Please excuse the long post. If you can take the time to read it and help diagnose my frustration that would help me, and might also help others who experience similar frustration.
I have been Pt Pd printing for a little less than a year. I had some beginner's luck, but it seems the more I learn, the less I know. The more prints I make, the harder it's getting. I'll start with a few observations of my experiences and then talk about the problems that caused me to post this.
My first negs and first successes were with negs shot on HP5 and developed in D76 1:1. They were exposed at EI 250 and developed in rotary tubes (Beseler on a Unicolor base). The negs look a little dense to the eye, the highlights are a little blocked. On silver, this negs prints well on grade 3 to 3.5 VC. It requires a lot of burning on some of the highlight areas. In PtPd, using the NA2 method, it printed well with a coating of 18 drops FO, 15 drops Pd, and 3 drops 20% NA2. I didn't realize in those days that the NA2 should be in addition to the total drop count, and thought that it should take the place of an equal number of drops of Pd. The exposure time was about 20 minutes.
I continued more or less in this vein until I got frustrated with extra edge density due to the agitation patterns of the Beseler tubes. During this time I shot a lot of Ilford and TMY, and saw drop counts of more or less 18/15/3 to 18/12/6 to get prints that had satisfactory contrast. I've been told this is too much NA2 and that I should work to get contrastier negatives, so I started working on that by increasing development.
I switched to JOBO Expert drum. I also started using Pyrocat HD.
I re-read more carefully the Weese text "New Platinum Print" and the Arentz text, and realized that my drop count was in error. I needed to ADD the NA2 count to the total drops, not replace. I corresponded with Carl Weese and he suggested that I had gone down the rabbit hole in terms of chasing contrast with NA2, leading to longer and longer exposure times. I dialed back the NA2 and saw slight reduction in print times, but with a less than acceptable contrast scale.
My exposure times ARE quite a bit longer than my colleagues with the same equipment. Where they have 6 to 8 minutes exposures on average (with the same film, developer, exposure unit), I have times ranging from 18-35 minutes.
In an attempt to correct this, I looked critically at all the negs. I don't have a densitometer. My thinking was that, maybe these very dense negs were a result of overexposure AND overdevelopment. I was overdeveloping to get the DR I needed for the PtPd process, but maybe my old technique of overexposing a bit (like rating HP5 at 250 for better shadow detail) from my Silver printing habits, was resulting in too much density. I began to experiment with higher EI, rating the my most recent film (J&C Classic 400) at 400.
In these recent test, I got D76 1:1 negs that required 15 minutes UV exposure to get a decent black in the B+F area. This 15 minute exposure resulted in prints that were too dark in the Subject area. So, negs too thin. I also tried Pyrocat, and these same negs required 20+ minutes for a good black in B+F area and again resulted in a too dark print. I increased development in an effort to expand the DR. This morning I have pulled an 'acceptable' print with these parameters: J&C Classic 400 negative exposed at EI400, developed in Pyrocat 2:2:100 for 19 minutes at 72 degrees in Expert Drum on Unicolor base. Perceptions of negative--looks a little dense for Silver, but easily printable, no blocked highlights except for specular reflections. Coating was 20/20/2 drops 20% NA2, (which corresponds to Arentz 5s, the MIDDLE grade). To get an acceptable print took 37 minutes, and the B+F area is still not quite as black as areas of the print where there is PtPd coating that had no negative blocking them. Here, there's a very dense black, but in the B+F it's just near black. If I had gone for black in the B+F area, the subject would have been too dark. The print has very good contrast.
I'm eager to resolve the issue and think I will buy a Stouffer 21 step wedge to try to get some uniformity to the tests.
I am confused why friends with the same expo unit--a total of 8, 18-inch BLB tubes, positioned 5 inches above the contact frame--would have such wildly different times to get a respectable black in the B+F area.
Does J&C Classic 400 have more B+F than HP5? Than TMY?
I've never done film testing, because for my needs to date, I've been able to get close enough for Silver printing. Do I really need to pick a film and do the testing? Do I need a densitometer?
Thanks for any thought you give this and any response.
Neal
I have been Pt Pd printing for a little less than a year. I had some beginner's luck, but it seems the more I learn, the less I know. The more prints I make, the harder it's getting. I'll start with a few observations of my experiences and then talk about the problems that caused me to post this.
My first negs and first successes were with negs shot on HP5 and developed in D76 1:1. They were exposed at EI 250 and developed in rotary tubes (Beseler on a Unicolor base). The negs look a little dense to the eye, the highlights are a little blocked. On silver, this negs prints well on grade 3 to 3.5 VC. It requires a lot of burning on some of the highlight areas. In PtPd, using the NA2 method, it printed well with a coating of 18 drops FO, 15 drops Pd, and 3 drops 20% NA2. I didn't realize in those days that the NA2 should be in addition to the total drop count, and thought that it should take the place of an equal number of drops of Pd. The exposure time was about 20 minutes.
I continued more or less in this vein until I got frustrated with extra edge density due to the agitation patterns of the Beseler tubes. During this time I shot a lot of Ilford and TMY, and saw drop counts of more or less 18/15/3 to 18/12/6 to get prints that had satisfactory contrast. I've been told this is too much NA2 and that I should work to get contrastier negatives, so I started working on that by increasing development.
I switched to JOBO Expert drum. I also started using Pyrocat HD.
I re-read more carefully the Weese text "New Platinum Print" and the Arentz text, and realized that my drop count was in error. I needed to ADD the NA2 count to the total drops, not replace. I corresponded with Carl Weese and he suggested that I had gone down the rabbit hole in terms of chasing contrast with NA2, leading to longer and longer exposure times. I dialed back the NA2 and saw slight reduction in print times, but with a less than acceptable contrast scale.
My exposure times ARE quite a bit longer than my colleagues with the same equipment. Where they have 6 to 8 minutes exposures on average (with the same film, developer, exposure unit), I have times ranging from 18-35 minutes.
In an attempt to correct this, I looked critically at all the negs. I don't have a densitometer. My thinking was that, maybe these very dense negs were a result of overexposure AND overdevelopment. I was overdeveloping to get the DR I needed for the PtPd process, but maybe my old technique of overexposing a bit (like rating HP5 at 250 for better shadow detail) from my Silver printing habits, was resulting in too much density. I began to experiment with higher EI, rating the my most recent film (J&C Classic 400) at 400.
In these recent test, I got D76 1:1 negs that required 15 minutes UV exposure to get a decent black in the B+F area. This 15 minute exposure resulted in prints that were too dark in the Subject area. So, negs too thin. I also tried Pyrocat, and these same negs required 20+ minutes for a good black in B+F area and again resulted in a too dark print. I increased development in an effort to expand the DR. This morning I have pulled an 'acceptable' print with these parameters: J&C Classic 400 negative exposed at EI400, developed in Pyrocat 2:2:100 for 19 minutes at 72 degrees in Expert Drum on Unicolor base. Perceptions of negative--looks a little dense for Silver, but easily printable, no blocked highlights except for specular reflections. Coating was 20/20/2 drops 20% NA2, (which corresponds to Arentz 5s, the MIDDLE grade). To get an acceptable print took 37 minutes, and the B+F area is still not quite as black as areas of the print where there is PtPd coating that had no negative blocking them. Here, there's a very dense black, but in the B+F it's just near black. If I had gone for black in the B+F area, the subject would have been too dark. The print has very good contrast.
I'm eager to resolve the issue and think I will buy a Stouffer 21 step wedge to try to get some uniformity to the tests.
I am confused why friends with the same expo unit--a total of 8, 18-inch BLB tubes, positioned 5 inches above the contact frame--would have such wildly different times to get a respectable black in the B+F area.
Does J&C Classic 400 have more B+F than HP5? Than TMY?
I've never done film testing, because for my needs to date, I've been able to get close enough for Silver printing. Do I really need to pick a film and do the testing? Do I need a densitometer?
Thanks for any thought you give this and any response.
Neal
I'll try printing it tomorrow which should tell me how much to adjust my dev next time round.
