Photo Engineer said:
I think it is important to note several things here about Azo paper and about the curves posted by Mr Gainer.
The curves are from 1982, and therefore unless compared directly to the current product may not represent the current curve shape of Azo paper. I don't believe that is the case, but it is best to make note of that.
Second, and most important is the fact that both the current Azo and the older curves show a decided rolloff in the upper shoulder and a dmax of about 2.0 or less. Other characteristic curves of papers posted on the EK web site show dmax values of greater than 2.0. This type of curve, at equivalent grade will give the printer considerably more latitude in the final print. I have already pointed this out but you either don't believe it or don't understand my point.
People keep commenting about how good Azo is, but all I am trying to explain is that some papers out there may be better, and probably are if you give them a try. I find that photographers don't like to change or experiment though. So, you may be overexposing and underdeveloping your Azo paper to get a grade 1.5 print that suits you from a grade 2.0 paper, and complaining that Azo will vanish soon, when you could change to another paper and use a different condition to achieve the same or better results.
After all, it was said above that developer is important. Well, I'm sure that there are combinations out there that will equal or beat Azo if you give them a chance. I'm sure that there is a paper out there that has the same overall tone and curve shape of Azo. It may be an enlarging paper. Only the printer can decide, but unless you try it, you will never know. I put up a curve that might be useful in my original post. It is up to you to try it and see how it looks.
I should also add that you may have been tailoring your negatives to suit your Azo paper. Well, if so, then you are working with less latitude in the negative than you could expect from some other papers. You might have to change your negative exposure as well. We have all adapted as the product mix has changed over the years. The world has not stopped turning and prints by good photographers will still sell.
PE
I am certain that you feel strongly about your position, but I have to disagree with you on some points.
First, I am certainly in agreement that outstanding prints can be made with papers other than AZO, as they can be made with other processes as well, such as albumen, carbon, platinum and palladium, kallitype and so on. Great printers will make great prints, regardless of process.
However, AZO is a silver chloride paper that is quite different from silver bromide papers in many ways. And it is the only paper of its type still made. I actually see the results as another process when compared to silver bromide.
Regarding the curve, I am not saying categorically that it would not be possible to replicate an AZO curve with some other combination of developer/silver bromide paper. However, bear in mind that the standard for AZO is development in amidol so any comparison curves that you present should be based on the amidol standard. Now, I have looked at a lot of curves but I have never seen one for a silver bromide paper that is identical to an AZO curve developed in amidol. The AZO curve in amidol, and limiting ourselves to AZO 2 for this discussion, has a very gentle toe and shoulder that is very different from the toe and shoulder of all silver bromide papers that I have seen. In fact, the AZO 2/amidol curve has more similarities with a Pt./Pd. curve than with a typical silver bromide curve. This fact makes a big difference in the way important highlight and shadow detail is rendered on the print.
Therefore, while it may be possible to change to another film/developer combination and get *better* results by some definition of the concept I don't believe it is possible to get the *same* results, and the plain and simple fact of the matter is that there is an AZO look that many people appear to like, just as there is a Pt./Pd look.
About the curves from modern AZO compared to AZO from the 1980s, I have seen very little difference in my own testing. In fact, I recently did a test comparison of modern AZO #2 and #3 in Ansco 130 (which is also a great developer for AZO) with some well stored paper from 1946, and the curves were for all practical purposes identical, after subtracting the small additional B+F of the old paper.
The maximum reflective density of AZO does appear to be somewhat less than that of a paper such as Polymax fiber FD surface. However, a selenium toned AZO print is capable of Dmax reflective densities as high as log 2.10, and AZO 3 as high as 2.20. More importantly, however, an AZO print is able to use on the print a much higher percentage of total Dmax than papers with more abrupt curves. IDmax is normally figured at 90% of Dmax as the typical value for a silver bromide paper, but the IDmax of AZO, as it is for Pt./Pd. is much closer to 95% of Dmax. In other words, although the maximum reflective Dmax of Polymax, which may be as high as 2.3 or above, is higher than that of AZO 2, the abrupt curve makes it difficult to use all of this reflective density, assuming we still want full shadow detail on the other end of the curve.
Sandy King