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Tin Can
13-Mar-2015, 15:26
I posted this in one of the X-Ray threads and got no feedback.

The link is below.

Any ideas and info welcome.


http://www.largeformatphotography.info/forum/showthread.php?80011-Images-shot-on-X-ray-film&p=1225996&viewfull=1#post1225996

Jody_S
13-Mar-2015, 18:47
If you're looking for encouragement, go for it? I would try it, if I had the film. Why not?

I just did a quick google search for B&W UV images and the results weren't pretty. I would avoid doing portraits, unless you want to make people look sickly and dirty. I didn't see any landscapes or architectural, in my quick search. Just sickly people and odd flowers.

Tin Can
13-Mar-2015, 20:08
If you're looking for encouragement, go for it? I would try it, if I had the film. Why not?

I just did a quick google search for B&W UV images and the results weren't pretty. I would avoid doing portraits, unless you want to make people look sickly and dirty. I didn't see any landscapes or architectural, in my quick search. Just sickly people and odd flowers.

Yes, one of my links showed that.

Not everybody desires conventional worldview, is my answer.

I am seeking more technical reason why it may not work at all. If an UV/IR machine contact copy takes 10 seconds, perhaps a sunlight only exposure in camera with small stop may takes hours. Hard to estimate the speed of this unknown, except as you suggest empirical testing.

I may just try it, but first a little more research, which is what this thread is about.

Thanks Jody!

Tin Can
15-Mar-2015, 15:28
I'll just keep talking to myself.

If I used this film would I need an IR filter?

From, https://www.schneideroptics.com/pdfs/filters/WorldOfFilters.pdf

I got this info.

130903

stiganas
15-Mar-2015, 15:57
Maybe I miss something but where the IR part come from ? As I read this film is sensitive only to UV.

IR is on the other end of the spectrum so I assume it has even less sensitivity.

An IR filter will cut the UV and the visible.

Tin Can
15-Mar-2015, 16:26
Maybe I miss something but where the IR part come from ? As I read this film is sensitive only to UV.

IR is on the other end of the spectrum so I assume it has even less sensitivity.

An IR filter will cut the UV and the visible.

Thank you, I said I don't understand this topic, but want to figure out if this film is usable for art photography purposes and if so how to use it.

Your answer definity helps!

Jody_S
15-Mar-2015, 17:35
I'll just keep talking to myself.

If I used this film would I need an IR filter?

From, https://www.schneideroptics.com/pdfs/filters/WorldOfFilters.pdf

I got this info.

130903
If you read the same page I did (www.ultravioletphotography.com), there was a big discussion of filtration, but that was to use a full-spectrum sensor for UV photography. Since you have UV-only sensitive film, you shouldn't need any filtration at all. What you really need is a spectral sensitivity curve for the film, that will guide you on subjects and compensating exposure for different lighting situations. If you can't find the curve, just take a photo of a color chart in broad daylight, to see if the film is sensitive into the visible light range.

I doubt if the film will be usable in any standard artificial lighting, as everything that emits UV has coatings to block it, to reduce the health hazards for humans.

However, you could get a couple of old tanning lamps if you wanted to experiment. I have an old 500W one upstairs that I planned on using for alt processes, that was banned because it causes cancer (it has the correct UV band emissions that I need for my hybrid biochemical process I'm working on). But more modern UV lamps are safer. They're cheap and easy to find, most people have clued in that they're not really safe to use.

Tin Can
15-Mar-2015, 17:44
If you read the same page I did (www.ultravioletphotography.com), there was a big discussion of filtration, but that was to use a full-spectrum sensor for UV photography. Since you have UV-only sensitive film, you shouldn't need any filtration at all. What you really need is a spectral sensitivity curve for the film, that will guide you on subjects and compensating exposure for different lighting situations. If you can't find the curve, just take a photo of a color chart in broad daylight, to see if the film is sensitive into the visible light range.

I doubt if the film will be usable in any standard artificial lighting, as everything that emits UV has coatings to block it, to reduce the health hazards for humans.

However, you could get a couple of old tanning lamps if you wanted to experiment. I have an old 500W one upstairs that I planned on using for alt processes, that was banned because it causes cancer (it has the correct UV band emissions that I need for my hybrid biochemical process I'm working on). But more modern UV lamps are safer. They're cheap and easy to find, most people have clued in that they're not really safe to use.

Yep we used those stupid tanning lights in Minnesota in the 50's. My father had skin cancer. We also had the shoe store fluoroscopes that ruined my feet...

I would think the film may work in sunlight?

http://commons.wikimedia.org/wiki/File:Solar_Spectrum.png

Tin Can
15-Mar-2015, 17:47
If you read the same page I did (www.ultravioletphotography.com), there was a big discussion of filtration, but that was to use a full-spectrum sensor for UV photography. Since you have UV-only sensitive film, you shouldn't need any filtration at all. What you really need is a spectral sensitivity curve for the film, that will guide you on subjects and compensating exposure for different lighting situations. If you can't find the curve, just take a photo of a color chart in broad daylight, to see if the film is sensitive into the visible light range.

I doubt if the film will be usable in any standard artificial lighting, as everything that emits UV has coatings to block it, to reduce the health hazards for humans.

However, you could get a couple of old tanning lamps if you wanted to experiment. I have an old 500W one upstairs that I planned on using for alt processes, that was banned because it causes cancer (it has the correct UV band emissions that I need for my hybrid biochemical process I'm working on). But more modern UV lamps are safer. They're cheap and easy to find, most people have clued in that they're not really safe to use.

Oops I just looked at your link.

They we go, looking good and weird to me!

Jody_S
15-Mar-2015, 20:05
Yep we used those stupid tanning lights in Minnesota in the 50's. My father had skin cancer. We also had the shoe store fluoroscopes that ruined my feet...

I would think the film may work in sunlight?

http://commons.wikimedia.org/wiki/File:Solar_Spectrum.png

Yes, it will work in daylight, but you'll have a heck of a time calculating exposure. UV present in daylight depends on thickness of the ozone layer, amount of moisture in the air, time of day (angle of sun relative to you changes the distance sunlight travels through the atmosphere, which filters UV). Etc. Again, this is assuming the film is sensitive to UV only, and I'll assume it's sensitive to near-UV, that is it works with standard 'black light' fluorescent sources. Near-UV is abundant in natural sunlight, it's the shorter wavelengths that are most filtered through the ozone layer (and these are the ones that cause cancer). You could simply monitor the local weather station for their 'UV index' during the summer, that would be a rough guide.

It's possible the film was designed to work with short-wavelength sources of light such as the anti-bacterial lights used in hospitals, food prep areas, etc. But I think that's unlikely. An old-style UV tanning light puts out a full range of UV, because the short wavelengths tan you a lot faster (besides causing cancer and damaging your eyes). The one I have came with a primitive light stand that's ideal for studio lighting of tabletop still lifes.

Tin Can
15-Mar-2015, 20:28
Yes, it will work in daylight, but you'll have a heck of a time calculating exposure. UV present in daylight depends on thickness of the ozone layer, amount of moisture in the air, time of day (angle of sun relative to you changes the distance sunlight travels through the atmosphere, which filters UV). Etc. Again, this is assuming the film is sensitive to UV only, and I'll assume it's sensitive to near-UV, that is it works with standard 'black light' fluorescent sources. Near-UV is abundant in natural sunlight, it's the shorter wavelengths that are most filtered through the ozone layer (and these are the ones that cause cancer). You could simply monitor the local weather station for their 'UV index' during the summer, that would be a rough guide.

It's possible the film was designed to work with short-wavelength sources of light such as the anti-bacterial lights used in hospitals, food prep areas, etc. But I think that's unlikely. An old-style UV tanning light puts out a full range of UV, because the short wavelengths tan you a lot faster (besides causing cancer and damaging your eyes). The one I have came with a primitive light stand that's ideal for studio lighting of tabletop still lifes.

I remember the stand too, we used the darn thing in the basement. It was nearly the only thing in the basement.

I guess I won't buy any UV X-Ray film as I have a flashbulb mission also...

Thanks for all your help Jody.

Taija71A
15-Mar-2015, 22:18
I posted this in one of the X-Ray threads and got no feedback. The link is below. Any ideas and info welcome.


... I guess I won't buy any UV X-Ray film as I have a flashbulb mission also...
__

Randy... You only made Eighteen (18) 'Posts' yesterday.
Are you in competition with Stone... Or just trying to 'sp*m' the Forum?

*Your interest in UV X-Ray Film... Lasted (what?) -- All of 3 'whole' days.
--

“I think a lot more decisions are made on serendipity than people think.
Things come across their radar screens and they jump at them.”

~~ Jay W. Lorsch. ~~
________

Tin Can
22-Mar-2015, 11:41
Did a little more searching and found this very informative IR UV article. http://www.photonics.com/EDU/Handbook.aspx?AID=32169

Photonics is the future in many ways.

Tin Can
23-Apr-2015, 14:19
And this.

http://www.markerink.org/WJM/HTML/uv-tips.htm

Louis Pacilla
24-Apr-2015, 06:32
__

Randy... You only made Eighteen (18) 'Posts' yesterday.
Are you in competition with Stone... Or just trying to 'sp*m' the Forum?

*Your interest in UV X-Ray Film... Lasted (what?) -- All of 3 'whole' days.
--

I think a lot more decisions are made on serendipity than people think.
Things come across their radar screens and they jump at them.

~~ Jay W. Lorsch. ~~
________

Man ain't that the truth.:rolleyes:

Tin Can
24-Apr-2015, 15:19
Now this does talk to me.

http://www.naturfotograf.com/UV_IR_rev01UV.html

Jody_S
24-Apr-2015, 16:22
Now this does talk to me.

http://www.naturfotograf.com/UV_IR_rev01UV.html

Makes me think that if you wanted to use LF for UV photography, you could solve the difficult exposure problem by using your dSLR (with the proper filters) as a light meter. Once you do your tests, you just take a bunch of shots with the dSLR until your histogram looks good, then adjust up or down the correct number of stops for your LF setup. This might not work if the UV film is sensitive to more of the UV bandwith than the dSLR's sensor.

Tin Can
24-Apr-2015, 16:32
http://www.naturfotograf.com/uvfilms.html

Jody, yes!