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or "See the World Through the Eyes of a Bee".
For years I've wanted to mess around with UV photography. Unfortunately, all the websites on DIY UV seem to assume an infinite amount of money and access to specialized equipment on my part. There are two things that I don't like, when someone tells me I HAVE to spend a lot of money (quartz lenses starting at $3000) or that i need specialized equipment (Wratten 18A filters, not cheap either).
So I set out to do it my way, and here's my $5 solution to UV wavelength photography.
For years I've wanted to mess around with UV photography. Unfortunately, all the websites on DIY UV seem to assume an infinite amount of money and access to specialized equipment on my part. There are two things that I don't like, when someone tells me I HAVE to spend a lot of money (quartz lenses starting at $3000) or that i need specialized equipment (Wratten 18A filters, not cheap either).
So I set out to do it my way, and here's my $5 solution to UV wavelength photography.
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I was wracking my brains trying to find a UV bandpass filter, when, quite literally, a light bulb went off in my head. A blacklight bulb that is. Blacklight bulbs are formed from wood's glass. Wood's glass is a uv & ir bandpass filter.
There are two kinds of blacklight bulb (at least), incandescent and fluorescent. I tested both, good for you, because the fluorescent kind DID NOT WORK. This is good because the incandescent is safer to work with, and cheaper.
There are two kinds of blacklight bulb (at least), incandescent and fluorescent. I tested both, good for you, because the fluorescent kind DID NOT WORK. This is good because the incandescent is safer to work with, and cheaper.
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I mistyped "florescences" for the term, "fluorescences" in a previous comment, and a few attempts to post comment, too. The former refers to a subject of my interests, the production of flowers and the period of doing so by a plant, whereas the latter has to do with re-emission by an object of photons at a shifted wavelength. What this has to to with UV is that some materials can be excited by UV to emit in the visible spectrum, and presumably there are cases in which the re-emission is in the UV.
Sorry if the typo caused confusion on the part of any readers.
The subject's original post had to do with the fact that glass is NOT opaque to UV in the A and B near-UV bands, but does start attenuating UV-B significantly by 330nm, I think. You can be much more specific by specifying what kinds of glass, etc., for example, flint glass would attenuate more at higher wave lengths, I think, than crown glass, and there are many glass formulations that are different from those in use in today's lenses. Also, the modern coatings, especially on zoom lenses, tend to attenuate UV, so look for simpler 4-5 element prime lenses with minimal coating to photo in UV. Also consider the simpler enlarger lenses, reversed with appropriate threaded adapters.
Some of the more significant issues would be in getting exactly coincident multiple images, so use solid tripods or camera mounts, bracket shots, consider image focal plane shift for different kinds of lenses (achromatic vs apochromatic, etc.), and have fun experimenting.
Some digital cameras have very poor anti-aliasing filters, and can be use with long exposure times, filters, composition in visible, etc.
Contrary to poorly informed opinions, glass is not "opaque"to UV, but rather attenuates UV. Therefore, the more glass, the more likely the attenuation will be enough to make it appear opaque. Think now: If glass were opaque to UV, would you need UV filters to remove image haze from film or digital images? No, of course not! Many of the coatings on modern lenses attenuate UV more than the glass elements, and may actually approach real opacity. BTW, air also attenuates UV beyond what we call near-UV. Therefore, if you wish to do less expensive near-UV photography, and "see as the bees see" (never mind that this would be composite images, etc.) or at least obtain images that are reflected or are products of florescence in near-UV wave lengths (See, I'm sidestepping that silly argument.), then obtain an (or some) triplet or four elements lenses and if needed, thread adapters for your camera(s). There are still prime lenses from the 50s and 60s around on eBay and by other sources. You could use older enlarger lenses reversed. I have 50mm and 68mm Nikkor enlarger lenses. You could also consider quite early 50 or 52mm (58mm) lenses from Olympus in the f/ 1.2-1.8 range, those with white metal stop rings, as contrasted with later items with black rings. Less coating on these excellent earlier lenses. I suggest the faster lenses only because your exposure is going to be long, relative to visible spectrum photography. Forget the idea of punching a pinhole in a body cap to make a pinhole camera. The material is too thick. I think you'd have really ugly images and very long exposures. If you were to drill a much larger hole in the body cap and use black cement or black pigmented methyl cyanoacrylate adhesive, such as a particular black Locktite (spelling?), then you could have a fine pinhole (made before bonding, or punched against a suitable backing), then you could possibly have a pinhole camera. Of course, you'll still have some diffraction and a soft image. With respect to the Woods filters, perhaps you'd wish to experiment here, and find filters that attenuate at different wave lengths below 480nm, I think it is where visible spectrum falls off for those of us who've not had corneal implants.. BTW. if you have had such implants, you are probably familiar with the fact that the human brain processes near UV as essentially a repetition of the blue and violet visible bands. Yes, you see far red, red, orange, yellow, green, blue, violet, blue, violet. So, if you are digitally processing the images, and wish to combine images from near-UV with visible, then take the longer of the near UV, and process that as blue, and the shorter near-UV as violet. If those already exist on your image in the area of interest, then just choose something else, such as a contrasting color or high-contrast white. I have no suggestions about false imaging for the near-IR, except to pick a color that contrasts or suits your artistic proclivities. If you want to use multiple images from black/white film with different filters, and then process the scanned images for composite color, much as artists such as Larry Sanchez used to do with dye printing (not the correct term - a brain constipation is impacting the correct term), you can assemble whatever colors you wish from multiple images. Remember to use a tripod or sturdy stand, and be ultra-careful when you change filters. Perhaps you should make certain that your filter mounts are not leaking visible light into the camera before you invest too much into your subject photography. If you are going to use digital cameras, then if you can't afford to send your camera to a lab that removes IR and UV protective filters from the CCD or whatever detector, then maybe you could look for a used Nikon D-70, for it had a rep for having "crappy" ( I hear) or weak anti-aliasing filters, and Some have used the D-1, I hear. Both should be available at significantly reduced prices, for they have been superseded by better products with better technology for their targeted functions. I hope that I didn't inadvertently misstate something above, and that what I've said helps you find ways to make good UV and UV florescence photos.
A thought provoking business. It occurred to me that the whole 'transmittance of lens' issue would be resolved simply by using a pinhole camera. This would unambiguously be UV photography.
A simple solution for SLR owners would be to simply replace the lens with a body cap that has a small pinhole punched into it. A source of well filtered UV illumination would be useful to reduce the exposure times.
One could also achieve some very sharp photos above the diffraction limit, since the hole can be smaller than that used at visible wavelengths.
I've done regular photography similar in spirit to your work. Although I was mainly interested in UV luminescence, whereby UV light is turned into lower energy light - re-emitted at visible wavelengths. I found some interesting things in the woods, including a leaf stem that glowed under UV and squirrel urine that glowed intensely compared to water. The peculiar effects on regular items due to reflectance was also noted.
First on the question of optics, I tested several different optical systems for transmissivity . The test was done by shining my Flashlight O'Death through the optical system onto a fluorescent target, although I was unable to test the optical system of my camera this way, the optical system of my Canonette, a pair of "coated" binoculars and the disassembled lens system of a camcorder all showed strong transmission in the 390 nm region. Also three stacked "sky filters" caused no apparent diminishment in apparent fluorescence.
Second, specific to this camera, pictures of my FO'D show that my camera is sensitive to UV.
Third, on the use of wood's glass, a quick search shows that 18a filters were once called "wood's filters" because they're made from Wood's glass according to the MIT medical imaging website.
Finally, with a caveat, an image. The image shows three shots each of the same pink tabebuia. One is natural light, the pinkish one is illuminated by sunlight using my filter, and the third is illuminated by my FO'D at 390 nm. And on par, I think with Mr. Rorslett. So in conclusion, I do think this qualifies as UV photography, the caveat being that if your source of UV is the sun then there will be considerable IR "contamination".
http://www.naturfotograf.com/images/uvpoteere.jpg
As I previously stated, I believe there is more UV light in your photos than in a standard photograph, but it's still being washed out by the visible spectrum. While the images are likely UV "enhanced" they're mostly just magenta/blue.
That picture only proves that filters block their opposites and pass light of the same color. Causing the yellow to shift completely. Just like a red filter causes the sky to turn black in black & white photography.
If it is just a simple matter of yellow shifting to magenta should not the boundaries in this picture be coterminous? Sorry the flower moved I'll reshoot tomorrow if you insist.
Happy New Year to the nicest bunch of geeks in the world!
http://www.stagelights.com/color1.htm
Here's a lantana picture
the lantana taken with my wood's glass filter and the lantane taken with my secondary method
Seriously, next you'll be saying "That's not really an image, it's a bandpassed series of photons. If I can't see the radio waves in it, it's fake. And, it's taking a picture of the image formed by the lense! Terrible!"
This is taking a UV image. The way to tell is to try looking through the optics - if it is dark, then it is blocking the light you can normally see, and since your eyes are bad at UV (your corneas block it) even after your eyes adjust, you won't see much. If you then take that set-up, and use the rather higher UV transmission of your glass lenses, with a comparable exposure time, then it *has* to be UV that is making the film react, since we already know there is too little light coming through.
I'm looking forward to the butterfly pictures.
http://www.optical-filters.com/ug11.html
You should be able to find off-the-shelf UG11 filters for at least a 49mm filter fitting.
The lenses are very expensive because they should be using Calcium Fluoride and Fused Silica elements - both materials cost an awful lot more than the usual glasses used for lenses and designing an achromatic lens for UV/Visible is quite a challenge. Of course as someone already pointed out, you can use a Newtonian reflector.
If you're using film you need to check the manufacturer's website for the response to UV. Color film is generally bad and you will simply get bluish/purplish images - I'd recommend B/W because nothing else makes sense - if you want color then you need to use several UV filters and create your false color scheme, and doing all that makes the UV lenses look cheap.
If you're using a CCD they generally have poor UV response (but typically OK to 350nm) but there are 'coated' detectors which fluoresce to enhance UV sensitivity. CCDs have a good near IR response, so you may need an IR blocking filter which does not block the UV - there are some "dichroic" UV filters which would do that job nicely. UV + IR filter would get you a real UV photography filter for about ... oooh, no less than $600.
If you want genuine UV photography without paying too much, then stick to the UG11 glass (or similar) and a suitable B/W film. Ordinary lenses still transmit a bit around 350nm, but in any case you probably won't be metering correctly so you have to experiment to get your exposure times right and they could be as much as a few seconds. Since with a film camera you will see absolutely nothing through the filter, you also need to experiment and mark your lens to get the UV focus right. No matter how you look at it, proper UV photography takes a lot of time (and money). To help get the job done quicker (and guarantee good results) people do shuck out $$$.
I'm working with a friend at the moment and we're putting together a UV digital camera - total cost over $16,000 in parts.