Re: Images shot on X-ray film
Quote:
Originally Posted by
desertrat
What looks like base fog might be safelight fog. The X-ray films I use are very sensitive to even a deep red safelight. Try handling and developing a few sheets in total darkness and see if there is less fog.
Thanks for your clues, I have meanwhile made one more exposure series with two ColorCheckers (for the gray wedges and to judge color sensitivity) as EI 10, 12, 25, 50. Will also test souping times, and Rodinal.
The safelight can't be the cause of fog because in the image above, the narrow strip was taken out in the dark, developed in the dark, and fixed in the dark. The level of gray matches with the adjacent picture's holder margins.
Perhaps I should lay out some of the trimmings in the safelight for long periods to see how much fogging appears when.
Re: Images shot on X-ray film
Quote:
Originally Posted by
towolf
I made two more test shots today and would really appreciate an expert opinion.
Since everybody is talking about ISO 100 in this thread I metered as EI 100 and got 1/10 at f22. I made two shots.
- EV 12.6, f22, 1/10, developed for 6 min in Refinal
- EV 12.4, f22, 1s, developed for 2 min in Refinal
http://i.imgur.com/kUu7NLNl.jpg
The lower one was basically shot at EI 10, 3.3 stops "pull". Yet it looks so much better than the top metered at 100. And I held the incident meter in the midst of those flowers, they were not in the shadows. And somehow the table top is blown out in the top version. It got a much too strong contrast. So it can’t be "ISO 100", can it?
The margin has "K O D A°K XDM" imprinted on it.
http://imgur.com/7YBKEfol.jpg
How would I proceed here? I need to know what to meter, and how long to develop.
How long to develop is relatively easy. As long as you use a ruby red safelight. Or led's of the correct spectrum. Remember that X-ray film is orthochromatic. The amber safelight that many use for papers will cause fogging. I use the same safelight for both. Ruby red. A quick check of your safelight is with a cd. When you hold it up in front of a safelight, and you see anything but red off the cd, either the light is not good enough, or you have light leaks in your darkroom. Now, to develop. The way I've done this (about 70 years with ortho film), is to develop until the image looks over developed in the tray, pull it out and look at the red safelight through the back (non emulsion) side of the negative. When you see some shadow detail through the back side, put in the water tray, and don't agitate for at least 2 minutes, then the hypo, and wash. The reason for using a plain water bath without agitation is this allows more shadow detail to come through, as the developer, which is already exhausted in the high lights, will continue working on the shadows. How long to keep it in the water bath comes with experience. Fortunately or un-fortunately, successful photography is much more an art than it is a science. That is the joy of it, isn't it? New comers to this style of work tend to pull the film out of the developer too soon. That's why you look through the back side.
Re: Images shot on X-ray film
now to exposure with a light meter. I use a Weston Master lll light meter, because it's the easiest one to use of the too many different kinds I have owned. To start with, go out and pick a general scene, one that does not have extensive interesting shadows, or blazing high lights,between 11 AM and 3 PM standard time, meter it (reflected light meter) and shoot it. Go inside and develop it the way I said in the above post. If the box says 80, shoot it at 80. Now you have a baseline exposure. Don't decide it is under-exposed until you print it. I exposed some Arista ortho-lith at 25 one time, developed it and the neg looked terribly under exposed, but when I printed it, it was fine. The print took a 45 second exposure, as I recall, but it was fine. I don't have a scanner, so I don't know how it would have looked with one. I had some of my 4X5's scanned by a friend of mine, and they weren't any where near as good as my wet prints. And I am not a great printer. I try to shoot so I can print it straight. OK. Why 11 to 3 for the time of day? Because that's when the sky has the least amount of red light. Earlier and later than that, and you have to extend exposure. Generally, one stop more exposure for every two hours earlier or later. I do not let my film spend a lot of time even exposed to a safelight. It will react even to red light given enough exposure. Hope all of this helps you.
Re: Images shot on X-ray film
My old boots - baught them in 1977 - not quite time to throw them out.
CSX Green 8X10 / Reinholds 335mm Wollaston Meniscus
https://dl.dropboxusercontent.com/u/...62/img353a.jpg
Re: Images shot on X-ray film
Thank you for the break-down premortho. If you have 70 years of experience, you started with 15 and are 85? Then you have 5 years more experience than my father.
Quote:
Originally Posted by
premortho
How long to develop is relatively easy. As long as you use a ruby red safelight. Or led's of the correct spectrum. Remember that X-ray film is orthochromatic. The amber safelight that many use for papers will cause fogging. I use the same safelight for both. Ruby red.
I’m using a faint distant (behind the shoulder) darkroom red bulb and a flexible "torch" that I taped a Schott RG 2 filter (1% cut-off 622nm, higher than Kodak GBX-2) in front of, to be able to shine a less faint spot onto the table and move the tray into and out of the spot.
http://i.imgur.com/oIhw7yl.jpg
I’m able to develop by eye to a similar level of global exposure. But I’m still trying to figure out, which EI I should pick. I think 25 is reasonable in terms of practicality. But in my next example I also used EI 6 (far left) and got yet more detail in the shadow.
http://i.imgur.com/I3ryLb1l.jpg
Of course I will keep your method with the shadow detail and the long water stop in mind for the next time. Until now stop bath for me meant a rapid complete stop. Your idea is interesting. Perhaps this will give me that shadow detail.
Quote:
Originally Posted by premortho
If the box says 80, shoot it at 80. Now you have a baseline exposure.
That’s my problem. The box doesn’t say anything. There’s no box. Just 138 brown envelopes. So I made a series 6, 10, 25, 50, 100 and developed them by eye to a "normal" global density. How do I pick the best combination? By taste?
Your points about the color of light are interesting. I have a Sekonic digital meter and the manual doesn’t list its spectral sensitivity. I want to shoot indoors and have a fairly daylight looking surface light. But I’m sure it goes towards the red end. Any tips about how much compensation "daylight color" fluorescent lights need? How about tungsten?
Re: X-ray Film example and comparison.
I picked up some Carestream/Ektascan B/RA this week from a forum member. In the interest of adding to the chorus of exposure and development tests, here is mine. I apologize for the boring photo, but I needed a nearby subject with a wide scene brightness range to see how well I could keep the contrast in check.
Camera: Pacemaker Speed Graphic
Lens: 210mm f/5.5 Hugo Meyer Doppel Anastigmat
Film: Ektascan B/RA
EI: 100
SBR: 6 stops (EV 10 to EV 16)
Meter: Pentax Digital Spot
Exposure: 1/4s @ f/45
Developer: HC-110 1:63 (dil. H) @ 68°F
Time: 4 minutes (rotary)
http://www.kolstad.us/ebay/4x5-EKTAS...03-4MinDev.jpg
Jonathan
Re: X-ray Film example and comparison.
Quote:
Originally Posted by
jcoldslabs
I picked up some Carestream/Ektascan B/RA this week from a forum member. In the interest of adding to the chorus of exposure and development tests, here is mine. I apologize for the boring photo, but I needed a nearby subject with a wide scene brightness range to see how well I could keep the contrast in check.
Camera: Pacemaker Speed Graphic
Lens: 210mm f/5.5 Hugo Meyer Doppel Anastigmat
Film: Ektascan B/RA
EI: 100
SBR: 6 stops (EV 10 to EV 16)
Meter: Pentax Digital Spot
Exposure: 1/4s @ f/45
Developer: HC-110 1:63 (dil. H) @ 68°F
Time: 4 minutes (rotary)
Jonathan
I think it worked out quite well...
Re: X-ray Film example and comparison.
Quote:
Originally Posted by
djdister
I think it worked out quite well...
It took four sheets worth of tests to get to this point. I am definitely happy with the range of tones. Now it's time to find a suitable subject and shoot some full 8x10 sheets.
J.
Re: X-ray Film example and comparison.
Yeah, nice tones, looking forward to your "real" photos Jonathan! Hope you are doing well.
Re: X-ray Film example and comparison.
Thanks, Bryan. Yeah, I'm OK, just still struggling to find my photo mojo is all. But I'm still lurking around here as much as ever even if my posts are few and far between.
J.
