I've attached the two test exposures I did to this post. The very dark one is obviously the 30sec exposures and the other is the 1:40 exposures.
As I said, nice sky after 30secs but totally unusable for the foreground.
For me, the correct exposure is somewhere between the second and third exposures so between 3:20 and 5 mins but closer to 5 mins. If 6:20 was what I measured for EI 3 then I guesstimated say a half a stop less exposure and came up with an EI of 4 for the paper.
I took another shot this evening and, as another experiment, used the developer I had mixed yesterday and had dev'd 4 prints in. I had mixed up 30ml dev + 450ml water. I know the Harman paper likes good dev, so I wanted to see how fresh.....turns out I can't use the day before's dev. The print was pretty grey although on the plus side the exposure seemed pretty good.
Joe, thanks for that.....any particular soup?
Well, I've been using Ilford's PQ liquid concentrate, mixed 1+15, and I only use it for the Harman paper the same day it's mixed, but do save the used mixture for several weeks time for use with paper negatives (I like grade 2 RC glossy for negatives).
My choice of developer was not in any way scientific, it's just what the local camera store keeps in stock. I had purchased a large jug of Ilford Universal paper developer a year or so ago and it didn't last more than half the jug before it went south; I must not shoot enough to warrant the large containers, so I try to purchase smaller containers and use them up before replacement.
My experience with both developers and the Harman paper is almost identical, so I don't think choice of developer is that crucial, only that you mix it fresh, in the appropriate dilution, at a consistent temperature to get repeatable results. The Harman paper has a narrow sweet spot in the various process parameters, so you have to take care to use consistent working habits.
PS: Just to add that I don't favor powdered developers because the stock solution has a relatively short shelf life as compared to small containers of liquid concentrate, despite the cheaper cost of the powder. And it's not a good habit to try mixing smaller quantities of powder into stock solutions because the various components in the powder are not uniformly mixed. Unless you make your own home-brewed powdered developers, but that's another story.
PPS: You're on the right track with your tests, but I would advise not to try exposing to retain detail in the sky (unless the sky itself is the primary subject matter). Just let the sky get blown out to white and concentrate on exposing so the principle objects in the landscape are properly exposed. If you do this, you might find the proper exposure index for the Harman paper is slower than ISO 4, based on my experience. Landscapes in 19th century photography typically had blown out skies for the reason that their emulsions had similar blue-sensitivity as contemporary papers like the Harman.
Last edited by Joe VanCleave; 02-20-2012 at 08:59 PM. Click to view previous post history.
Actually Joe, I meant which brand of soup for the preflashing unit
Nonetheless you have given me some fantastic advice. I used to have a darkroom about 7 years ago but it had to be packed away to storage when we moved and I had moved over to digital. I got the analogue bug a few weeks ago again and went back to storage to retrieve my stuff only to find my dad had had a clear out and given it all away! So I'm running pretty basic at the moment; a pinhole camera and three trays! But that's part of the fun!
I think I'll have to experiment in the darkroom with the chems. It feels like a waste mixing up 30ml of dev for just a couple of prints, I might try mixing 15mls + water next time, see how that lasts, see if I can get 6 prints out of it.
All of this is a step toward getting a nice 5x4 monorail (or a crappy one, I'm on a pretty tight budget). I've only ever shot 35mm and a little 120. I like the idea of slowing down and thinking again.
Thanks again for all your help.