If I may be excused to open up a little the topic of the thread, I'd like to have some comments on the meaning of paper/neg matching.
What I understand so far from readings and experience is that there is a rather simple correlation between the overall contrast of a negative (i.e. with the grade of a paper. If the density range of a negative is high (from very thin to very thick), then you are likely to need a lower grade of paper, and vice versa.
Now let's say we're comparing two different papers, A and B, of the same grade. What are the aspects of their curve that makes them different?
Mhv,
Contrast changes.
You have the idea of matching the overall contrast of your film to the contrast of your paper.
You describe one way this issue comes up--taking a negative and then adjusting the contrast of the paper to match your negative. I do this every time I print on VC paper. I do test strips focusing on the highlights to set the exposure. I then adjust the contrast up or down to set the shadows properly.
The issue of overall contrast changes also comes up in that a photographer will decide on a grade of paper on which to print. Say you choose grade 2 as your standard paper grade. By experience or testing, you can adjust your standard development time to make the majority of your negs print well on that paper, with only minor changes to the contrast of the paper when enlarging.
Matching film and paper tonal gradation.
Matching the contrast of the negative to the paper contrast is only the beginning of making exceptional prints. It also helps to match the way paper distributes the tones between the extremes with the way the film distributes the tones. You can have a perfectly developed negative and print that on two different papers at the same contrast. One will look okay and the other will sparkle. There has to be more than global contrast changes going on. Simply, a given film will match up with one paper better than with another. Thats why I always take paper recommendations with a grain of salt. To me it is a film and paper combination that is important. Just focusing on half the equation doesnt really tell us much.
Phil Davis describes this his book, BTZS, in chapter 10 Image Gradation. He states:
When we fail to get good results it may be that weve handled the materials poorly, but it also may be because weve chosen the wrong set of materials for the subject type and for the interpretation we had in mind. Our materials may have unique characteristics but they work in concert. Although each exerts its individual influence, the ultimate look of the print image results from their combined effect. p. 147.
Some combinations of materials can make this relatively easy; others may make it very difficult indeed. p, 147.
He then goes on and describes the effect on the final image from a short toe v. long toe film and the corresponding paper choice. If you really want to delve into the science of sensitometry, read Phils book or visit the BTZS web site. As I stated above, I cant look at a film or paper curve and envision how it will print. So I have to physically print my negs on different papers and compare the results.
If you dont want to go into the whole film testing/paper testing mode, you can always just try different papers with your negs. Take a well exposed and developed negative and print it at the same contrast on different papers. (Note, you need to visually make sure that the papers are the same contrast. Two papers printed with the same filter may print at different grades). Compare the highlight separation and the rendering of the shadows. Pick the best one for your basic paper.
If you have trouble printing on one paper, it may be that you dont have a good match between that paper and your film/developer choice. Try another paper.
Personally, I like a KISS approach. One basic film, one high speed film, one film developer, one warm tone paper and one neutral tone paper. Getting everything to line up is the problem.