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FrozenGate by Avery

properties of wavelengths

Night Vision is usually facilitated by Ir light if I remember correctly.
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so there must be a UV sensor for UV video? I tried to do a search a while back and didn't find anything. I know there are starlight scopes too that just amplify available light.
 





I don't know how they're made. But, anyone who's seen enough satellite photos in various wavelengths of the sun and its coronal discharge knows that exotic wavelength cameras exist...even X-Ray!

I imagine one would have to go to the manufacturers directly for such a sensor.
 
Taken from wiki:

The Fujifilm FinePix IS PRO digital SLR camera is purpose-designed for ultraviolet (and infrared) photography, with a frequency response rated from 1000-380 nm, although it also responds to somewhat longer and shorter wavelengths

But it needs special lenses and filters:

True ultraviolet photographic lenses are generally made from special glass because normal optical glass does not pass UV particularly well.

Reflected UV photography





A portrait taken using only UV light between the wavelengths of 335 and 365 nanometers.
In reflected UV photography the subject is illuminated directly by UV emitting lamps (radiation sources). A UV transmitting, visible light blocking filter is placed on the lens, that allows ultraviolet to pass and absorbs all visible light. Examples of these filters are Kodak Wratten 18A, B+W 403, Hoya U-340, Baader U-Filter and Kenko U-360. These filters are made from special colored glass. Most types of glass will allow long wave UV to pass, but absorb all the other UV wavelengths, usually from about 350 nm and below. Only special developed lenses made of quartz (fused silica) or quartz and fluorite can be used. Using these lenses allow the camera to reach the range 180..200 nm. Lenses based purely on quartz show a distinct focus shift between visible and UV light, whereas the later developed fluorite/quartz lenses are fully color corrected without focus shift. Examples of the latter type are the Nikon UV Nikkor 105 mm, the Hasselblad (Zeiss) UV Sonnar 105 mm and the Asahi Pentax Ultra Achromatic Takumar 85 mm.[1]

[edit] Ultraviolet fluorescence photography





Fluorescent materials lit by UV light. No filter is used to absorb violet visible light. Photo taken with daylight film by Beo Beyond.
Photography based on (visible) fluorescence induced by UV radiation has better results in archaeological photography. The same ultraviolet light sources as in reflected UV photography, except that a glass filter is used to absorb all the visible light and allow only the desired ultraviolet to pass. These filters are sometimes incorporated in the source tube itself, but most of the time are separate elements. These filter glasses usually allow a small amount of violet visible light. This should not be confused with UV light, which is invisible to the human eye. The same kind of filters are made for flash tubes also, by BALCAR and other lighting companies.

This filter is called an "exciter" filter and it allows only the radiation needed to excite fluorescence. A second filter must be placed in front of the camera lens, to exclude residual ultraviolet and allow the resulting fluorescence excited in the sample by the UV source. This filter is called the "barrier" filter. Kodak Wratten 2A - 2B is effective, as is the Baader UV/IR Cut filter. Using a 2E filter gives better results in some situations. The same filters are also made by other companies with the same codes.

The shooting must take place in a darkened room, with a black background. The photographer should also wear dark-colored clothes for better results. (Many light-colored fabrics also fluoresce under UV.)

Suitable digital cameras for reflected UV photography have been reported to be the (unmodified) Nikon D70, D40 and Fuji Film S5 cameras, but others might be suitable after having their internal filter removed. If using a modern digital camera (DSLR), it would be advisable to additionally use an IR blocking, yet UV transmissive filter to avoid IR leakage. Schott BG-38 and BG-40 are suitable for this purpose.

PS. So aparently some CCD camera does have the ability to record UV... maybe not all CCD..???
 
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Good old silver nitrate based film responds nicely to UV. You could adapt an old film movie camera to record UV. Not exactly what you're looking for though.
 
Sigurthr said:
Good old silver nitrate based film responds nicely to UV. You could adapt an old film movie camera to record UV. Not exactly what you're looking for though.
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You'd still need special lenses for it wouldn't you? As I read that regular glass lenses would block the uv...
 
I'm fairly certain that most aspheric camera lenses have UV filtering built in to increase image contrast and clarity. I am not certain though.
 
Thank you guys for the info ::): That explained a lot Norbyx. Doesn't look like there is a simple solution like a webcam or filter available SBA. ::(: Yeah Sig, maybe the old analog ways are the best :)

~ LB
 
Yes, glass blocks deeper UV (I forget where the cutoff is - 340nm maybe?), so you would need quartz lenses.

Hehe, while I do love the amazing things digital tech brings us and would never doubt its value or importance, I am an analog man at heart. Sometimes it shows.
 
Sigurthr said:
Yes, glass blocks deeper UV (I forget where the cutoff is - 340nm maybe?), so you would need quartz lenses.

Hehe, while I do love the amazing things digital tech brings us and would never doubt its value or importance, I am an analog man at heart. Sometimes it shows.
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I am with you on this one.... Digital brought many advantages in the modern world but analog was just plain quality engineering.
I still have to see a 50 year old digital camera and still work (in the future since I don't think there are camersas that are that old and still they all break).
I want to hear a CD or even a Audio DVD or blue ray in the same way you heard an old LP... plain impossible...
I want to have the sound that an analog radio receiver has and not the one of a modern DSP radio has...

Digital is good because it is cheaper and more accesible to the mass, not many could afford a leica camera back in the days when the cost of it was comparable to 4 months of a good salary, and now you get a digital camera for $50.
Not many could pay $3000 for a Collins radio in 1960 when a car was costing less than that, and now you get a DSP transceiver for $500....
And so many more examples I could bring up but don't come to the case...
 
Good thought SBA but it seems its a niche market :P It's interesting to me that we can see a different world, the way insects can see UV patterns on the flowers to identify food sources or how the sky looks different. Just kinda cool. :thinking:
 
Btw, one of the reasons CCDs can't see UV is the chip itself has a window over the sensor which blocks the light. CCDs can actually see gamma photons without much trouble, but not many gammas get stopped by the low density chip.
 
Sigurthr said:
Btw, one of the reasons CCDs can't see UV is the chip itself has a window over the sensor which blocks the light. CCDs can actually see gamma photons without much trouble, but not many gammas get stopped by the low density chip.
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Is that removable?
 
Sigurthr said:
Btw, one of the reasons CCDs can't see UV is the chip itself has a window over the sensor which blocks the light. CCDs can actually see gamma photons without much trouble, but not many gammas get stopped by the low density chip.
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That'd be trippy, a gamma ray camera...
 
Shakenawake said:
Right after I posted that I got to thinking there are probably people who can see more of the spectrum than others, just as some insects can
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I try not to be a usless poster but my post does have relevance to " properties of wavelengths" and your post

You are dang right about other creatures seeing more.. The Mantis Shrimp can practically see the whole spectrum!

"The mantis shrimp has such good eyes it can perceive both polarized light and multispectral images.[11] Their eyes (both mounted on mobile stalks and constantly moving about independently of each other) are similarly variably colored and are considered to be the most complex eyes in the animal kingdom."
--Patrick Kilday from Wikipedia
Mantis shrimp - Wikipedia, the free encyclopedia
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*edit
OMG, wannaburnstuff already beat me to the mantis shimp. I guess I didn't see that :o
Back to lasers
 
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