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Thread: Use of X-ray film: technical discussion with example images

  1. #5791

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    Re: Use of X-ray film: technical discussion with example images

    Quote Originally Posted by Paul Kinzer View Post
    I found one today at Goodwill, and it is mine: Hand's off 'wifey'!

    I considered plastic, but wasn't sure if certain plastics might be chemically problematic. I also thought that glass would stay smooth, while plastic might get scratch-inducing scrapes and gouges after use and storage. But, when I go to the 14x17, I'll look harder at plastic.
    Kitchen stores have something called bain marie trays. usually full size,half size, quarter size. They are usually stainless steel. Maybe craigslist or offerup and look at the used kitchen places going out of ---yikes--covid-out-of-buisiness.
    --

  2. #5792

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    Re: Use of X-ray film: technical discussion with example images

    Quote Originally Posted by ericantonio View Post
    Kitchen stores have something called bain marie trays. usually full size,half size, quarter size. They are usually stainless steel. Maybe craigslist or offerup and look at the used kitchen places going out of ---yikes--covid-out-of-buisiness.
    I did some looking around, and as far as I can tell, the largest size available is not quite big enough for 14x17 film. The dimensions of the 'full' size are 500 x 325 mm, which is about 20 x 13 inches. The corners are also very rounded, so the actual dimensions of the opening is even smaller. But maybe I just haven't searched hard enough yet. I'll keep looking for other stainless steel options, because I really like it as a permanent solution. My darkroom is going to be my upstairs bathroom, and I'll need to be able to transform it from one use to the other fairly easily/quickly. I see a hinged, shallow shelf attached to the wall above our claw-foot tub.

    Stainless steel is a better choice for this, I think, than either glass or plastic. I have a book with some different solutions, and one includes a DIY fiberglass tabletop with depressions for large sheets, but my skill set would work better with steel trays secured to a plywood sheet with holes for setting the trays in. Like a very large but shallow kitchen sink.

  3. #5793

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    Re: Use of X-ray film: technical discussion with example images

    I've been struggling with scratches from handling, cutting and loading Fuji HR-U film. Some people seem to have an easy time with this while others claim that if you so much as look at the film it scratches. I'm in the latter camp. I'm mostly talking about micro scratches that you really only see when you scan or enlarge the negative or look very closely under strong light. You can get these scratches on HR-U by touching the film with your fingers, sliding it into film holders, sliding it across the paper cutter table, etc. For those who have this figured out, are we are talking about same thing? I'm going to call the fine scratching "micro scratches" to differentiate from obvious scratches.

    I have been using an X-ACTO guillotine trimmer like this that I had in my studio for other art. It has served me well in the past and is of reasonable quality.
    https://www.amazon.com/X-ACTO-Commer.../dp/B002JGMIA8

    The first problem I had was that there was a raised burr on the fixed blade at the edge of the table from use. As I slid the film into position, I left obvious scratches in the bottom emulsion across the entire film. I was able to resolve this by removing the burr with a diamond stone, which also improved cutting performance slightly.

    Second problem: micro scratches from dragging the film across the clean table and holding it down to cut it. The table on this model is made of MDF coated with a smooth plastic with an inset grid. It is not rough feeling. I solved this by laying tracing paper across the table and on the counter below, which has the added benefit of keeping things clean. FWIW, tracing paper is also capable of scratching HR-U if you rub them together, but I am more careful to place the film nearly in position rather than slide it into position now.

    Third problem: no backstop to set the size of cut. I tried taping a 30/60/90 triangle to the table as a guide and later clipping a large binder clip on the top rail. Both work but are finicky to set in the near dark.

    Fourth problem: holding the film in place while cutting. My film is 14x17 so I need to hold it still for long cuts and it doesn't have any kind of provision for this. Putting a ruler or any other surface that might scratch the film down on it is a non-starter for micro-scratches. The best I came up with is to rest my forearm on the film while making the cut, though this gets skin oil on it. With this only about 80% of my 4x5 pieces are perfect. Good thing it's so cheap.

    Fifth problem: micro scratches from handling. Nitrile gloves seem to fix this.

    Sixth problem: The film can scratch itself, so I am careful to stack the cutoffs neatly and only once.

  4. #5794

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    Re: Use of X-ray film: technical discussion with example images

    In my hunt for a better solution than my X-ACTO guillotine for cutting X-ray film, I have a couple of paper cutter reviews to share.

    First I tried a fancy Dahle 552 rotary trimmer:
    https://www.amazon.com/Dahle-552-Pro.../dp/B082NVFVN3

    Click image for larger version. 

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    This is a nice tool and I especially appreciated its adjustable backstop and build quality. It makes nice cuts in paper and film. However, it is a bit of a counter top space hog. It is designed to cut in both directions, so the cutting head moves entirely beyond the cutting area by about 4" on both ends. The other problem I had with it was that I couldn't figure out how to load the film into it without dragging the film over the backstop, across the table and under the clear plastic guard. I know from experience that this will create micro scratches on HR-U. Finally, the plastic guard, which applies downward pressure when you cut is not soft and may also scratch the film. Here you can see that you have to load the film over the backstop and under the clear/bluish hard plastic guard:

    Click image for larger version. 

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    Given the high cost and drawbacks, I decided to return this cutter and look for a better guillotine.

    Today, I got the Dahle 18e Vantage, which is really cheap at $57 on Amazon:
    https://www.amazon.com/Dahle-Automat.../dp/B000W1YNNW

    This is a metal bodied cutter with a soft rubber (squeegee material) foot that comes down with the blade to hold the film in place. Amazon has a little video of it in action. I like that the rubber is unlikely to scratch the film and it is able to hold the film in place for long straight cuts. The cuts in film are nice and smooth. The metal body is solid and strong while being a bit lighter than my smaller wood X-Acto. For film cutting, the blade and foot get entirely out of the way, allowing me to place the film rather than drag it or slide it into place.

    However, it has two flaws. First, the cutter arrived out of square, possibly enough that film cut using it wouldn't fit into a film holder. I was going to return it but I figured out that you can loosen 4 screws on the underside of the top rail and adjust it. It took about 30 min of fiddling but it is now square. Second issue is the terrible backstop, which is bowed to the point where film will slide under it rather than stopping in position and so flimsy that it doesn't really hold things square to the top rail. The one from the fancy 552 model is dramatically better. I have no fix for this. I thought I might be able to buy a 552 model stop (they are available for $20) but I wasn't sure if it would fit the rail since the 552 stop did not fit my X-ACTO guillotine rail. Since the table is metal, I am now using a 30-60-90 triangle held down with some magnets, which is easy to adjust in dim light.

    Click image for larger version. 

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  5. #5795

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    Re: Use of X-ray film: technical discussion with example images

    I've also been struggling to find a bare red safe light bulb that won't fog HR-U. I have tried four so far with no success. For posterity here's what doesn't work:

    - Halco 11W Red Safelight Bulb, $4.29 from Freestyle. Unsafe at any distance for HR-U.
    https://www.freestylephoto.biz/12622...Safelight-Bulb

    - A single red LED in my headlamp pointing towards the ceiling is safe (left negative). Direct exposure to the LED at about 1 foot is unsafe but only the direct beam (right negative).
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    - Super Bright LEDs 7.5W Red globe (E27-R8-G). Mostly unsafe. This bulb will heavily fog HR-U in all but the most dim / distant reflected use. Direct exposure will render the film totally black. I am currently still using this one but it is bounced off the rear wall of the darkroom for a total travel of about 15' before it gets back to the work area. For reference, it is safe when it is so dim that you can only barely see well enough to handle the film after 10 minutes of eye adjustment. I really do not like using the paper cutter in these conditions.
    https://www.superbrightleds.com/more...mens/440/1477/

    - Byingo LED Grow Light Bulb - 25W 660nm All Deep Red Spectrum. $15 ea on Amazon.
    https://www.amazon.com/Pack-Byingo-G.../dp/B07ZFM4NKF

    These are totally unsafe for HR-U. They are extremely bright because they are meant to be grow lights. Here you can see the control, which was only handled w/ super bright LEDs bounced off the rear wall (left); a Byingo bulb similarly bounced off the rear wall for 1 min exposure (center); direct exposure at 1 foot for 1 minute exposure (right).

    Click image for larger version. 

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  6. #5796

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    Re: Use of X-ray film: technical discussion with example images

    Paul, you can kind of use anything that will hold water and put glass in the bottom if it's not smooth. It has to be /really/ smooth if you're going to let the wet emulsion touch it.

    I have moved entirely to vertical tanks and film hangers, which I have found to have a lot of benefits over trays: the vertical tanks can do multiple at the same time; with proper agitation technique, the chemicals are exposed to both emulsions equally; except for the edges, no part of the emulsion touches anything ever during development.

    If you're going to build or buy something, I suggest film hangers and vertical tanks.

    Here's Mat Marrash running through his workflow, which is pretty much where I'm landing.
    https://www.youtube.com/watch?v=G1OI...nel=MatMarrash

  7. #5797
    Tin Can's Avatar
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    Re: Use of X-ray film: technical discussion with example images

    I bought three SS 1/2 size chafing trays from Costco, very cheap

    I use them only for 7x17

    I think it's the same as 20X13

    Quote Originally Posted by Paul Kinzer View Post
    I did some looking around, and as far as I can tell, the largest size available is not quite big enough for 14x17 film. The dimensions of the 'full' size are 500 x 325 mm, which is about 20 x 13 inches. The corners are also very rounded, so the actual dimensions of the opening is even smaller. But maybe I just haven't searched hard enough yet. I'll keep looking for other stainless steel options, because I really like it as a permanent solution. My darkroom is going to be my upstairs bathroom, and I'll need to be able to transform it from one use to the other fairly easily/quickly. I see a hinged, shallow shelf attached to the wall above our claw-foot tub.

    Stainless steel is a better choice for this, I think, than either glass or plastic. I have a book with some different solutions, and one includes a DIY fiberglass tabletop with depressions for large sheets, but my skill set would work better with steel trays secured to a plywood sheet with holes for setting the trays in. Like a very large but shallow kitchen sink.
    2022

  8. #5798

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    Re: Use of X-ray film: technical discussion with example images

    whoop! Got my "flat bottom girls" in today from B&H. Nice quality on those. Not like old school ceramic quality but not bad. I'll mark it "ONLY FOR XRAY".

    I will develop Fuji HR-U today. Afternoon sun, pinhole camera, rated I don't know...50? I think I had 2 minute exposures in afternoon light.

    I'm thinking PMK, 1:2:100 21 degrees. 14 minutes?

    I am metering, shooting, and processing for future PT/PD prints so if you have anything "punchy" you can recommend I'm all ears (or eyes in internet). I can make D76, I have hc110, and I have PMK.
    --

  9. #5799
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    Re: Use of X-ray film: technical discussion with example images

    as the Sun fails in season, compensate for Sunny 16
    2022

  10. #5800

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    Re: Use of X-ray film: technical discussion with example images

    Quote Originally Posted by Tin Can View Post
    as the Sun fails in season, compensate for Sunny 16
    Not sure what you mean but this is what I pictured as you were saying that.

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