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I've only handled 2 kinds of XRay film a double sided and a single sided. Cxs green a Ektascan B/RA which has an anti halation backing. The developer soluble backing is blackish and the emulsion is pink/light colored. Double sided is pink/light both sides.
Rodinal 1:100 might be a place to start with film exposed mid day as if ASA100. There are dozens of developing schemes in this thread though.
I'm searching here and with google, but I can't find X-ray film in 12x15" in Europe.
Can anyone help me?
It would take a very long time to read through four thousand posts to find those that involve Rodinal and X-ray film.Quote:
Originally Posted by Fr. Mark
Those posts I have read mention a 1:200 dilution for 6 minutes or 1:100 for 4 min. At 1:200 it would be easier to judge the right moment if developing by inspection. It remains to be seen how the Crontex film & the dental stuff reacts to that developer.
If I wish to develope by inspection, then I need to leave a blank sheet of film out under the red light for ten minutes (half covered). Any fogging warns me I must restrict any lighting. Is that a reasonable practice when wanting to tray develope X-ray film?
I try to read each new post in this thread, as posted, but I can't remember what film we're talking about, but... FWIW, I process Ektascan B/RA in Rodinal 1:100 at 20C for 6 mins in an Expert Drum on my Jobo (slowest speed.) I hope this helps someone extrapolate a useful time for themselves. Though I've never used the Kodak Green sensitive film or any of the double-sided films, it seems development times for these products are quite a bit different vs Ektascan.
I have never done tray developing. If you knew a film took 6 minutes in whatever juice in a tank, then it would be the same or pretty close for a tray? I am assuming that the different agitation regimen will make some difference.
Does there have to be a certain amount of chemistry present to develope a 4x5 sheet. I would have thought this is especially relevant if we were using Rodinal 1:100.
Proper timing for tray development might or might not be the same as continuous agitation such as in a Jobo drum, depending on how you agitate in the tray. If you use continuous agitation in a tray, I'd think the development times between this and something like a Jobo drum would be about the same. If your tray agitation is 10 secs out of each minute, then I'd suspect this will require slightly longer development times. Generally, the difference in development times between intermittent agitation and continuous is usually about 10 - 15%. However, this can vary depending on if you pre-rinse or not.Quote:
Originally Posted by Neil Purling
I seen quite conflicting information regarding the minimal amount of stock Rodinal required to properly develop a sheet of film. For example, with 8x10 (what I shoot) I've seen everything from 3ml to 6ml, minimum, required. In my Jobo drum, I typically use 500 - 1000ml of diluted solution--so, 5 - 10ml stock Rodinal--to develop a couple of sheets to a full drum (5 sheets.)
12x15" = 30x40cm (approximately) - http://www.bema-kg.de/Typon-DV-G-30x40-cm-100-Bl any use? Probably others in there too.Quote:
Originally Posted by Peter Volkmar
Don't know what the film is like though I am waiting for some to play with.
Neil
X-ray film is orthochromatic and can be handled under red light. Why then does it not render skin tones darker like the ortho film of old? Skin with x-ray film looks closer to pan film than ortho. Mind you, I'm fine with that. I'd just like to understand what's going on. Is it that the ortho of old was less sensitive to a wider range of wavelengths?
I suspect it mainly due to the emulsion's differing reaction to light. I know...duh. :) Orthochromatic emulsion has a relatively high sensitivity to blue, generally correct sensitivity to green and bright yellow, but has relatively low sensitivity to orange and is nearly insensitive to red. This film doesn't register wavelengths longer than about 560-600 nm. It also has decreased sensitivity in the 500 nm area.Quote:
Originally Posted by Peter De Smidt
Xray film is generally either green or blue sensitive. I couldn't find any data referencing its wavelength sensitivity range, but I'd guess it differs in key ranges when compared to orthochromatic film. Of course, nothing I've said here answers your question regarding the rendering of skin tones...I'm simply postulating. ;)
In printing it's possible to make people look less "swarthy", so you wouldn't notice that part, but it does render skin darker, shows up red skin defects (which turn out to be all over the place, and does strange wonderful things with blue eyes. I have to do quite a bit of retouching of my portraits of women because of these things, and that's one of the reasons I'm experimenting with soft focus lenses. But it does none of this as extremely as collodion, for instance.
The other effect is that under incandescent lights the speed drops, drops, drops.