Question from a child I could not answer.

[larrydressler]

I was explaining differant types of film and Their effects were with my 16 year

old daughter who loves photography and using a real dark room.

 

While explaining Ortho and Infa Red films she asked me. Are there any Ultra

Vilot films and what is the effect. DdOOOOOOHHHHHHH I never even thought of it

as to why there was none that I could ever remember. She understood the

differance in focus with IR and wanted to also know where the UV mark would be.

I told her it would be on the other end of the IR focus mark but that is as far

as I got.

 

Any ideas or info to help me?

 

Larry

[randall ellis]

I don't know a whole lot about it, but here are some links from my bookmarks folder...

 

http://mywebpages.comcast.net/hmpi/Infrared/Articles/Ultraviolet/Uvphoto.htm

 

http://www.srs.fs.usda.gov/4505/hanula/pollinator_studies/uv_photography.htm

 

- Randy

[robert hall]

HIE has a substantial UV sensitivity. One needs only a filter and a lens that will not block the UV. As I recall, normal glass doesn't block UV but the crystal lenses do.

 

Have her take a look at my site under the "how to" section.

 

Good luck!

 

Robert Hall

 

http://www.RobertHall.com

[franklin_polk]

There are indeed UV films, as there are UV lenses, although I cannot think of any films specifically off of the top of my head. To get the entire UV spectrum recorded, you need special lenses. Optical galss blocks out around 98% of UV rays (although it is possible to utilize that 2% on digital, apparently; google digital UV photography), so special lenses made of quartz and other exotic (and expensive) materials are needed. (Pentax made an 85mm lens and Nikon has their 105mm f/4.5 UV micro nikkor, I'm sure there are otehrs) I personally haven't done UV photography, although I've talked with people who have; I'm sure someone on this board can correct me if I'm wrong.

[jon_noble]

Bjorn Roslett specialises in this kind of photography

 

http://www.naturfotograf.com/index2.html

[larrydressler]

Randall and everyone else. I thank you I marked all the links you gave me.

 

I knew I could count on you guys. this is why Film will never die. I knew that most film had a UV sensitivity otherwise we would not have UV filters. I guess the simplest answer would be that most lenses that are cheap enough to use by the adverage photographer block most U.V light. I know that NASA uses UV cameras but uses CCD cells to capture it and well NASA can afford better lenses than we can. LOL

 

Larry

[ted_marcus1]

Silver halide is sensitive to ultraviolet. Glass in lenses blocks most of what the ozone layer in the atmosphere lets through, but especially at high altitudes there's enough of it around to be noticeable as a bluish color cast with color slide film.

 

Some films have an ultraviolet filter built in to take care of most of that. A pale yellow "ultraviolet" filter will help with the blue color cast, although the main reason people use it is to protect the front element of the lens.

[piotr_panne]

For another amazingly useless trick with light get the TV remote and a digicam. Open the lens/turn it on to get a realtime image on the LCD. Looking at the screen and through the lens pointing at the remote\'s transmit end, press a command on the remote and actually see the IR light pulse.

[larrydressler]

IS it useless to know this "TRICK" ir would this information be well used to a new generation of people who were stumped wonderering Why they had this strange problem when they were trigering cameras?

 

No knowlege is useless un lest it it not used.

 

Thanks .. and someday I will own a Digi Cam and a remote.. but for now I like film and if need be I will use Coffee and Gall nuts ... what the heck is a Gall nut?

 

My Kids just learned what Hickory nuts were.

 

Larry

[chromatic-aberration]

Actually, the remote control trick isn't useless at all. It't the best way for someone thinking about trying infrared photography on a digital camera to test whether or not the camera passes a decent amount of IR before plunking down the money for an IR filter.

[Jochen_S]

I once read the manual of my pre-war Balda Rollbox. According to it the lens is set for the "chemical focus" which means further than infinity of visual light.

Silverhalogenides needed lots of reeducation to react on anything else than blue or UV light.

 

There are lots of (U)V sensitive materials used in the printing industry. Ozalith (blueprint) paper or offset plates. They react best on UV light, so they are handleable in ordinary artificial light indoors.

[discpad]

"My Kids just learned what Hickory nuts were."

 

Is that related to Prairie Oysters?

[larrydressler]

No Dan they come from Hickory trees. And my cids learned about Mountian Oysters in Montana.

 

Larry