You really should be testing on the paper that you are actually going to be printing your images on. Are you using contrast filters or do you have a dedicated head? Make step tablets on your VC paper of choice. Measure their reflection densities and then draw curve with data (DR for each filtration). Filter numbers on the bottom of the graph, densities on the vertical axis. This way you can find which filter will give you a "so called" grade 2 contrast. Then you can print your "normal" negatives with this filtration. I've been doing it this way with filters, even with just a blue and green filter for split grade printing, for years. I use a densitometre, but visual inspection of the step wedges (count the number of steps) is just as effective to work out the density range. Afterall, we don't look at prints with a densitometre.

neil poulsen
15-Jun-2010, 05:20
Interesting responses. I should mention that I've always gotten good results with my process, but thought that I would get some input.

I can't use filters in my setup. I'm using a Beseler 45S with a Beseler adapter on my Zone VI enlarger. I could use a Stouffer's step wedge negative and a handheld reflection densitometer that I picked up to select a filtration. Is there a paper-independent definition of what constitutes "Normal" contrast for B&W papers?

Any input on how varying the "Normal" contrast by some amount affects the effectiveness of the zone system that results from the testing?

Once I got away from a condenser enlarger and graded papers and used a Zone VI enlarger and head or my current setup on VC papers, it was anyone's guess what settings would yield a "Normal" grade 2 paper suitable for testing. I felt like I had my feet firmly planted in the clouds. This drove me to select a graded paper for testing. Even with the condenser enlarger, I was using Kodak or Ilford filters with an Agfa VC paper. Again, what's "Normal"?

CG
15-Jun-2010, 11:45
Assuming you believe your basic film processing to be pretty much on target, I'd say the following....

"Normal" paper doesn't matter if you are ordinarily printing on a specific paper. What does matter is what you do use and that's the only thing that matters. If for example, you usually use some oddball paper that is contrasty as heck, and you get best results from it for your purposes, then it should be your standard and you should test to find your normal negative that works well with your chosen paper and outcomes. Why sort out a film processing routine for materials you don't use?

Were you teaching a class for beginners, some middle of the road process would be a good stating point for folks who don't yet have a photographic "personality" - no personal needs and routines to accommodate. But you have found Ilford VC Warmtone FB to suit your needs. Have you the records on filter settings to sort out some middle of the road setting that represents your typical filter pack?

OR

If you are unsure of your basic process, or unhappy with it, and wish to completely restart and recalibrate to a very standard negative, then do tests with a graded paper, grade 2, if you want to get rid of the issue of filter pack entirely, and force your film process back to something close to a plain vanilla negative. I'd ask around here about what grade 2 papers are something like Ilford VC Warmtone FB.

Donald Miller
15-Jun-2010, 13:13
This should give you some idea of where to start should you decide to test using the paper you intend to use for printing.

http://www.ilfordphoto.com/Webfiles/20061302015431815.pdf

cheekygeek
12-Jul-2011, 19:06
I do not yet have a thorough understanding of the Zone System (working on "The Practical Zone System" as it applies to both film and digital) so I hope I'm not thread-jacking or muddying the waters but...

It seems to me that the process is nothing BUT variables. You don't take the manufacturer's ISO rating, but you do take a "standard" developer/time combination to run your initial tests to determine the ISO for your particular equipment/meter. I guess I don't understand why that particular variable gets arbitrarily nailed down.

As you can see, I've never been shy about running my ignorance up a flagpole if the end result will be learning something. :)

Bill Burk
12-Jul-2011, 19:28
Here's a quote from Minor White...

"In photography the testing is done to interlock the variables of camera, enlarger, one's pet brand of film ... and paper, combined with the respective developers, and one's personal processing habits".

One of the main outcomes of doing the testing is learning something.

It's better, scientifically, to isolate variables.

Oren Grad
12-Jul-2011, 19:29
It seems to me that the process is nothing BUT variables. You don't take the manufacturer's ISO rating, but you do take a "standard" developer/time combination to run your initial tests to determine the ISO for your particular equipment/meter. I guess I don't understand why that particular variable gets arbitrarily nailed down.

You have to start somewhere. But there's no reason you have to limit yourself to a single developer/time combination. It's just a matter of how hard you're willing to work, and how comfortable you are keeping different variables straight and assimilating a lot of information at once.

When I first did systematic film testing many years ago - with 35mm TX, as it happens - I shot three identical rolls of film, with each roll having a series of exposure bracket sequences. I developed the three rolls in D-76 1+1 for different times, one as recommended by Kodak, one shorter, and one longer. I printed a bunch of the frames on my then-standard paper. I learned a whole lot in a hurry.

Leigh
12-Jul-2011, 20:35
Usually, I purchase 25 sheets of Gallerie 8x10 Grade 3 FB paper on which to base these film calibrations. I don’t print on this paper, I merely use it for testing.
Forgive the observation, but I think you mis-understand the zone system.

You start with the paper you intend to use, then calibrate it against a step wedge to see how it responds to different negative densities.

Whether it's graded or VC you can do the calibration for different grades. You just have more options (i.e. half steps) with VC than with graded.

Then you work backwards to determine the film exposure and development to produce the negative densities you want.

When you do the calibrations in this order it's really quite a simple system.

- Leigh

jeroldharter
12-Jul-2011, 20:59
Use the paper you intend to print on, at the filtration you'd like to use as your standard.

Read Phil Davis's "Beyond the Zone System" if you'd like to understand why, or if you want a discussion of calibration that takes full account of paper as well as film characteristics.

Ditto.

Bill Burk
12-Jul-2011, 21:01
I think Neil figured it out a while ago, but was trying to see if he should use a fixed grade paper because it is single grade - something rock solid to calibrate to. [I happen to calibrate to graded Galerie because that's my favorite paper].

cheekygeek it sounds like you're just getting started.

As I reconcile the differences in my mind between sensitometry and Zone System, one reason the Zone System messes with the box speed is that you don't use the statistically average 6 2/3 stop subject brightness range at the heart. Zone System arbitrarily made the normal 7 (or 8) whole stops depending what reference guide you follow, so you could use the familiar roman numerals.

So you start out with a test that has wider range than ISO and try to fit it on the same paper from almost black to almost white, you are going to have to underdevelop a bit to get to what you just defined as "normal" into the same places. That is why I think you have to reduce your film speed a little bit.

There's flare included in Zone System tests too, if you do them on camera, so that messes with things too.

Kevin J. Kolosky
12-Jul-2011, 21:29
lots of good answers but some a bit too complicated for guys just starting out.

YOu don't need a step wedge.

What you want to do is pick a paper that you want to print on. And you already know what the range of that paper is. it can't get any whiter than it already is, and it can't get any blacker than black.

So take a blank film and develop it for the recommended time. And then print it for the shortest time it takes to get pure black. Now you have black.

Next, take a film and shoot something black in shade. Place it on zone 1 using the recommended ASA. Develop it for the recommended time. Print it same as the clear film. You want this print to be just a bit lighter than pure black. If not, change the ASA up or down til you get it.

Then, take your film and shoot something white in the sun, using the ASA you found for that Zone 1 negative. process it the same way as the zone 1 neg. If its the exact same as the paper you want to make the neg a bit less dense (let more light through) to get just a faint hint of very very slight gray. If its quite gray you want to make the neg a bit more dense (less light through) to get the print a bit whiter. You do that by changing your developing time.

Now you know what ASA to use and how much to develop for the paper your using to get black, white, and everyting in between.

Bill Burk
12-Jul-2011, 22:06
Minor White described a two-tone target - half sheet of plywood painted medium gray. The other half a full stop darker.

Now shooting that target you test for speed by placing exposures for the two sides on Zone 0 and I at different EI and finding the shot that prints pure black on one side and barely visibly lighter on the lighter side.

You test for developing kind of the same way - you meter and place the exposures of the two sides on Zone VIII and IX and find the development time that makes one side pure white and the other almost white. There's a little more to it but basically it's that simple and no equipment required.

cheekygeek
13-Jul-2011, 00:03
Minor White described a two-tone target - half sheet of plywood painted medium gray. The other half a full stop darker.

I'm off to Sherwin Williams to buy a quart of "Zone V" and "Zone VI". Do I want semi-gloss or matte? :D

tlitody
13-Jul-2011, 01:45
Neil,
I have done testing of this some years ago. The short answer is you test on the paper you will print on. And you use ZERO filtration. i.e. you test it as though it is graded paper. It is really that simple. Then you get your stouffer step wedge and produce a print using zero filtration and then some prints around filtration G2 to find what filtration actually corresponds to the papers natural contrast.
For MGIV FB I found the paper is naturally a G2 and on my enlarger (Durst L1200) the ilford given Y+M figures are spot on. i.e. what ilford say I should be using is correct for my durst. But I know they are not as accurate for all makes of enlarger and filtration which is why you should do the comparative step wedge tests.

Importatntly you should use fresh (new) paper and not older stuff that has been setting around for a few months. It can make a big difference and I have verified this by testing older papers.
The important thing to know is the MGIV FB with zero filtration gives grade 2. I used liquid dektol which is actually polymax developer. (i.e. not the one mixed from powder).

If you do your calibration this way then you will get negatives which you can print easily on both MGIV FB and Galerie.

tlitody
13-Jul-2011, 01:55
Incidentally I found that Galerie G2 gives almost identical contrast curve to MGIV FB with zero filtration. i.e. they are both naturally grade 2 papers when measuring the ISO(R) figures from fresh paper.
The old(several years) MGIV FB paper I tested required above G4 filtration to achieve a G2 ISO(R) value.

tlitody
13-Jul-2011, 02:20
Also regarding your zone system testing, I use a zone 1 negative to ascertain max black print time. This is because you can easily over print max black to be darker than what you really need to give a zone 1 just a hint of tone. If you use a zone 1 neg then you can compare it to a zone 0 neg print to find the correct time where the zone 1 is just showing a hint of tone. If you don't do that you will likely get a zone 1 which is not discernable from a max black.

tlitody
13-Jul-2011, 04:40
What's normal? Can't answer that because it's subjective. Each person has their own normal. But grade 2 to grade 3 is considered normal print contrast for a good quality work print.

Ilford give a ISO(R) value of 100 for grade 2 which is the center of the G2 Range. The range is roughly 95 thru 105 so anything in that range is considered grade 2.

It's quite easy to calculate the range if you have graphed your stouffer step wedge results. The ISO(R) (grade) is the range of exposure between two points on the curve.
The lower point is always where the curve hits 0.04 LogD of your paper density which is a faint highlight value. And the higher point is always the point of the curve where it reaches 90% of the tested paper Dmax. The log range of exposure(not density) between those two points x 100 is the ISO(R) value for the paper or paper/filtration combination. That ISO(R) figure is usually printed on the paper info sheet that comes with Ilford papers at least. So for MGIV if it says its ISO(R) 100 or 105 then its naturally grade 2. i.e. without filtration.

Remember that final print contrast is the result of the combined contrast of the negative and the paper/filter. It is not dependant on just neg contrast or just paper contrast. It is the combining of the two. So using grade 3 as your normal paper doesn't make your final normal print more contrasty if you have calibrated your negative development to it. You could get the same overall contrast using G2 paper but with a slightly more contrasty negative.
However, there is a difference and that is the length of the shoulder and the toe. The higher the final print contrast the shorter the toe and shoulder of the paper and the more abrupt the cutoff. It is that difference which I beleive is why many people prefer to print at grade 3. It gives better shadow and highlight separation than grade 2 paper.
And graded paper gives slightly different toe and shoulder curves which is why many people prefer graded too.

If you want to use G3 for normal then you would need to chart your stouffer step wedges and caluculate which filtration gives around ISO(R) 80 and then calibrate your neg development to that. But if you do that then you will only have a maximum of two extra grades for additional contrast if you ever need it so it's not necessarily a good idea. And not all VC enlargers can reach G5, especially if the paper is not very fresh. Really depends on your filtration. My Durst can do it easily with fresh paper.

grade 00 = ISO(R) 180
grade 0 = ISO(R) 160
grade 1 = ISO(R) 120
grade 2 = ISO(R) 100
grade 3 = ISO(R) 80
grade 4 = ISO(R) 60
grade 5 = ISO(R) 50

the range of exposure between 0.04 and 90% of dmax for grade 2 should be around 1.0Log Exposure. ie. 1*100 = ISO(R)100
or from the grades above you would be looking for an exposure range of 80/100 = 0.8 log Exposure for grade 3 etc.

ic-racer
13-Jul-2011, 07:04
You shouldn't need to alter N development for most cases with a good MG paper that can go from 00 to 5.

Bill Burk
13-Jul-2011, 18:29
I'm off to Sherwin Williams to buy a quart of "Zone V" and "Zone VI". Do I want semi-gloss or matte? :D

I know you're kidding, but just in case you want bragging rights that you did a Zone System test using just one quart of paint... get matte.

This is what I did: I got a quart of the lighter color and asked them to give me a small 2 ounce container of black pigment. I painted the whole board but half would have been fine. Then I added some of the black pigment to the leftover paint until it looked right and painted the other half. When it was dry I metered and then added more black because it wasn't dark enough yet. I think it took three coats but I finally got one-stop difference meter readings.

Bill Burk
13-Jul-2011, 18:36
You shouldn't need to alter N development for most cases with a good MG paper that can go from 00 to 5.

True. But if you have a seriously flat or contrasty scene don't you want to develop a bit longer or use compensating development?

Joe Smigiel
13-Jul-2011, 19:47
I'll join the chorus in recommending the purchase of a step wedge and testing the paper response before trying to calibrate the film exposure and processing. It will save a lot of time and effort seeing the natural response of the paper before juggling film ISO and other aspects of the ZS. You'll have a range of target densities and printed steps on the actual paper you use to judge the later calibrations.

It really simplifies and shortens the entire process and it also eliminates the need to have a transmission densitometer. Depending on which step wedge you purchase (21- or 31-steps) the transmission densities increase by either .10 or .15 for each step (after the clear base which has ~ .05 transmission density). Once you print that wedge you will be able to visually note the densities required to get black, near black, middle grey, threshold white, and paper white. And you will know the target densities associated with those tones on your paper. Then you will have the targets in two forms (density numbers and tones) for your film calibration.

Bill Burk
15-Jul-2011, 17:30
As I reconcile the differences in my mind between sensitometry and Zone System...

...statistically average 6 2/3 stop subject brightness...

...There's flare included in Zone System tests too, if you do them on camera...

A couple corrections called to my attention:

...it's 7 2/3 stop

...camera tests of a painted board are not going to have much flare.

So at least I can correctly say I'm still trying to get my head around the differences between sensitometry and Zone System...

Shen45
15-Jul-2011, 17:56
I never cease to marvel at the comments that BTZS is far to complicated. I can test the paper I use [in my enlarger] and test the film I want in less than a morning using BTZS and be shooting in the afternoon.

I don't suppose anyone here has heard of a horse being designed by a committee? Re read the posts, most have totally complicated a basic single function of photography.

To the OP read Beyond the Zone System by Phil Davis or go to BTZS.org

At least look at both sides of the coin. Either system works well but they are not the same.

Stephen Benskin
16-Jul-2011, 08:51
A couple corrections called to my attention:

...it's 7 2/3 stop

...camera tests of a painted board are not going to have much flare.

So at least I can correctly say I'm still trying to get my head around the differences between sensitometry and Zone System...

Sorry Bill, it's 7 1/3.

Stephen Benskin
16-Jul-2011, 11:42
Bill, your right about the minimal amount of flare in Zone System testing. I've uploaded a example that might help illustrate it.

neil poulsen
17-Jul-2011, 01:42
Forgive the observation, but I think you mis-understand the zone system.

You start with the paper you intend to use, then calibrate it against a step wedge to see how it responds to different negative densities.

Whether it's graded or VC you can do the calibration for different grades. You just have more options (i.e. half steps) with VC than with graded.

Then you work backwards to determine the film exposure and development to produce the negative densities you want.

When you do the calibrations in this order it's really quite a simple system.

- Leigh

I don't misunderstand the zone system. Part of my rationale is that, one can't necessarily expect to print throughout it's lifespan a negative on the same paper. So, where's the harm in testing on a different paper than one might expect to use? As Bill Burk points out, a graded paper gives one something rock solid on which to base calibrations.

But two interesting comments stand out in this thread with respect to the initial question.

One is that Ilford VC paper prints to a grade 2 without any filtration, a detail of which I was unaware. Otherwise, trying to select a filtration on which to base testing makes me feel like I have my feet firmly planted in the clouds. :) I don't like that feeling.

A second, as Kirk suggests, is to use Ilford filters together with my enlarger. Maybe above the negative, together with zero filtration from my 45S head?

tlitody
17-Jul-2011, 05:25
I don't misunderstand the zone system. Part of my rationale is that, one can't necessarily expect to print throughout it's lifespan a negative on the same paper. So, where's the harm in testing on a different paper than one might expect to use? As Bill Burk points out, a graded paper gives one something rock solid on which to base calibrations.

But two interesting comments stand out in this thread with respect to the initial question.

One is that Ilford VC paper prints to a grade 2 without any filtration, a detail of which I was unaware. Otherwise, trying to select a filtration on which to base testing makes me feel like I have my feet firmly planted in the clouds. :) I don't like that feeling.

A second, as Kirk suggests, is to use Ilford filters together with my enlarger. Maybe above the negative, together with zero filtration from my 45S head?

The ilford paper datasheets tell you what the ISO(R) figures are for their papers. Warmtone FB is R110 so its just at the upper limit of G2. But again, this is only for fresh paper as it will lose contrast as time goes by. I keep emphasizing this because I think people have a tendancy to use some old paper lying around for testing purposes and keep their new stuff for printing on.

Stephen Benskin
17-Jul-2011, 08:33
One is that Ilford VC paper prints to a grade 2 without any filtration, a detail of which I was unaware. Otherwise, trying to select a filtration on which to base testing makes me feel like I have my feet firmly planted in the clouds. :) I don't like that feeling.

A second, as Kirk suggests, is to use Ilford filters together with my enlarger. Maybe above the negative, together with zero filtration from my 45S head?

No filtration with multigrade doesn't guarantee a grade 2. It depends on the paper / light source combination. Grades are also somewhat nebulous as manufacturers don't always adhere to the set ranges which is why the ISO paper standard no longer uses grades but ISO R.

The best way to determine what your enlarger is giving you is not to start off with some unknown base but to make a family of curves test. Do six or so tests from filter 0 to filter 5. This way you can nail everything down for your set-up. Then you can work on the film testing.

tlitody
17-Jul-2011, 09:26
No filtration with multigrade doesn't guarantee a grade 2. It depends on the paper / light source combination. Grades are also somewhat nebulous as manufacturers don't always adhere to the set ranges which is why the ISO paper standard no longer uses grades but ISO R.

The best way to determine what your enlarger is giving you is not to start off with some unknown base but to make a family of curves test. Do six or so tests from filter 0 to filter 5. This way you can nail everything down for your set-up. Then you can work on the film testing.

I think this is going way off mark. Sure there will be minor differences from batch to batch of paper but Ilford aim to get R110 with their paper. That puts it at the contrasty end of grade 2 so with any reduction in contrast through ageing it will stay in grade 2 for probably a year or so. To suggest that they are producing their standard papers at some other grade either G3 or G1 is pure nonsense.
I can't speak for other manufactures but in all proabability it will be within half a grade of what they claim which is a very minor adjustment with VC paper. In short this idea of papers not being reliable is just sheep worrying.

Stephen Benskin
17-Jul-2011, 10:48
It's not nonsense. Anyone familiar with Oriental Seagull's Grade 4 can attest to that. A key reason why the ISO standard went with ISOR and no longer uses grades is to minimize the slop factor. The reason manufacturer's still use "grades" is because the concept of grades was too ingrained with photographers. Just like people still say "ASA". VC papers are a different matter though.

I also don't remember saying anything about the age of the paper.

I've worked in labs where all the enlargers produced different LERs even though the enlargers were the same model. You simply can't make assumptions and one assumption that shouldn't be made is that no filter equals a grade two. Testing is always the best approach.

Suggesting doing a family of curves test isn't way off the mark. It's called good testing procedures.

Keep in mind that simply matching the paper's LER to the negative's NDR doesn't guarantee an optimum quality print. In fact, Loyd Jones found that there isn't a perfect system to match film to paper. Jones says that using the negative density "is not a perfect criterion for choosing the paper contrast grade. It's use will lead to first-choice prints in the majority of cases but in many individual cases it will also lead to second-choice prints, and in a few instances to third-choice prints."

He found for negatives with a shorter density range would print better on a paper that is slightly contrastier than would otherwise be indicated by the negative density range and visa versa with a higher than normal negative density ranges. But he concluded that matching is the best of the imperfect systems. Jones, Loyd and Nelson, C.N, The Control of Photographic Printing by Measured Characteristic of the Negative, Journal of the Optical Society of America, vol 32, Oct 1942.

BTW, the family of curves example comes from a program I've written. Not something a sheep does.

I also think you should be more civil with your responses.

Leigh
17-Jul-2011, 22:48
Otherwise, trying to select a filtration on which to base testing makes me feel like I have my feet firmly planted in the clouds.
Neil,

You still don't understand the basic concept.

You test each grade of paper you may wish to use, whether VC or graded.

Then, when confronted with a negative of non-optimal characteristics you know which grade to use to get a proper print. If you've only tested one grade and are confronted with this situation, you're definitely in the clouds, just guessing at best.

This gives you an additional choice for controlling contrast. You can opt to use altered development, or different paper grades, or a combination of the two.

If your filtration system is not totally uniform, you need to change your equipment. I use an Ilford Multigrade 500H additive VC head. You program the paper contrast on the control console, and it's every bit as repeatable as graded papers.

As I've said before, calibration of the paper and printing phase is the first step in setting up the Zone System, not the last.

- Leigh