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Not been able to post much for a while (mix of work, computer and broadband issues and family) but wanted to shared this. I have enjoyed reading the posts though, so thank you all for that. Finding reliable fluorescence standards which don't cost the earth has been something that was lurking at the back of my mind for a while. Browsing the Thorlabs site I came across some microscope slide shaped fluorescence standards which were surprisingly cheap - 5 different colours for about 20USD. In fact shipping cost me more than the filters did. Here's the link to the slides - https://www.thorlabs...partnumber=FSK5 Thorlabs do give fluorescence graphs for these, but they did not always use UV as the illuminant. I've been wondering whether there is a wavelength shift in the emission spectra from these types of standards if different wavelengths of UV were used to illuminate them, or whether they were relatively consistent. Manufacturers of fluorescence standards often say things like - to be used with 365nm illumination - but of course we have different light sources with different spectral characteristics. Below are some results of initial testing to look at this. Basic setup for the experiments - fluorescence standards placed in a cardboard box painted with Semple Black 3.0 paint (low fluorescence and reflectance). Experiments run in a dark room. Light sources - Hamamatsu LC8 200W Xe lamp with a UV collimator lens and a Nemo 365nm torch. Filters for the light sources - Baader U, Edmund Optics 310nm, 320nm, 330nm (BP 10nm) and Thorlabs 340nm, 350nm, 360nm, 370nm, 380nm and 390nm (bp 10nm) filters. Camera - unmodified Canon EOS 5DSR with Rayfact 105mm UV lens (at f8) with a 420nm longpass filter from Klaus which has very low fluorescence. ISO 400. Images captured as JPEG in the camera - with a Daylight Whitebalance setting (no auto whitebalance, and everything done with the same setting). Exposure time either 1/4s or 1s as shown in the images. I used the Rayfact lens as it is nice and sharp and has a 52mm filter thread on the front to match my 420nm long pass filter. Quick image of the setup. Fluorescence of the slides using the 200W Xe lamp filtered with a Baader U filter (f8, ISO400). With the broad UV source, as expected a nice range of fluorescence colours from the slides. Next a Nemo 365nm torch filtered with a Baader U, shown with 1/4s and 1s exposure time. The 365nm torch also gave a good range of fluorescence, although the second slide from the left (the Green FSK2 one) seems to be much more fluorescent than the others when the Nemo with its strong 365nm line was used. As the final test it was back to the Hamamatsu Xe lamp again in combination with 310nm to 390nm bandpass filters. This time exposure was 1s for the images. Now obviously there is a variation in the intensity of the light source between 310nm and 390nm and the filters have different max transmission values, which will have an impact on the degree of fluorescence occuring. It is interesting to note that there is a wavelength dependence on the degree of fluorescence from each filter - the relative brightness of each one is the not the same for all illuminant wavelengths. But, visually at least, there does not look to be much of a variation in the fluorescence colour of each filter at the different UV wavelengths. Ideally I'd like the measure the fluorescence emission spectra of each slide at each wavelength, but I'm not really setup for that. Overall, very impressed with the Thorlabs fluorescence slides, especially given their price, and they should be a good options when looking for standards to help when imaging UV induced fluorescence.

So, slowly ticking off a few indoor-things on my to-do list before the summer season fully kicks in, I've turned my attention to a painting which I've wanted to take photos of for some time. I bought the harbour-painting years ago at a discount when a local art shop went bust; must have been at some point during the 1990's. According to this article, it's a fake: https://www.walesonl...ns-most-2080619 (apparently, the artist only signs on the back of the paintings), so I won't be able to sell it and retire on the proceeds The second painting (the one with the ship-wreck), however, is genuine, as I purchased it directly from the artist The equipment used is as follows: VIS: Canon, EOS 5DSR, Canon EF 24-70mm UV1: Canon EOS 6D, b/w-conversion, internal X330C, external S8612, Steinheil München Cassar-S 50mm UV2: Canon EOS 6D, full spectrum, UV-filter by Optik Macario, Steinheil München Cassar-S 50mm IR: Canon EOS 6D, converted to 700 nm, Canon EF 24-70mm Post was minimal, mainly cropping (which made me realise that I hadn't aligned the sensor fully parallel to the paintings). The shots with the LEDs display some uneven lighting, which is due to my wobbly handling of the torches. That's why I took the control shots with the full frontal FS-flash. I. Harbour (whoever painted this) 1. Visible light, room-lights 2. Visible light, UV-LED (Nemo) 3. IR, room-lights, WB grass 4. IR, 850nm-LED, WB same as 3 5. IR, 940nm-LED, WB same as 3 6. IR, UV-LED (Nemo) 7. UV1, UV-LED (Nemo), light-painting, standing slightly to the left of the camera 8. UV1, FS-Flash (Yongnuo YN560-III), flash held over the camera, pointed directly at the canvas 9. UV2, FS-Flash (Yongnuo YN560-III), flash held over the camera, pointed directly at the canvas, WB in-camera from PFTE 10. same as 9, converted to b/w in Lightroom II. Shipwreck (Romana Rachbauer) 1. Visible light, room-lights 2. Visible light, UV-LED (Nemo) 3. IR, room-lights, WB grass 4. IR, 850nm-LED, WB same as 3 5. IR, 940nm-LED, WB same as 3 6. IR, UV-LED (Nemo) 7. UV1, UV-LED (Nemo), light-painting, standing slightly to the left of the camera 8. UV1, FS-Flash (Yongnuo YN560-III), flash held over the camera, pointed directly at the canvas 9. UV2, FS-Flash (Yongnuo YN560-III), flash held over the camera, pointed directly at the canvas, WB in-camera from PFTE 10. same as 9, converted to b/w in Lightroom

Nikon UK have kindly lent me a Z7 II for a couple of weeks to help with a new book I am writing. I thought I would try out it's Focus Shift mode (focus stacking) with a UVF image of a carnivorous plant (Nepenthes lowii x N.ventricosa). Being a confirmed DSLR user it has taken me some time to get to grips with the viewfinder and other electronic features of the camera, most of which I have turned off! The sequence was put together in Photoshop. The pitcher is approx. 3cm in width. The uneven lighting on the UVF image is due to the fact that you can't light paint a focus stacked image, so the torches were held in clamps. I held my breath during the sequence! Technical specs: Visible light: Nikon Z7II with 105mm micro Nikkor. Studio flash, f/16, 200ISO UVF: camera/lens as above. Two Convoy S2+ UV torches. 10 images, each 1 second @ f/5.6

I just received 2 of theses camera I am about to test awaiting adopters to mount a a F mount lens and able to mount to telescope too. I have costal 105mm uv lenses a uka UV 25mm cmount lens and a keyoei and clones and also microscope objectives and so on.... they are going to be fun to play with full monochrome full frame cameras..... Apogee Alta U9000X link to camera specs: http://www.telescope.../pdf/U9000X.pdf c&p The Alta U9000X uses a very large format 9-megapixel full frame sensor with anti-blooming gates, ideal for applications requiring large field of view, such as astrophotography, sky surveys, and radiology. The X version has a 16-bit digitization rate of 1.8 megapixels/second, compared to the 1 MHz for the U9000. • 3056 x 3056 array, 12 x12 micron pixels • 5 MHz 12-bit and 1.8 MHz 16-bit digitization • 32Mbyte camera memory • USB 2.0 interface: no plug in cards or external controllers • Programmable, intelligent cooling to 40°C below ambient • Binning up to 8 Horizontal x 3056 Vertical • Subarray readout and fast sequencing modes • Precision time delayed integration (TDI) and kinetics mode readout • Programmable fan speed for low / zero vibration • Two serial port outputs for control of peripheral devices • General purpose programmable I/O port • External triggering and strobe controls • ActiveX drivers included with every system • Field upgradeable firmware • Fused silica windows • Runs from single 12V supply with input voltage monitor • Compact enclosure • Programmable status indicators CCDSPECIFICATIONS • Astronomy • Radiology • Optical testing • Non-destructive testing HighPerformanceCooledCCDCameraSystem ALTA U9000Xblob:https://www.ultravioletphotography.com/be38c4f3-bb0f-4723-ab1a-9b4477bf188d Imaging Area of CCDblob:https://www.ultravioletphotography.com/55730472-6855-43c1-b57d-0ea464509927 blob:https://www.ultravioletphotography.com/4677f478-a692-4a96-8e6f-41aba68d54f1 blob:https://www.ultravioletphotography.com/30a1ea90-ade4-4225-a1b8-48c4c4ebff81 blob:https://www.ultravioletphotography.com/f6ac8431-f1f9-4c1c-9c69-f24ea3ad8dea CCD Array Size (pixels) Pixel Size Imaging Area Imaging Diagonal Video Imager Size Linear Full Well (typical) Dynamic Range QE at 400 nm Peak QE (550 nm) Anti-blooming Kodak KAF-09000 3056 x 3056 12 x 12 microns 36.7 x 36.7 mm (1345 mm2) 51.9 mm 3.24” 110K electrons 84 dB 37% 64% For complete CCD specifications, including cosmetic grading, see data sheet from manufacturer. PC Interface Max. Cable Length Digital Resolution System Noise (typical) Pixel Binning Exposure Time Image Sequencing Frame Sizes Cooling (typical) Dark Current (typical) Temperature Stability Camera Head Size Mounting Back Focal Distance Operating Environment Cable Length Power Shutter Remote Triggering USB 2.0 5 meters between hubs; 5 hubs maximum (max. total of 30m) 16 bits at 1.8 MHz and 12 bits at 5 MHz 10 e- RMS at 1.8 MHz and 2 counts at 5 MHz 1x1 to 8x3058 on-chip 30 milliseconds to 183 minutes (2.56 microsecond increments) 1 to 65535 image sequences under software control Full frame, subframe, focus mode Thermoelectric cooler with forced air. Maximum cooling 40°C below ambient temperature 0.3 e-/pixel/sec (-20°C) ± 0.1°C D7. Aluminum, hard blue anodized. 7” x 7” x 2.55” (17.8 x 17.8 x 6.48 cm) Weight: 4.2 lb. (1.9 kg) 5,125” bolt circle. Optional Nikon F-mount or Canon FD mount. 1.008” (25.60 mm) [optical] -22° to 27°C. Relative humidity: 10 to 90% non-condensing. Standard: 15 ft (4.5m) 40W maximum power with shutter open and cooling maximum. AC/DC “brick” supply with int’l AC input plug (100-240V, 50-60 Hz). Alternate 12V input from user’s source. Melles Griot 63mm. LVTTL input allows exposure to start within 25 microseconds of rising edge of trigger

I took advantage of the long winter nights to do some fluorescence photography. Here are some results of UV- and Visible-Induced IR fluorescence, done in tri-colour. I’ve also included standard visible and a few UVIVF images for comparison. (There are some more tri-colour IR Fluorescence images, using rock samples at https://www.ultravio...__fromsearch__1 ) The Tricolour channel assignments are: Red Channel: 1000nm Green Channel: 850nm Blue Channel: 750nm Light Sources: UV: Nemo Torch Visible: Lumitact LED torch. Narrower-band Excitation My available UV light sources and filters did not allow for excitation using a narrower band of the UV spectrum, but this was possible using visible light. This set of images includes Visible-Induced IR Fluorescence excited by white, blue (470nm), green (520nm), and red (635nm). Apart from colour cast, there is not a lot of difference, and so all later Visible-induced IR Flourescence images use just white excitation. The blue and red colour casts on the blue- and red-excited images cannot be due to any form of blue or red visible light leak: blue and red in the image is caused by transmission through 750nm and 1000nm bandpass filters and there is no reason why blue light would leak only through the 750nm filter and red light would leak only through the 1000nm filter. Orchid: Visible..........................................................................UV-Induced Visible Fluorescence UV-Induced IR Fluorescence Visible (White)-induced IR Fluorecence......................Visible (Blue)-induced IR Fluorescence Visible (Green)-induced IR Fluorecence.....................Visible (Red)-induced IR Fluorescence White Balancing How do you white balance images like this? I started off with using WB based on a white section of a rock, but this often just gave visually uninteresting so I started WBing against elements of the image. This example shows the differences this can produce. Lily Visible....................................................................................................................UV-Induced Visible Fluorescence Visible-Induced IR Fluorescence: Rock WB method:..................................................................................................WB against dark area at top-left: WB against leaf: UV-Induced IR Fluorescence: WB against leaf: Forsythia: Visible: UV-Induced IR Fluorescence:................................................................................Visible-Induced IR Fluorescence: Flaming Katy: Visible:..................................................................................................................UV-Induced Visible Fluorescence: UV-Induced IR Fluorescence:...............................................................................Visible-Induced IR Fluorescence: For both of these images, saturation has been increased and WB was against the leaf. Winter Aconite: Visible: UV-Induced IR Fluorescence:...............................................................................Visible-Induced IR Fluorescence: Chrysanthemum: Visible: UV-Induced IR Fluorescence:.................................................................................Visible-Induced IR Fluorescence: Visible:...................................................................................................................UV-Induced IR Fluorescence: Jasmine: Visible: UV-Induced IR Fluorescence:................................................................................Visible-Induced IR Fluorescence: WB was against the stamen tip. Snowdrop: UV-induced Visual Fluorescence:.........................................................................Visible-Induced IR Fluorescence: These imges were WBed on the light part of the petals. Daffodil: Visible:..................................................................................................................UV-Induced Visible Fluorescence: UV-Induced IR Fluorescence:...............................................................................Visible-Induced IR Fluorescence: WB was against the stigma tip Tulip: Visible :...............................................................................................................UV-Induced Visible Fluorescence: UV-Induced IR Fluorescence:.............................................................................Visible-Induced IR Fluorescence: These last two images were WBed on the stigma. And now something completely different – Sugar Cubes: Visible:..............................................................................................................UV-Induced Visible Fluorescence: UV-Induced IR Fluorescence:...........................................................................Visible-Induced IR Fluorescence:

This is a visible light/UVF pair of a fossil shrimp: Carpopoenaeus callirostris, from Lebanon (Upper Cretaceous, 99 - 93 myo). The UVF images shows some interesting extra detail such as legs etc. Technical details: UVF: Nikon D850, with 105mm micro Nikkor. UVF image: 10 seconds @ f/16, 200 ISO, NEMO torch - light painted.

Found these lying around from last year. Painted with the convoy S2 contender F14, iso100, 15sec, 105mm micro Nikon

Today I chanced across my old, failed harddrive, which I had set aside in order to take some photos, and decided to give it a go. I used my usual cameras: VIS: Canon EOS 5DSR IR: Canon EOS 6D, converted to 700 nm FS+UV: Canon EOS 6D, converted to full-spectrum As lens I used the EL-Nikkor 80mm f/5.6, set at f/16 throughout. Most of the photos are at ISO 100, only the UVIIRF is at ISO 800, and the UV with UV-LED is at ISO 200. For the UVIIRF I still had to use 30s as exposure time. As is evident from the shadows, I didn't put the torches or the flash on a tripod but handheld them, so the angles are not completely the same, which I don't expect to make any real differences. What do you think? I find it interesting how the circuit paths appear and disappear, and I'll definitely have to check out the glowing bits in the UVIIRF. First, VIS-camera, room lights (Standard Osram LEDs with 2700 K) for lighting: Next, VIS-camera, Nemo-torch (365nm): : FS-camera, without filters, room-lighting (Standard Osram LEDs with 2700 K): FS-camera, without filters, full-spectrum flash (Yongnuo VN560III with the cover removed): FS-camera, without filters, Nemo-torch (365nm): FS-camera, UV-filter by Makario, full-spectrum flash(Yongnuo VN560III with the cover removed): FS-camera, UV-filter by Makario, Nemo-torch (365nm): IR-camera, room-lighting (Standard Osram LEDs with 2700 K): IR-camera, full-spectrum flash (Yongnuo VN560III with the cover removed): IR-camera, Nemo-torch (365nm): IR-camera, LED-torch 850nm: IR-camera, LED-torch 940nm:

Hi there! I am Shamali from India. I am a botanist and just entering the field of UV photography. I aim to work on UV reflectance of flowers. I use a Sony a6000 camera. But I think will have to get a conversion done for UV photography. Your guidance would help in understanding the basics. Thanks..

Hello Everyone, I'm in Yorkshire and I hope to learn more about UVIVF and perhaps apply it to my other interests of Land(Night)scape, Portrait and Macro photography. I have not done any UVIVF at all so far, I will make a separate post with a few equipment questions. Jon.

Baby Steps, as I re-learning photography after a 6 year break, using improvised lights. One rock, three lights. Blue Sodalite under White light 6000k. Blue Sodalite under UVC 254nm, UVIVF. Blue Sodalite under UVA 365nm, UVIVF.

This is infrared photography in the 720+ nm range. Author's technique of shooting. Converted Nikon 7100. Matrix Toshiba HEZ1 TOS-5105. Spectrosil 2000 matrix filter. SCHOTT RG-9 camera filter by Uviroptics Lab. Many thanks for this filter! [upd. Sorry, my forum photo uploader still doesn't work.]

I searched through the forums for this, as well as searching for the URL at which the product is located, so seems like no one has shared this before. I figured I'd bring it to everyone's attention. It only has RGB and GBW squares, and costs a whopping $875 (US dollars) though. http://www.imagescienceassociates.com/mm5/merchant.mvc?Screen=PROD&Store_Code=ISA001&Product_Code=TUVUVGC&Category_Code=TARGETS

In the post at https://www.ultravio...-your-rocks-of/ I showed results of fluorescence exhibited by some rock samples using both UV (Nemo torch) and visible excitation. The subsequent comments raised the idea of using a low-cost 254nm UVC lamp to see if that gave different output. So I got myself one of these rom China: https://www.ebay.co....872.m2749.l2649 . A few weeks later it arrived – but the filter was chipped along the edge and leaking light, and the filter housing wouldn’t close properly. The supplier said something like “Yes, happens all the time. But it will be OK.” Anyway, they sent me a new filter, which I cemented to the outside of the housing, and off we go. Health warning: UVC is dangerous. There’s plenty of advice on the forum about protecting yourself using glasses, cotton clothing, etc. In addition I took two precautions: Adapted the lamp to run off external power and used the cameras on WiFi remote control, to let me operate from a different room. As the lamp needed several minutes to fully “warm up” it was impracticable to turn the lamp off between each shot. So I made a simple cardboard sleeve to slide over the lamp so I could work nearby to set up the camera and target. UV and IR Colour Images: In UV and IR false-colour images below, the following colour assignments have been used: Red Channel UV: 380nm Green Channel UV: 345nm Blue Channel UV: 315nm Red Channel IR: 1000nm Green Channel IR: 850nm Blue Channel IR: 750nm The lamp: It became clear that the lamp and its filter leak a lot of non-254nm wavelengths. I tried to get fluorescence output at UVA wavelengths, but the images were almost entirely like reflected light images, although there was a hint of fluorescence output – results later. More surprisingly, there was a lot of IR leakage too. The IR output results looked totally like reflected light images with no hint of fluorescence. I have not bothered to post any results here. Fortunately the visible output was reasonably good – but the fluorescence is being excited by multiple wavelengths, not pure 254nm. The following images give an idea of the leakage. In each case, the upper image used exposure similar to that used to make the fluorescence images, and the lower image is at a lower exposure to show the colour of the leakage. The colour images were WB-ed for sunlight. Visible Output: UV Output: IR Output: I also used one of Stefano’s tests (see https://www.ultravio...-265-nm-uvc-led ) to judge how strong the 254nm lamp output was. Pure 254nm (or at least below about 320nm) would render the magnifying glass as pure black. My conclusion is that there is a lot of 254nm, but there are longer wavelengths as well. In each case, the upper image is against paper (fluorescing) and the lower image against PTFE (probably non-fluorescing). Visible: UV (lower image's exposure was 7.5x upper image's exposure): IR: Results 254nm-Induced Visible Fluorescence When looking at output in the visible range, some targets look the same whether excited using the Nemo torch or the 254nm lamp. But in some cases there was some additional green fluorescence. The top images are normal visible images, the middle images are UVIVF made using the Nemo torch, and the lower images are UVIVF made using the 254nm lamp. Rainbow Flourite I assume the fluorite is the main bulk of the sample, and the white/green areas are something else adhering to the fluorite. So the fluorite fluoresces consistently blue, but the “something else” shows green under 254nm. Group 3 What’s really noticeable here is the appearance of green in the Aragonite and yellow calcite, and the whitish fluorescence in the blue calcite (bottom left). 254nm-Induced UVA Fluorescence: As mentioned above, these images are largely reflected-UV images, but we can see some fluorescence. The predominance of green indicates fluorescence output around 345nm. The top image is a normal visible image, the middle image is a “normal” tri-colour reflected UV image, and the lower image is UV-Induced UVA Fluorscence made using the 254nm lamp. In all cases, WB was against the PTFE background. Rainbow Flourite Pink Aragonite Group 1

I have a KuangRen Macro Twin lite KX-800 that I bought for Macro photography. A couple months ago, out of curiosity, I decided to removed the two plastic front panels to see if I could modify the twin speedlite for UVIVF. The speedlite tube looks similar to Yongnuo YV560IV that I modified for UVIVF. So I placed two ZWB2 filters and surprised to discover those two small speedlites produce enough UV for UVIVF photography. I don't have any equipment to test how much UV the twin speedlite produced but still! What a nice surprise! I really like how convenient to use the Macro twin flash for my field observations. I document UVIVF on wildflowers for INaturalist. I am thinking to change the LED emitter of focus assist light to an UV 365nm LED emitter. Is there anyone you would recommend who would modify my Macro twin flashlight? Thank you! Michelle

Here is a pumpkin (or in some parts of the world, a squash) using Laser-Stimulated Fluorescence (LSF). LSF was described in my first post on it back here. Please reference that post for the procedure and background, safety requirements, and equipment used. Camera was the Sony A7S (modified). Lens was the Nikkor 20mm/3.5 (which I haven't tested in UV reflectance). Filters on camera were the Tiffen Haze 2E + BG38 2mm. 30 sec, F/16 (for depth of field reasons), ISO400. White balance altered to suit taste.

Here is some images i did of various outdoor and natures objects. Was already chilly at night so plantlife was fading. Camera used is a SonyA6000 modified + uv/ir cut filter + green filter + in camera white balance Lumanpro 365nm torch 10 seconds at night, painted with the torch

I first read about Laser-Stimulated Fluorescence (LSF, sometimes also called Laser-induced Fluorescence, LIF) in the paper, "Laser-Stimulated Fluorescence in Paleontology" (Kaye et al., 2015) which has spectacular photos of fossils produced by this method. The main advantages of LSF over UVIVF is simply that laser beams are (1) columnated, so it's possible to do fluorescence photos at a distance from the subject where a torch is impractical, and (2) extremely intense, depending on the laser, with the possibility to see faint fluorescence which would otherwise not be able to be imaged. My main motivation is actually item 1 — I would like to do fluorescence photos of large objects (especially the kind of faded signs that I used Independent Component Analysis on here). I highly recommend reading that Kaye et al. paper, which has almost all the information you need to get set up, as well as beautiful fossil photos. Kaye and another student have also written another paper on LSF in caves, which has gorgeous photos. I highly recommend both of these papers as "required reading" if you are interested in pursuing LSF. If you prefer to get your information in audio format, both authors talk for 38 minutes , which has some info that isn't mentioned in either of the papers as well as their personal experiences. Basic Setup and Methodology (from Kaye et al., 2015) We are all familiar with the light painting technique, but in this case, because lasers usually produce only a single bright spot, it isn't practical to directly implement it. Instead, the optimal setup is a laser with a special lens called a Powell lens which spreads the beam into a uniform line. If you buy a laser online, they will sell you one with a "line lens" but it will be a cylindrical lens that does not produce uniform flux. Powell lenses are much better for this application. They can be purchased many places and I haven't bought one yet -- I am using a cylindrical lens for the experiment below, however I plan to get a Powell soon. The authors recommend Powell lenses that have very small angles to keep the irradiance high and keep the beam easy to direct. ThorLabs link to Powell lenses For the choice of laser, in the papers above they usually use powers between 150mW and 500mW and 405nm. Technically it is a violet-induced fluorescence rather than UVIVF. I chose to buy a 100mW laser with a 120 degree cylindrical lens (cheap Chinese laser, $30) for my first attempt, and then once I understand the method and limitations better, I plan to buy a more powerful laser and a Powell lens of perhaps 10 or 20 degrees. WARNING: Do NOT use any laser beyond 500mW! Not only is it overkill for this application, laser power can be non-intuitive for people who haven't used lasers before: a 1W laser can burn matches, pop balloons, start wild fires. A 5W laser will cut plastic sheets nicely and put an eye out with ease. For filtering the source, no filter is needed on 405nm lasers, but if you try a green laser, you may need to filter out infrared with a BG38 or something because green lasers are really infrared lasers that go through a crystal that converts the beam to green. Many of them leak infrared, sometimes dangerously. For filtering the camera, I am currently using a Tiffen Haze 2E filter + BG38 2mm just like I use for other fluorescence photos. I am not yet sure whether the 2E has enough blocking at 405nm to stop the laser. Some experiments need to be done to verify this. The authors have built a motorized setup to do the light painting automatically. This is not necessary, but in my first test I found that it's very easy to linger too long in one location with the laser-line and make an accidental bright spot. I think building a motorized setup is a good idea to get uniform results. Safety Lasers are a completely different beast than the sources we are used to on here and need different safety precautions. 1) You NEED safety glasses. They are not optional, not even for the lower end of the power scale mentioned above. These are Class IIIB lasers, they can cause eye damage fairly quickly at close range, even when spread into a line. - When purchasing safety glasses, you must select glasses that filter the wavelength of laser you are using (405nm in this case) and with sufficient OD for the power of laser (mine are rated to OD6). - Look for glasses that are wrap-around and protect the sides and bottom from reflections. With lasers, the reflections can be almost as bad as the original beam. Even DIFFUSE laser light over sufficiently long periods can cause eye problems. 2) My friend who has worked with lasers cautioned me that the safety glasses must NOT be scratched because that significantly weakens their protection, so always keep them in their case when not in use. 3) All reflecting items (mirrors, shiny surfaces) should be covered beforehand. 4) Outdoors, lasers should not be used around other people. Obviously never shine them where they might hit a driver, a pilot, or shine in someone's eyes. As well as immoral, it's very illegal in the US (and probably in most countries). My plans with regard to imaging signage is to pick locations that are abandoned. 5) It's probably a good idea to know beforehand whether (or at what distance) the beam produces significant heating. You don't want to set your subject (or worse, dry vegetation) on fire. Goes double if you live in a dry place like the US southwest. Know before you go. In addition to the above, I found a forum for laser hobbyists that has a nice sticky on getting started with lasers, including an (even more) elaborate section on safety than I included here. First Test Here is the same gourd that I did UVIVF on previously. The exact same color profile was used here to allow for comparison. The laser was light painted from very close to keep the intensity very high. The beam spread was 120 degrees, which is inconveniently large, and no significant heating was observed at any distance. LSF, Micro-Nikkor 55mm/2.8, BG38 2mm + Tiffen Haze 2E Laser: 405nm, 100mW (nominal), cylindrical lens, distance roughly 1/3 meter. F/8, 30", ISO100 For comparison, here was the UVIVF result from before. Note that several months have passed and additional mould has grown. Final Notes My experience with the Chinese seller, Laserlands, was atrocious. They did not respond to repeated emails, nor to Skype, nor to a Facebook contact, for weeks. I will not buy any more lasers from them and would recommend keeping far away. Also, my intent, if Andrea agrees and if there's sufficient interest, would be to expand this post into a sticky.

Taken with the Noflexar 35/3.5 and Tiffen Haze 2E + BG38 2mm. Nemo torch with fluorescent ring hidden behind the front filter. Colors handled as described in my gourd post. F/16 30" ISO200 (probably should have done F/8 30" ISO100, but I just messed around with it till it looked acceptable)

When I posted this, my friend said she at first thought that yet ANOTHER common animal was showing fluorescence. I told her it was a lepus aeris. -- This was produced with the same background light subtraction method that I used with the tree stump and Queen Anne's Lace previously. See those posts for technical details. The lens was the Noflexar 35/3.5, the filters were the usual Tiffen 2E + BG38 2mm on the camera, and the Nemo's own filter. The Nemo had previously been modified by moving the white fluorescent band behind the filter. Colors here were originally done using the setup for the gourd but I subsequently increased saturation. The background has had artifacts (mainly dead pixels and line noise) removed. This bunny has previously been captured in UV reflectography back here: https://www.ultravio...__fromsearch__1

Spectralon fluorescence? Well, You be the judge. The one thing I might add is that after I shot these shots, I re-sanded the Spectralon (according to their directions) to make sure I had a clean pristine surface. The sanding cleaned it up, yes, but the surface still fluoresced the same 'gray?' surface, same intensity, no difference other than the dust and smudges were gone. Three shots of the Spectralon, (left) Visual, camera has Zeiss T* + S8612 1.75mm on the lens. (center/left) UVIVF #1, Spectralon and Straight-on torch shot, using Convoy S2+ 365nm Nichia with U-340 2mm filter on it, and the camera only has Zeiss T* on it. Both Spectralon and Torch shots have the same settings. (right)UVIFF #2, Spectralon and Straight-on torch shot, using Convoy S2+ 365nm Nichia with U-340 2mm filter on it, and the camera only has Zeiss T* + S8612 1.75mm (3.5mm) on it. Both Spectralon and Torch shots have the same settings. Settings are noted on test photos. Direct head-on shot of U-340 2mm filtered Convoy/Nichia 365nm UV torch These correspond directly to the photos below each torch shot. Dark room. Some background fluorescence reflected off the left hand black torch glass filter front. The first two shot/setting to the left correspond to the two left hand torch shots and setting above. You decide. I don't want to think Spectralon fluoresces, so show me I am wrong.

I’ve completed my first fluorescence project. The idea was to look at fluorescence patterns of various rock samples under different excitation and output bands. This images are not very exciting from the artistic point of view (esp. when compared with the other excellent fluorescence images posted on UVP), but the objective was to extract information rather than create aesthetic images. Here are the results (based on a Powerpoint I put together for a geoscientist friend who’d given me some guidance and wanted to see how I got on). Filters and lighting had been discussed in another post on UVP – the actual lighting, filters, and camera used are listed after the images. I was a bit disappointed that the spectrum of the output does not generally vary with the colour of the excitation, so you don’t seeing much difference whether the excitation is UV or visible, or whether the generated fluorescence is in the visible or IR bands. Typically I started doing desk research after I’d spent time on the experimental work, and found the following on Wikipedia: Kasha's rule ... The Kasha–Vavilov rule does not always apply and is violated severely in many simple molecules. A somewhat more reliable statement, although still with exceptions, would be that the fluorescence spectrum shows very little dependence on the wavelength of exciting radiation . So it looks like the results are in line with expectations. In some scenarios there is some filter leakage (even where the graphs indicated it wouldn’t be a problem) and background light pollution (as I didn’t have anything like a cellar to work in). So some scenarios could not be achieved where the level of fluorescence was too low: e.g. when creating the tri-colour IR images the exposure through the 1000 nm filter (red channel) was 400 x the exposure through the 750 nm filter (blue channel), which became an impossible task when combined with putting bandpass filters over the light source. For Visible induced Visible Fluorescence, I mitigated the effect of filter leakage by making two exposures: (1) the fluorescence exposure using the filters described below, and (2) a second exposure with the camera and illumination filters swapped over. The second exposure should record approximately the same leakage, but would not record any fluorescence. Then I took the difference between the two images in post-processing. Anyway, here are the results. …………………………. Lighting and Filters For UV excitation: Lightsource: Nemo UV torch, with in-built filter Filter: Baader U supplementary filter For Visible excitation: Lightsource: Lumitact G700 torch Filters for White excitation for IR fluorescence: Baader UV/IR Cut + Unbranded UV/IR Cut + Tiffen 2A Filters for Blue Excitation for IR fluorescence: Baader UV/IR Cut + Midwest Optical BP470 Filters for Green Excitation for IR fluorescence: Baader UV/IR Cut + Midwest Optical BN520 Filters for Red Excitation for IR fluorescence: Baader UV/IR Cut + Midwest Optical BP635 Filters for Blue Excitation for Visible (Red) fluorescence: Midwest Optical BP470 + S8612 + Kodak 80A Filters for Green Excitation for Visible (Red) fluorescence: Midwest Optical BN520 + S8612 + Kodak 80A Cameras and Filters: For Visible Fluorescence: Camera: Non-modified Canon EOS 6D II, Canon EF 50mm f/1.8 lens Filters when capturing all visible fluorescence (UVIVF): Baader UV/IR Cut + Tiffen 2A Filter when capturing red fluorescence from Blue or Green excitation: Baader UV/IR Cut + R25 + Midwest Optical BP635 For IR Fluorescence: Camera: Sony A6000 modified for full spectrum, Canon EF 50mm f/1.8 lens Filters for Blue channel image: R72 + Midwest Optical BP735 Filter for Green channel image: Midwest Optical BN850 Filter for Red channel image: Midwest Optical LP1000

No flies were harmed in the production of this image. Found a dead and slightly squished fly, so obviously what did I do... RIP little bugger. UV source - uv torch with ZBW2 Camera - panasonic lumix dmc-tz100 UVIVF and visible for reference

UVIVF of some lenses. I wiped them down (dry) with a microfiber before photographing them, but there was still a lot of dust. You have no idea how much dust is on your equipment until you look at the fluorescence. So much dust. The lenses were sitting on a piece of aluminum foil (which does not fluoresce). The procedure, equipment, color profile, and white balance were the same ones I used for the gourd awhile ago. Super-Takumar 50/1.4 - this is a nice lens but it has a natural yellow color (in normal light) from the radioactive thorium in the glass. Here it glows in UV. EL-Nikkor 80/5.6 metal Autocrat 75/3.5 Dinner, chana masala and rice Dinner, reflected visible light

Had some fun with this white alstroemetria I got from the supermarket. UV induced visible Panazonic lumix dmc-tz100 UV torch with ZWB2 Infrared Self converted Nikon coolpix p7700 760nm IR pass Lighting is a LED reading lamp Custom white balance on grass UV induced infrared (mi first! my god focusing was hard work but so happy with the results) Self converted Nikon coolpix p7700 760nm IR pass UV torch with ZWB2 Custom white balance on grass And visible for reference Guess now I have to try everything with IR fluorescence!