neil poulsen
3-Mar-2016, 10:08
I've completed calibrations for Ilford HP5 developed in D76 a little differently than I've previously conducted these tests.
Ultimately, whether a conscious decision or not, one makes a choice about the paper contrast that will be used during the calibration process. Testing for film speed, of course, is independent of the choice of paper contrast. However, after the film speed has been found (usually about ASA200 for HP5), I will determine my enlarger and timer settings to print just at maximum black on the paper of choice, and then I will print a number of negative densities at these settings to decide which negative density gives me a Zone VIII that I like. (Some will use Zone VII, or other zones, for this comparison.) Once I know this density, I can establish "N" (normal development), and subsequently, all the remaining developments. (N-1, N+1, N-2, and N+2.)
Examining the choice of paper contrast a little more closely, if one chooses a higher paper contrast, a Zone VIII will not be quite as dense on the negative, and the different developments (N, etc.) won't require as much contrast to achieve that density. So overall, negatives won't be quite as contrasty. (Correct or not, this is the logic from which I'm operating.)
On the other hand, if a paper is chosen with less contrast, one will need to extend the times of the different developments (N, etc.), to achieve the desired Zone VIII density. So overall, negatives will be more contrasty.
To the question that I'm exploring and posing in this thread, which is better? Should one select a paper with less contrast, and thereby end up with higher contrast negatives? Or, should one do the converse and select a higher contrast paper and end up with lower contrast negatives?
As to what's different in my most recent calibrations, in the past, I've picked Ilford Gallery grade 3 contrast paper on which to base my calibrations. Thereafter, all my printing would be on VC papers, usually Ilford warmtone glossy FB. After making this choice, I've typically achieved results that I like quite a lot. (Note also that I used D76 as my developer this time 'round, whereas in the past, I've used Ilford's ID11. My understanding is that ID11 is Ilford's version of Kodak's D76.)
But in a previous thread long ago, LF Forum members admonished me for this, suggesting instead that I should base my calibrations on the paper on which I will print. Fair enough. I now print B&W using a Beseler 45s color head mounted on my enlarger, so I chose Ilford Warmtone glossy FB as my paper printed without any color filtration (neither yellow nor magenta) on the 45s. (I've read that VC papers printed without color filtration is a good approximation of a normal, grade "2" contrast.) In time, I'll see whether I like this choice better, or not.
Let me provide a little explanation regarding previously basing my calibrations on Gallery 3 papers. If one uses a VC paper during calibrations, there's always the question, at what filtration? In this regard, I've always felt like I had my feet firmly planted in the clouds in trying to make this decision. So, I chose a graded paper, and to ease contrast on the negatives, and for shorter development times, I chose grade "3' versus grade "2". Plus, I've read that a Gallery 3 is only about a half-grade higher in contrast than what would be considered "normal," Grade 2 contrast.
Defending a little my previous practice of using a different paper for calibrations than that used for printing, my logic goes as follows. When Ansel Adams conducted his earlier calibrations, he probably had no idea what papers might or might not be still in production years later on which to print earlier negatives. So, why should it matter, as long as he liked the results he was getting? Of course, with years of experience, I assume that he pretty much knew the negative densities he would need for Zone VII or VIII exposures. (I guess this is what I'm still exploring.)
Please note that I don't spend all my time testing. I will use a set of development times for years before next engaging in a new set of calibrations.
So back to the question that's being posed? Which is better: a little higher paper contrast that results in overall lower negative contrast; or, "normal" contrast paper grades that result in higher overall negative contrast?
Ultimately, whether a conscious decision or not, one makes a choice about the paper contrast that will be used during the calibration process. Testing for film speed, of course, is independent of the choice of paper contrast. However, after the film speed has been found (usually about ASA200 for HP5), I will determine my enlarger and timer settings to print just at maximum black on the paper of choice, and then I will print a number of negative densities at these settings to decide which negative density gives me a Zone VIII that I like. (Some will use Zone VII, or other zones, for this comparison.) Once I know this density, I can establish "N" (normal development), and subsequently, all the remaining developments. (N-1, N+1, N-2, and N+2.)
Examining the choice of paper contrast a little more closely, if one chooses a higher paper contrast, a Zone VIII will not be quite as dense on the negative, and the different developments (N, etc.) won't require as much contrast to achieve that density. So overall, negatives won't be quite as contrasty. (Correct or not, this is the logic from which I'm operating.)
On the other hand, if a paper is chosen with less contrast, one will need to extend the times of the different developments (N, etc.), to achieve the desired Zone VIII density. So overall, negatives will be more contrasty.
To the question that I'm exploring and posing in this thread, which is better? Should one select a paper with less contrast, and thereby end up with higher contrast negatives? Or, should one do the converse and select a higher contrast paper and end up with lower contrast negatives?
As to what's different in my most recent calibrations, in the past, I've picked Ilford Gallery grade 3 contrast paper on which to base my calibrations. Thereafter, all my printing would be on VC papers, usually Ilford warmtone glossy FB. After making this choice, I've typically achieved results that I like quite a lot. (Note also that I used D76 as my developer this time 'round, whereas in the past, I've used Ilford's ID11. My understanding is that ID11 is Ilford's version of Kodak's D76.)
But in a previous thread long ago, LF Forum members admonished me for this, suggesting instead that I should base my calibrations on the paper on which I will print. Fair enough. I now print B&W using a Beseler 45s color head mounted on my enlarger, so I chose Ilford Warmtone glossy FB as my paper printed without any color filtration (neither yellow nor magenta) on the 45s. (I've read that VC papers printed without color filtration is a good approximation of a normal, grade "2" contrast.) In time, I'll see whether I like this choice better, or not.
Let me provide a little explanation regarding previously basing my calibrations on Gallery 3 papers. If one uses a VC paper during calibrations, there's always the question, at what filtration? In this regard, I've always felt like I had my feet firmly planted in the clouds in trying to make this decision. So, I chose a graded paper, and to ease contrast on the negatives, and for shorter development times, I chose grade "3' versus grade "2". Plus, I've read that a Gallery 3 is only about a half-grade higher in contrast than what would be considered "normal," Grade 2 contrast.
Defending a little my previous practice of using a different paper for calibrations than that used for printing, my logic goes as follows. When Ansel Adams conducted his earlier calibrations, he probably had no idea what papers might or might not be still in production years later on which to print earlier negatives. So, why should it matter, as long as he liked the results he was getting? Of course, with years of experience, I assume that he pretty much knew the negative densities he would need for Zone VII or VIII exposures. (I guess this is what I'm still exploring.)
Please note that I don't spend all my time testing. I will use a set of development times for years before next engaging in a new set of calibrations.
So back to the question that's being posed? Which is better: a little higher paper contrast that results in overall lower negative contrast; or, "normal" contrast paper grades that result in higher overall negative contrast?