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Ricardo de Oliveira
1-Nov-2014, 13:30
Hi all,
got a box of 18x 24 cm mammography film, Agfa HDR-C. I did two tests with yellow gelatine over a red bulb and with a bare red bulb, both more then one meter away, indirect lighting the working area, apparently weak (15 watt) and fogged both sheets.
Since I have to cut the sheets to fit 4x5 film holders and is a pain to work in the dark, I'd like to ask you experts in mammography film shooting what's the correct safelight? Or am I doomed to complete darkness?

ic-racer
1-Nov-2014, 14:01
I don't know of any red bulb that is safe for photographic purposes. Did you try an OC filter?

Will Frostmill
1-Nov-2014, 14:46
Some things that emit red light aren't as monochromatic as you need for green sensitive xray film. Try taking a CD into your darkroom, and see what colors of light (or how many bands) are reflected on the surface of the CD. A pure red LED should emit on only one band, a filtered incandescent bulb can be much wider spectrum. Red LED bulbs are available that are good for darkroom work - and some that aren't.

It's possible you've lucked into some panchromatic film, which is great. The usual suggestion is to buy a roller cutter, and tape bumpers to the bed, so that you can line up the film by feel in total darkness. I wouldn't feel lucky about using a free blade or guillotine cutter in the dark.

Ricardo de Oliveira
1-Nov-2014, 15:01
I'm taking a guillotine and taped a plastic rule over to serve as a stop. It worked first time but man...
I had just developed a pinhole shot I did at my balcony. The sheet is washing as I type. The film is GREAT. Fine grain. Contrast just right. Souped in Parodinal for 12 min. First sheet at 7 min was to thin. Exposed 100 ISO. No reciprocity. I'm really excited with my "discovery".

Tin Can
1-Nov-2014, 15:11
I have a dozen of these (https://www.superbrightleds.com/moreinfo/led-globe/2-watt-g11-globe-bulb-360-degree/440/#/attributes/13) in a 600 sq ft space. I like them.

Read the X-ray threads it's all there.

Ricardo de Oliveira
1-Nov-2014, 15:16
In red?

Will Frostmill
1-Nov-2014, 16:18
Yes, in red. Click on the tiny red square under "select color". That changes the part number and UPC to this:
Part Number: E27-R8-G
UPC: 847781014778

Sounds like great film! I'm quite excited for you.

Tin Can
1-Nov-2014, 17:29
Yep RED, look at the info on it, it has a wavelength perfect for paper and X-Ray, old timers prefer yellow, but I prefer red and consider it 'safer'.

I put them in the cheap Home Depot work light reflectors for directional usage and keep them 4 ft away.

They use so little power I leave them on most of the time.

Some are in Kodak Bullet cans for nostalgia. I wish i had more Kodak bullet cans. Much cooler looking and the wall bracket is genius.

Ricardo de Oliveira
1-Nov-2014, 17:40
Thanks for the input, gents.

stiganas
5-Feb-2016, 02:33
I just discovered that my red bulb is (moderately) fogging the xray film. I bought some red led from a hardware store and is fogging the film big time. The E27 LED Bulb, 8 LED - Red Part Number: E27-R8-GUPC: 847781014778 from superbrightleds.com everybody is happy with works only at 120V.

Can you recommend a good red led available in europe (220V) - ideally easy to buy online from amazon.co.uk or from china shop like banggood, I don't want to spend money and time testing every red bulb available locally. Thank you.

seezee
5-Feb-2016, 14:32
I just discovered that my red bulb is (moderately) fogging the xray film. I bought some red led from a hardware store and is fogging the film big time. The E27 LED Bulb, 8 LED - Red Part Number: E27-R8-GUPC: 847781014778 from superbrightleds.com everybody is happy with works only at 120V.

Can you recommend a good red led available in europe (220V) - ideally easy to buy online from amazon.co.uk or from china shop like banggood, I don't want to spend money and time testing every red bulb available locally. Thank you.

I can't recommend a specific supplier, but the important thing is you find a bulb with the right spectral output. If you look at the chart for the bulb from superbrightleds.com, you can see that their red bulbs have a narrow output that peaks at ~635nm. Find a bulb that matches that and Bob's your uncle. You definitely want to stay away from amber light for pretty much any x-ray film, and if you buy a conventional incandescent light be aware that the filtering dye fades and changes color over time, so a new bulb (or Wratten filter) may be safe, but an old one may not be.

One more thing: I, too, use a worklight with reflector & clamp (http://www.amazon.com/Bayco-SL-300-Clamp-Aluminum-Reflector/dp/B007RKKEHA), so I bought one of these (https://www.superbrightleds.com/moreinfo/empty-bases-sockets/dual-e27-base-to-e27-base-socket-adapter/2327/5670/) in order to double my light output. Works a treat; there should be something similar in 220v for your part of the world.

stiganas
6-Feb-2016, 09:31
Thank you,

I folowed your advice and bought a led bulb from dx.com

A0029 E27 3W LED Lamp Globe Bulb 700nm Red Light 210lm SMD 2835

Power 3W
Rated Voltage AC 220V
Connector Type E27
Emitter Type 2835 SMD LED
Total Emitters 9
Color BIN Red
Theoretical Lumens 210lumens
Actual Lumens 190~210lumens
Color Temperature No
Dimmable no
Beam Angle 150
Wavelength Red: 635~700nm

It was one of the few with a wavelength in the description. Now I have to wait a month or more.

Tin Can
6-Feb-2016, 09:39
Great. Notice it is 3 watt and it may be best to bounce the light off a wall. Good idea to test and report as I am sure you are not the only one needing a good LED. :)



Thank you,

I folowed your advice and bought a led bulb from dx.com

A0029 E27 3W LED Lamp Globe Bulb 700nm Red Light 210lm SMD 2835

Power 3W
Rated Voltage AC 220V
Connector Type E27
Emitter Type 2835 SMD LED
Total Emitters 9
Color BIN Red
Theoretical Lumens 210lumens
Actual Lumens 190~210lumens
Color Temperature No
Dimmable no
Beam Angle 150
Wavelength Red: 635~700nm

It was one of the few with a wavelength in the description. Now I have to wait a month or more.

Rick A
7-Feb-2016, 06:30
Yep RED, look at the info on it, it has a wavelength perfect for paper and X-Ray, old timers prefer yellow, but I prefer red and consider it 'safer'.

I'm an "old timer" and never preferred yellow, in fact, I have only used dark red safe lights since my first dark room in 1964.

Jim Noel
7-Feb-2016, 11:50
I still have a small supply of "Ruby" bulbs from the 40's or 50's. They are bright and emit only the correct part of the spectrum for ortho films. Wonderful to work with.

Tin Can
7-Feb-2016, 12:36
I still have a small supply of "Ruby" bulbs from the 40's or 50's. They are bright and emit only the correct part of the spectrum for ortho films. Wonderful to work with.

How were they made?

Actual rubies?

Have you checked the diffraction spectrum with prism? These days some check with CD.

Not joking, curious.