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ArcticMyst Security by Avery

Starting UV and IR Photography; Equipment Search and More!

Joined
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Cool - now do one with sunscreen

Yup, that's certainly on the to do list next time I get free time on a sunny day. It amazed me how much more UVA there is in sunlight than in "high UV output" lamps. 400W of UV lamps is nothing compared to even a mostly cloudy day. Also, I'll have to pick up some organic sunscreen, all I have are TiO2 which is UV reflective.
 





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It amazed me how much more UVA there is in sunlight than in "high UV output" lamps

Well yeah. Visible light also is a couple orders of magnitude higher outside than inside, even with 400W HID lamps. We just don't notice much because of iris, etc.
 
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I haven't gotten around to processing the UV shots yet, but here are a few of the NIR and IR ones from my 17-4-15 shoot. Some images have a central hotspot because I had so much sun on the screen at time of shoot I couldn't see it to correct for it.

NIR are false colorized and are 640-1200nm. The B&W shots are 850-1500nm.

fCD5VOB.jpg


6gIvaA0.jpg


8cJPys5.jpg


Vk5259B.jpg


CcxqVOW.jpg


Swsq2DG.jpg


When I get some time I'll process and post the UV shots, they're really MUCH better. It really shows the difference between $10 IR filters and $200 UV filters, haha. You really do get what you pay for.

Edit: It also appears that Imgur's resize function has butchered the quality. If anyone wants a highres version just request it. These are 12MP JPGs which run about ~7MB each.
 
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Hi Sigurthr,
Very nice shots! I like the last one the best. Nice dark sky and white tree makes for a nice contrast. I have played around with the false color, and at least for me, like the B&W ones the best. I took some IR shots today and will probably get a few of them posted in the next few days . Looking forward to seeing your UV shots when you get to them.
 
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Neat :) Those look really eerily entrancing. Wouldn't it be weird if the sky was black, but everything was still lit? :0
 
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joeyss

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I have a 200 dollar lens for my dslr that lets uv in but my issue is it leaks some small amounts of IR in. It totally rejects visible light and even 400mw of 405nm is blocked. The only light that gets through is my 85W hid at 8000k. Should I just turn the red and green balance to low with magic lantern? Turning the blue and green to low worked for ir photos. It got rid of the pinkish hue and the sky looked alot darker. Ir shows up red on my DSLR so I think lowering the red sensitivity would work for the UV one.
 
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I have a 200 dollar lens for my dslr that lets uv in but my issue is it leaks some small amounts of IR in. It totally rejects visible light and even 400mw of 405nm is blocked. The only light that gets through is my 85W hid at 8000k. Should I just turn the red and green balance to low with magic lantern? Turning the blue and green to low worked for ir photos. It got rid of the pinkish hue and the sky looked alot darker. Ir shows up red on my DSLR so I think lowering the red sensitivity would work for the UV one.

Digital editing won't work because the order of magnitudes are very far apart. However, you can use a special IR block UV pass filter to correct this issue without hassle. Look for a Schott S8612 in 2mm or 2.5mm thickness. On eBay you can get it easily; search auction 291435326092
 

joeyss

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I know coke is clear in IR is there anything I can use to test UV out in my room?
I have a UVA blacklight and a uv-c lamp with some uvb in it ( yes I know to wear protection) There has to be something that's clear at normal wl and not at say 370nm right?
 
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I know coke is clear in IR is there anything I can use to test UV out in my room?
I have a UVA blacklight and a uv-c lamp with some uvb in it ( yes I know to wear protection) There has to be something that's clear at normal wl and not at say 370nm right?

See my previous posts. Regular old safety glasses are clear to visible but black to UV. Any polycarbonate does this.
 

joeyss

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See my previous posts. Regular old safety glasses are clear to visible but black to UV. Any polycarbonate does this.

The googles I work with are orange laser ones but I do have some clear lab goggles.

It's dark I think i'm gonna test it. in my room.
 
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Yesterday I took some of my best ever NIR/IR shots: (False Color, B&R Channel Swap, custom WB, WB tweak in post)

9emYXO1.jpg


zzURmIR.jpg


TxiXMSV.jpg


m2lPM85.jpg


I also took some of my worst VIS-only shots. Apparently the cheap IR-UV-Cut Hot Mirror (not the $100 one (S8612) I use with my U360 for UV-only) can't tolerate above 45degrees Angle of View (AoV). Accurate color in the center and then a massive chromatic distortion vignette with everything green shifted. So, I either have to consider separating my expensive, fragile, and hard to replace UV-Only filter stack to use the S8612 when I want VIS-only shots, or stick to >24mm FL. I think I could get away with just using a heavily stopped aperture, perhaps F11 or more, but I'll have to test it. It's a shame because two of the shots would have been killer. I can convert them to B&W to salvage but it's not the same.
 
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Beautiful shots. The first one is my favorite. The golden color of the trees contrast very nicely with the white clouds and blue sky.
 
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I did my own modifications on old P&S cameras following the "Hiro sandwich" guide mentioned here. It involved using microscope slides and some optical glue (Entellan® new, about $65 with shipping) and microscope slides (I got standard 1.2mm and some 'special' 1.0mm ones). The IR/UV pass window has to have roughly the same thickness otherwise the camera can't focus, and the thickness of the window I needed at the time (Powershot G3) was about 2.2mm. It worked great and I could even film with the camera if I wanted with the 720nm and 930nm filters.

The 50ml of glue and microscope slides should be enough to create a lifetime worth of IR camera mods, but unfortunately the cut windows are much thinner these days -- thinner than even a microscope slide. I later tried to modify a Powershot G9 to no avail. The cut filter was really thin, like 0.5mm or 0.3mm or something. Coverslips are also useless because they're designed for wet material; they're always stacked up and scratch the surfaces of each other.

Older P&S cameras should still work though. I have yet to attempt it on a Powershot G6 I have sitting on a shelf. That model is unfortunately too old to use CHDK though, but even then it should be a nice camera for infrared. They're relatively cheap too, so it should fit within a $300 budget. There was a pre-modded on on eBay for about $300 too, but only UV or IR, not both.

If I were to buy a camera for IR/UV, I'd probably go for a Canon EOS M and have Lifepixel install a clear window. They're mirrorless cameras that are pretty cheap ($330 w/lens). It was originally a $800 camera, but Canon screwed up their firmware and it had horrible focus speed so it got dumped. They eventually fixed the firmware for decent focus speed and it's a huge bargain now. Get the oldest model because it's the same as the revision after; the revision just fixes the firmware.

The nice thing about the Canon EOS M is that it is purely a LCD-based camera. This is useful because you can't see anything with a DSLR that doesn't have live-view. Furthermore, there is a full APS-C sensor in the EOS-M, the same one in their cheaper DSLR lines. You can also manually focus the lenses, so if things look off you can compensate.
 
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Excellent, BB! Yeah, Lifepixel or MaxMax is the way to go (MM will de-bayer the sensor too, which is a HUGE boost for UV work, but will render the camera B&W only). I tried converting my old Easyshare P&S but it used a sensor which had the ICF epoxied to it, so I couldn't remove it. It was a terrible camera anyway, wouldn't have been much use.

Mirrorless has the advantage of a single optical path with LCD-centric operation (better ones have electronic viewfinders which suffer no detriment like DSLR optical viewfinders do) and work exceptionally well for multispectral photography.
 




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