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View Full Version : Decrease exposure, increase dilution or decrease development.



drgoose
24-Apr-2016, 14:26
So I was shooting Fuji HR X ray film at EI of 50 and developing it on trays using PMK pyro 1+2+100 for 7 minutes and ending up with scratch negatives but with good density. I recently acquired some tanks and hangers and because PMK pyro oxidizes in minutes it would be really expensive to make 15 liters every time I want to develop a couple of sheets of film so I decided to give Dektol a try. I dove into the thread from Hell (only 400 and some pages of X ray thread) and found some people using Dektol 1:10 for 6 minutes so I decided to give it a go. I exposed my sheet again at EI 50 and then developed it in the tank one sheet for 5 minutes and one for 8. I ended up with one bullet proof negative and one kryptonite proof negative so my question is what is the next logical step?

-Decrease my EI to 100 or 200
-Increase my Dektol dilution to 1:20
-I really don't want to decrease my time to less than 5 minutes.

All help appreciated and I hope this thing does not get appended to the X ray thread from hell.

Thanks

Joaquin.

mdarnton
24-Apr-2016, 14:43
I have seen people using Dektol in the x-ray thread, but I have a hard time understanding why someone would use a high-energy, high-contrast developer with a high contrast film and expect normal negatives. Your results seem to confirm that, so I would dilute my Dektol to 0:20 and find a developer more suited to the problem. I have the same feeling, but less, about Rodinal, which appears to me, simply based on the results I see all over the net, to be a developer that's poor at developing shadow detail and good at blowing highlights, but people swear by it, so go figure--maybe it's the cheap talking--I won't dig into that one. :-)

drgoose
24-Apr-2016, 14:46
What would you suggest as a good developer to try that would have a good shelf life in tanks with floating lids?

mdarnton
24-Apr-2016, 15:34
I do use tanks and hangers. I used D23 for a while, diluted 1:7. I understand (from the AA's mentioned further on) that it can't possibly last more than a couple of hours in that type of situation and you have to throw it right away, because supposed oxidation will kill it dead immediately, but mine was consistently lasting at least 4-5 months, at which point I would throw it away if I hadn't run enough film through it to kill it, since I was going through long periods when I didn't shoot at all. But that dilution was so weak that it wouldn't do many sheets, and I wasn't replenishing it, so sometimes the times were getting longer and longer . . . and finally in one busy phase it just quit. Fortunately, it's very easy to whip up a batch on the spot under the safe light. :-)

Anyway, I guess I could have replenished it, but I always end up falling out of love with D23 for the same reason--lack of highlight sparkle--so I ditched it last winter for D76.

Now I'm shooting more often and using D76, diluted 1:1, replenishing it according to the directions: about 3/4 ounce of replenisher per 8x10 sheet. That, also, is supposed to be a one-shot with dire warnings to not re-use it, but I think, frankly, that a lot of photo advice comes from Armchair Admirals who never try the things they don't want you to do. The dilute D76 been going four months now in my tanks, with no sign of failure. I'm not quite happy yet, and am thinking of messing with the recipe a bit to get it to do what I want, maybe bridging the distance between D23 and D76. Someone in the Big Thread recommended that approach, but I thought I'd get familiar with the D76/x-ray combo first.

I develop by inspection, so I can keep track not only of how things look, but meter how the developer is doing over time and adjust things accordingly. Even if you don't have confidence in your inspection skills now, the only way you will get them is by getting a good light and watching what's happening while you use the clock. That will give you good information on how it works, and inform you on how you can make changes to what you do. In your present case, you might have started wondering if your film really should be getting THAT dark. :-) FYI, when I inspect, I'm waiting for the shadows and shadow separation that I know should be there to show up, mostly not looking at the rest except to worry that it's going too far, and where are my shadows!!??, if that's helpful. With double-layer x-ray film you can't work the way they say single-layer film works, by reading the back.

I really encourage you to learn about this stuff and find your own way--to get interested in the technical aspects and experiment so that you completely understand what you're doing. Then you can make it sing. That's the best way to learn what works and what doesn't, rather than listening to a bunch of variously-qualified people. That's good advice for anything that you're serious about, I think. X-ray film is unusual in several respects: it's dirt cheap, you probably aren't using it for paying jobs, you can use a relatively bright safe light with it. These are all things that should encourage you to enable yourself to make mistakes once in a while.

In a very general way, I think you need to look for soft-working, lower contrast developers, staying away from the D19, Dektol, corner. I am not convinced, based on my results, that stand processing of this film offers sufficient (if any) compensating qualities, but the agitation I use is almost stand--once lightly, every five minutes. I would also look at a lot of people's work and find someone who does things you like with this film and try to figure out what they're doing, rather than listening to what people say without reference to their results.

tl;dr : don't listen to anyone, even me.

Vaughn
24-Apr-2016, 18:02
I have used Dektol with Agfa x-ray film -- probably 1:1. But I was going for negatives with a DR of 2.3+, so that might be a bit much for you. And I find that the ISO of the film changes with the color of the light, and has a good deal of reciprocity failure. So I would try bumping the ISO (or whatever) up a couple stops.

With film negatives I have used Dektol straight and 1:1 to get enough smooth-toned contrast increase for my printing process. A nice tool, but a bit harsh for enlarging.

Perhaps a developer like Ilford PQ Universal Developer might work nice for you. Finding it in the 5 liter jug is great, but difficult. It is 1:9 for paper, but for film it can be used at 1:9 to 1:19, depending on the contrast desired. I have used it for many years...just need to find a source of the 5 liter jugs (just saw that B&H has them for $50!)

http://www.ilfordphoto.com/Webfiles/2011427123181979.pdf