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UltravioletPhotography

[SAFETY WARNING] UVC, UVB, UVA Monochrom Acorn Series


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SAFETY WARNING: 

UV-C is dangerous to your eyes and your skin.

UVP DOES NOT SUPPORT USING UV-C ILLUMINATION.

[UV SAFETY] UV-C Light Dangers


 

 

Warning, do not use 250nm UVC lights unless you take proper precautions. Image only in controlled room, away from pets, kids, loved and non loved ones. Best to image in dehumidified area, winter months work, to reduce air moisture. Ozone will build up quickly when working with UVc lights. Ideal to have a room vent. Tether your camera to a computer located in an other room to work with camera settings and images. Thus can be done with 25 feet long usb cords.

 

 

Andy requested a fun series of UVC, UVB and UVA images. So I photographed an Acorn yesterday next my dried up Kiwi berries, that I imaged last week and still need to sort.

 

This was imaged differently. Here I am using the 60mm f3.5 KSS quartz lens set at F4 on the phosphor imager. I have then converted the back with a set ring to mount my Olympus 30mm Macro lens which is set at F5.6 on my Panasonic GM5 camera (stock not converted). The camera was set to ISO 200 and all photos were taken in Monochrome mode as the back imager is just green anyway, so might as well be monochrome.

 

For the 253nm UVC images a 250nm UVC sterilizing bulb was used.

253.7bp25 only:

post-188-0-85428300-1575401508.jpg

 

 

For all the rest of these images a single UVB ExoTerra 26W bulb was used.

303bp10 + 330Wb80 improved:

post-188-0-12991700-1575401645.jpg

 

313bp25 +330Wb80 improved:

post-188-0-40752300-1575401660.jpg

 

335bp10 + 330Wb80 improved:

post-188-0-63684900-1575401678.jpg

 

340bp10 + 330Wb80 improved:

post-188-0-77602000-1575401694.jpg

 

370bp15 + 330Wb80 improved:

post-188-0-20505300-1575401709.jpg

 

390bp25 only:

post-188-0-11507900-1575401728.jpg

 

Now for the fun part you can do this a home as well. I aligned the images using hugin and then color stacked them using Gimp in the color compose tools.

These are my fun ones to compare:

 

254R_303G_370B

post-188-0-57113300-1575401959.jpg

 

254R_313G_370B

post-188-0-45300500-1575401974.jpg

 

254R_335G_390B

post-188-0-68639000-1575401993.jpg

 

303R_370G_390B

post-188-0-44734200-1575402009.jpg

 

313R_370G_390B

post-188-0-53703100-1575402025.jpg

 

335R_370G_390B:

post-188-0-95755800-1575402039.jpg

 

There is almost no change in the dried fruit, but the color composite allows you to really see the differences in the Acorn. I will have to get some flowers or test this better with some fruits.

 

A color image of the test acorn for comparison with GM5 Olympus 30mm at F8 ISO200:

post-188-0-55551500-1575402969.jpg

 

Filter information updated to all stacked filters used.

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Ooh nice! Yes, I like this. You can see some real color differences when you use a wide enough spectral band.

 

Why are the longer wavelengths fuzzy? Is that entirely diffraction?

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I had to refocus for each filter change. then when I changed the bulb for the UVC image which I took last I knocked it slightly so the view is slightly different.

 

I think some are fussy as I just don't have the same focus point. The 390 seems to be more front focused.

 

What I think is really interesting is that band mid Acorn is not strickingly clear in the normal visible. But in the UV color merge files you can clearly see the upper UV or violet (390) region. Some detail more striking in UV. Also I don't really see this in the Monochrome only images. The color composites really help.

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What filter are you using for the 253 image?

I'm pretty sure it's just the one that came with the Sirchie scope. (It's designed for UVC, so there is no doubt in this case that that is what is being observed.)

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Wait and see what he says I guess.

Keep in mind that UVC lights have a huge amount of UVB, UVA and Visual Violet emitted, furthermore, UVC lights have a short UVC emission lifespan. They continue to emit other wavelengths of UV and visual practically forever, beyond the time they stop emitting UVC. This is not really the point, the point is that thy do have a wide emission band.

One would need to filter photos using them to within a narrow UVC range.

Without knowing that range of that filtration I can not begin to interpret that UVC photo.

 

That link doesn't answer my question, butthank you for that link, Andy, I have not seen that before.

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I have the same one, and regardless of the details of exactly what range of UVC is being transmitted, I do not see how the Sirchie can accomplish its intended purpose of showing fingerprints if the photos it produces are not really UVC. This is not an amateur setup. It's a purpose-designed device.
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To answer my question, I am going to need details, some specifications, but they are not on that page.

The only pertinent info there is that it has UVC lights.

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eye4invisible

Sorry, I'm a little confused here.

 

I was under the belief that UVC only transmits in a vacuum, so did you have your setup remotely controlled in a vacuum chamber?

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UVC is used to steralize water, air... so not just a vacuums.

Doesn't this device have a user manual? Perhaps the manual has the answer to my question in it? Specifications.

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I was under the belief that UVC only transmits in a vacuum, so did you have your setup remotely controlled in a vacuum chamber?

Not quite - it will go short distances in air, but not long distances. Like a few feet of air, but not a few miles.

 

Doesn't this device have a user manual? Perhaps the manual has the answer to my question in it? Specification.

I'm sure the original did, but we got ours from that eBay auction that Jonathan linked.

https://www.ultravio...rimesite__st__0

 

Particularly see the blocking tests that David did here:

https://www.ultravio...dpost__p__29008

 

ETA:

Here is the manual, but it doesn't have any additional info on blocking, just that it's "254nm peak with 25nm (full width at half maximum) bandwidth typical".

https://www.manualslib.com/manual/1386446/Sirchie-Krimesite-Kss60.html?page=6#manual

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The best I could find is the word "shortwave" UV light in a YouTube.

 

A shortwave filter can be a lot of things, but unless it is defined then we don't know all of what it is transmitting.

You should really ask the company what the transmission graph looks like for the shortwave filter they use in the device.

I am sure it works well for what it is designed to be used for, but this may not be exactly what it is being used for here.

I would want to know specifically what the filter transmission is before assuming you are only recording something close to 253nm.

"Short wave" could mean different things..

For example, a UG5 filter transmits shortwave 250nm UVC @ 70%.

Without knowing the transmission graph of the filter used in the device you can't define the transmission.

 

Find the specifications.

 

Also, I might add, the way in which they are using the UVC lights in the demonstration they show in the videos seems a little bit dangerous.

They are wearing UV protective eye-wear, but they are not completely covered, I see some exposed skin, and that is just extremely bad to do around UVC,

even regular clothing is not enough to stop UVC.

DO NOT play around with UVC lights unless you are in a different room or wearing head to toe welding gear.

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Cadmium I listed them above. David did stacking tests also which I linked. I don’t have any more information but I think your skepticism is not warranted here. When stacked with 330Wb80 you get black images. Etc.
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Wow how interesting, it must have taken you a long time to do this ?

Col

 

Actually no. This series was the fastest I have ever shot a UV series in my life. That is the advantage of the phosphor imager in the device.

 

I set up the scene to test my Lodestar sensor for UVc response. It can capture with this filter but focusing again is the biggest pain. I had 60mm Macro with 253nm filter directly on the camera and needed 60 to 90 seconds of exposure. So to focus it would have taken 1 to 2 hours to nail. Then I though lets prefocus on the imager.

The response is very quick. So then I just switched over to it and attached my camera.

These images are all less than 1/2 seconds except for the 303bp10 filter shot that needed 1 second as little 302nm line comes off the UVb ExoTerra light.

So actually very quick and may continue to do this over using the camera directly.

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Sorry, I'm a little confused here.

 

I was under the belief that UVC only transmits in a vacuum, so did you have your setup remotely controlled in a vacuum chamber?

 

No moisture and oxygen kills UVc transmission. So after a while the ozone smell gets quite intense. I would say more dangerous than the UVC light.

 

I am about 12 to 18 inches from my subject.

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Not quite - it will go short distances in air, but not long distances. Like a few feet of air, but not a few miles.

 

 

I'm sure the original did, but we got ours from that eBay auction that Jonathan linked.

https://www.ultravio...rimesite__st__0

 

Particularly see the blocking tests that David did here:

https://www.ultravio...dpost__p__29008

 

ETA:

Here is the manual, but it doesn't have any additional info on blocking, just that it's "254nm peak with 25nm (full width at half maximum) bandwidth typical".

https://www.manualslib.com/manual/1386446/Sirchie-Krimesite-Kss60.html?page=6#manual

 

Cadmium this is the same 253bp25 filter Andy and Jonathan have. I look forward to Jonathan's test report on it in January.

My filter from my tests is the best IR blocking I have seen. Worth the price of the lens and imager for almost free. Its only 25mm round. Its custom for the imaging system which is really intended to be used to look at fingerprints after superglue trick.

The link above I have the broucher, which doesn't say much really. Thus why I call it a KSS lens as Jonathan recently found out its a copy of the Resolve 60mm f3.5, not a Resolve 60mm lens. Maybe issues around that for why these systems were liquidated cheap on ebay.

The light is a germicidal 254nm mercury quartz tube that you can buy for very cheap.

I talked about it before.

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There is this image from the link you suggest, which I am not clear on.

The image says it is UV filtered. I don't know what UV filter that is referring to, and I see some small amount of blue in the lower left.

That image is with halogen light.

https://www.ultravio...-1564472117.jpg

 

can you explain the blue in that image?

That test is the filter removed, placed on the lens and imaged with a hallogen lamp (which as you know has a ton more IR than UV) the crank the exposure up to 1600 ISo and image for 60 seconds.

My images above are off the back of a green phosphor screen which is only responsive to UV. No response at all to IR. I have tested it. You also can't image visible light off the imager either. So you have to dismount the camera.

The 253nm shot off the back imager is iso 200 f5.6 for faster than a half second. I will have to check exact settings.

 

When filter is directly on a camera I need more than 60 seconds, its possible, but not practical as focusing is near impossible. The Lodestar x2c 829 CCD 752x580 sensor with GCMY color filter is sensitive to deep UV. But real pain to focus and you need special Astrophotography software.

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Yeah, if there is a leak, a blue light leak is the most likely here. I have not tried imaging anything at UVC and I don't own a UVC light source. I'm frankly rather wary of UVC and ozone, which is a nasty pollutant. If I start dabbling in UVC imaging, my plan would be to construct some kind of light-tight box to do the experiment inside of.
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I see, so the halogen could have enough 250nm emission to be seen at that exposure. So this doesn't mean the blue is UVA.

 

I was not suggesting that the filter could be UG5, given the Red/IR transmission of UG5, it was only an example, just that the filter could possibly be transmitting above whatever point, even into UVA as well as UVC,

in other words that the range could be wider than only UVC.

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