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I tried a St. John's Wort. The UV was mostly for comparison to the SWIR, but it came out rather nicely. What a lovely flower this is in UV! Visible sunshine, Resolve 60mm quartz lens, F16, iso2500, 0.02", DB850 + S8612 1.75mm UV sunshine, Resolve 60mm quartz lens, F16, iso2500, 2", 330WB80 filter SWIR 1500-1600nm pano shot with 50mm Thorlabs SWIR-coated achromatic doublet, stopped down. The filter was a Thorlabs 1500nm long pass. Camera was the TriWave, and currently I have no idea how to quantify the exposure settings.

This is either a chrysanthemum or dahlia, I think, and I forgot to get pics of the leaves again, so it will have to wait a while. Anyway, it's a pretty yellow flower. Visible (Resolve 60mm lens, forgot to note exposure, converted Sony A7S camera, and an S8612 1.75mm+DB850 dual band filter for visible) UV (Resolve 60mm lens, F/16, 20", ISO1000, converted Sony A7S camera, and 330WB80 filter) UVIVF (Noflexar 35mm/3.5, F/11 30" ISO3200, converted Sony A7S camera, and an S8612 1.75mm+DB850 dual band filter for visible) With Convoy S2+ torch. SWIR 1500-1600nm (Wollensak 25mm lens, no idea how to note exposure, TriWave Ge-CMOS camera, and Thorlabs 1500nm long pass filter) This is a pano with the size reduced to increase quality.

Visible (sunshine, Resolve 60mm quartz lens, S8612 1.75mm + DB850 filter, Sony A7S camera, F16 ISO200 1/60") UV-A (sunshine, Resolve 60mm quartz lens, 330WB80 filter, Sony A7S camera, F16 ISO3200 2") UV video of tiny insects or arachnids coming out of center of flower when UV light is shined on it. They would not come out for visible light. Click through to make it big to see them better. They are very very tiny. https://youtube.com/52LwcRVlzF8 Visible (halogen, Resolve 60mm quartz lens, S8612 1.75mm + DB850 filter, Sony A7S camera, F8 ISO80 0.4") UVIVF (Convoy S2+ torch, Resolve 60mm quartz lens, S8612 1.75mm + DB850 filter, Sony A7S camera, F8 ISO1600 15") SWIR (halogen, Wollensak 25mm lens, Thorlabs 1500nm LP filter, Triwave camera, and god only knows how to quantify the exposure for this.) This is a pano. In situ photo for ID help.

This was intended to be a test of the TriWave for UV mainly. Chinese trumpetvine UV with 330WB80 and Resolve 60mm lens (quartz) in sunshine on Sony A7S Vis (iPhone shot) UV with 330WB80 and Resolve 60mm lens (quartz) on Triwave with Convoy torch. It does UV just fine, although I noticed a tendency to have problems with the dynamic range. This is an HDR image to overcome the dynamic range issues. The smaller field of view is due to the 1/2" TriWave sensor mostly. Vis with BG38 2mm + DB850 dual band filters and Resolve 60mm lens on Sony A7S under halogen SWIR on TriWave with Wollensak 25mm lens and Thorlabs 1500nm LP filter. Pano of a few images to get slightly better resolution.

Some time ago, I started wondering about whether it was practical to have a set of "standard", cheap and easily obtainable materials that reflect in the commonly seen UV false colors. This set of materials would be very useful as an easier-to-use alternative to bandpass filter strips like the "Sparticle" (these filters are expensive and made in small series, so future availability is questionable) and to specific flowers (available only in particular regions and seasons). This is only a starting attempts, and I am the first to object to my initial choice of test materials: plastics are very often mixed with additives, UV blockers, plasticizers and a host of other chemicals, usually undocumented. Many of the common "plastics" have specific names, but can actually be a mixture of different chemical species, once more, usually undocumented. Nylon is an example. Nonetheless, I/we have to start somewhere. In this test I left out PTFE, since we already know it is a good reflector of UV with a relatively flat spectral distribution, so not useful as a false-color target. Here is a set of five plastic sheets in VIS, all except the bottom one chosen because they are white/whitish and, according to the seller, natural (i.e. not colored): From top to bottom: "Nylon" Unplasticized polyvinyl chloride (uPVC) Polypropylene (PP) High-density polyethylene (HDPE) Light-grey colored plastic box, most likely polypropylene (PVC) with added colorants, plasticizers and possibly UV absorbers and the same in UV with Sony A7 II, Coastalopt 60 mm Apo, Baader U, Bowens 1500 Pro studio flash with non-coated Bowens tube, custom WB set with this equipment in sunlight. They all are fairly "white" in UVA, with the exception of uPVC and the (likely) PVC box, which have the same blue false color. Not much to show as a result, except that PVC and its uPVC variant seem to be a reasonable candidate for a false-blue target (the exact blue or violetish-blue shade depends in large part also on the CWB used). This could be a start.

I believe this flower is yellow [dotted] loosestrife. Title will be amended if I'm wrong. :) Camera (except for SWIR) was Sony A7S converted, lens was EL-Nikkor 80mm/5.6. For SWIR, the Wollensack 25mm/1.4 lens was used. Visible 650-405nm using BG38 2mm and DB850 dual bandpass filter UV This is under Convoy S2+ 365nm. Filters were S8612 1.75mm and UG11 2mm. Saturation drastically boosted. This is in sunshine. IRG With Tiffen #12 and DB850 dual bandpass filters. UVIVF BG38 2mm and DB850 dual bandpass filters on the camera, and a filtered Convoy S2+. White balance chosen to roughly match the flower color as it looked to me. UVIIF Hoya R72 on the camera, filtered Convoy S2+ SWIR 1500-1600 TriWave camera, 1500-1600nm Thorlabs bandpass filter

I've just had a paper published on measuring spectral response of cameras (from 280nm to 800nm), using the technique I developed and have discussed on here. I compared a monochrome and multispectral conversion. Here's the link to the article; https://www.tandfonline.com/doi/full/10.1080/13682199.2019.1638664 If anyone would like a copy and doesn't have access to it, drop me a message.

Hello. I’m curious if anybody could recommend cheap but sensitive, low risk modification camera’s to use for UV/IR photography? After attempting modify modern camera I came to realize they are too complex, brittle and expensive devices to us for modification. Sony has very sensitive IMX322 0.0001Lux and yet inexpensive camera but unfortunately it only supports AHD DVR devices. Some CCTV camera’s are even made monochrome so they are even more sensitive especially to deeper UV. USB camera’s aren’t so sensitive but it’s possible to find more sensitive and backlit CMOS camera’s. They can be even hooked to phones but unfortunately only having android system. Their lens are also easier to customize and I even seen sold M12 UV grade fused silica lens. Smaller sensors also mean cheaper filters. I also consider modifying modern smartphone to full spectrum. My Lumia 640 has amazing sensitivity to low light conditions rivaling even Sony A3000. So I imagine it could make good UV/IR camera that will be also compact and easily portable. Not sure if it would easy to convert phone to full spectrum. Anybody tried using phones or such camera’s for this purpose?

Some kind of coneflower. Same setup as the Daisy fleabane, etc. with similar exposure times and processing. Visible: UVIVF: UV: 1000nm long pass (Chinese filter alert, but I've roughly confirmed it using known bandpass filters stacked with it): SWIR (1500-1600nm band pass): (I had do to HDR on this in order to get both the dark center and the ray petals. The rays are really light, and the center is really dark, much more contrasty than shown.) Center closeup without HDR: Remarks: Another example where the SWIR result does not really match any of the others. I am going to let this flower dry out and we will see what happens to the colors. Hopefully it's sturdy enough that it won't be unrecognizable. This flower followed the same pattern as the daisy fleabane (dark center, light ray petals) and they are obviously related to each other. That UV is really REALLY dark. That flower would be invisible except for the specular reflections. The 1000-1100nm IR looks nothing like the 1500-1600nm IR. I really want to get some more band pass filters and track the changes as you go more gradually to longer wavelength.

I found that a buttercup (exact species of Ranunculus to be determined) shows patterns in SWIR that match the ultraviolet pattern. First the visible image, taken with the Sony A7S using BG38 2mm under an "energy saving" halogen light. WB was off PTFE. F16 0.8" ISO50 Next the UV image, same camera, using S8612 1.75mm + UG11 2mm and a Convy S2+ torch. WB again off PTFE. F16 6" ISO1000 Then the standard, featureless NIR rendition using a nameless Chinese IR1000 filter (obviously the exact cutoff is unknown since it's a no-name). Halogen again. F16 2.5" ISO80 Finally the SWIR results using the TriWave Ge-CMOS camera under halogen. 1500-1600nm Thorlabs bandpass filter

This seems to be an evening primrose (of which there are a number of species) or something like that. It was photographed around midnight, so I suppose it is living up to the name. Cameras: Sony A7S for visible, UV, and UVIVF, TriWave Ge-CMOS for SWIR (1500-1600nm) Lighting: halogen for visible and SWIR, filtered Convoy S2+ for UV and UVIVF Filters: for UV, S8612 1.75mm + UG11 2mm (although none was really needed since the torch is filtered also, but it's my standard stack) for visible and UVIVF: BG38 2mm + Hoya UVIR cut for SWIR: 1500nm long pass from Thorlabs (FEL1500) Visible UV UVIVF [note: do not give me any grief about the damn white balance. My EYES don't even see the same colors as the rest of the board, how do you expect me to get it right? I made it look pretty.] SWIR (1500-1600nm) The SWIR patterning is quite interesting as it has aspects of the UV pattern here too, but is not identical, as the SWIR shows a dark bulls-eye at the center which is not there in UV. Also the anthers are very reflective in the SWIR photo. We should probably keep in mind that this is just the 1500-1600nm SWIR band -- I have not investigated other sub-bands of SWIR yet:

The visible and UV are both F/16, ISO100 and 0.8" and 5" respectively. Filters were BG38 2mm + Hoya UVIR cut for visible, and S8612 1.75mm + UG11 2mm for UV. Camera was the Sony A7S. SWIR (1500-1600nm) is F/4-ish but focal stacked, 2/15", gain=0.5 using the Wollansak 25mm lens (which apparently works nicely from UV to SWIR) and the 1500nm long pass filter from Thorlabs. Camera was the NoblePeak TriWave. Visible UV SWIR (1500-1600nm) This is a focal stack of 12 images.

This flower, which I'm initially categorizing as a daisy fleabane, showed unique patterns in all four bands that were tested. The visible, UV, and NIR responses are well-known, but I'm not sure the SWIR response (1500-1600nm) has been visualized before. As can be seen below, the ray petals seem to be light gray, and the disk is very dark, with white flecks. My intent is to get a filter wheel soon and make "true color" SWIR photos using three sub-bands. This flower is high on my list of ones I would like to see in color SWIR! halogen, Sony A7S, Noflexar 35mm/3.5, BG38 2mm, F16 1.6" iso80 contrast adjusted ConvoyS2+, Sony A7S, Noflexar 35mm/3.5, S8612 1.75mm + UG11 2mm, F16 iso1000 15" saturation boosted, contrast adjusted halogen, Sony A7S, Noflexar 35mm/3.5, generic 1000nm longpass, F16 iso100 2" contrast adjusted halogen, TriWave Ge-CMOS, Kowa LM12HC-SW 12.5mm/1.4, 1500-1600nm Thorlabs filter, F1.4 gain=0.5 0.033" focal stacked, denoised, contrast adjusted, sharpened

Thinking about absorption of and the fuzzy limit of looking through stuff. I am becoming interested in what allows for the reflection of light we see. So I set up a first attempt test with stuff to try and represent "pure" forms of salt, fat, protein, plastic and other. However, I know what I have here is not ideal. Also couldn't think of a best pure protein source. Maybe a chunk of Marmite may work (yeast extract), I actually have a jar. I have a 15W long tube 302nm bulb above the stuff and one immediately in front, shinning slightly upwards. These are about as close as I can get to the stuff. They also allow for a nice range of UV and into IR, that nearly matches the cameras response as Johnathan has shown. The lens is Pentax UAT at F8 for all images on my full spectrum EM1 Visible labeled image: 1000nm 2mm filter ISO 400, 4 seconds: 720nm fitler ISO 200, 1.3 seconds: No filter (unlabeled), ISO 200, 1/20 seconds: 330WB80 improved filter, UVA at ISO 200, 2 seconds: 313bp25 with 330WB80 (to cut any IR), ISO 200, 15 seconds: 300bp10 with 330WB80 (to cut any IR), ISO 800, 30 seconds: 280bp10 with 330WB80 (to cut any IR), Auto color adjust in IrfanViewer, ISO 800, 60 seconds: 280bp10 with 330WB80 (to cut any IR), Auto color adjust in IrfanViewer, ISO 800, 1118.4 seconds: Not surprisingly PTFE is the best at reflecting the light through all wavelengths. Plastic wrap was also good, as was plastic metal looking like foil. The Coca butter (pure fat) also was reflective down at 280nm, as was the salt and rock. The other stuff is hard to see. But I don't think the sugar is very reflective in UV and may be what causes the darkness we see in flowers. I will have to test with a white sugar cube one day.

The two purposes of this mini-project were to see if the usual trend of patinas on old books becoming more transparent as one goes deeper into the near infrared continues into the shortwave region, and secondly, to see how far it is possible to push the TriWave camera output quality, and whether one can obtain high quality photos with it at all, given the resolution limitation of analog NTSC video. The book in question is "Adventures of a French Soldier: Exemplifying the Evil, Crime and Sufferings of War, with Reflections" (1831). Summary First the main results. The SWIR photo (1500-1600nm) does seem more legible than the NIR photos. I did not keep as close an eye on exposure times as I wish I had, so there will be some variation due to unequal exposure, but I did my best to correct for that in post processing. It is very hard in any case given that the images were taken with different cameras and different types of camera even. In addition, the SWIR image is a panorama. By a procedure described below, it is possible to greatly improve the output of the SWIR camera though a "white frame subtraction." This was done on the SWIR images prior to building the panorama. The final output quality was only slightly inferior to the Sony A7S. The large versions now follow, along with shooting details. UV (Sony A7S, S8612 1.75mm + UG11 2mm, with a Convoy S2+ torch. F/16 ISO3200 10") Visible (Sony A7S, BG38 2mm, halogen bulb, F/16 ISO320 0.25") NIR 720nm long pass (Sony A7S, Hoya R72, halogen bulb, F/16 ISO250 0.25") NIR 1000nm long pass (Sony A7S, unknown 1000nm eBay filter, halogen bulb, F/16 ISO2500 0.25") SWIR 1500nm long pass (TriWave, Thorlabs FEL1500, halogen bulb, F/4, analog gain=1, 15fps, 405 lines of integration per frame, no gamma curve, digital gain=1, digital offset = 0, with dark frame subtraction on) This is a panorama of 46 images stitched in Photoshop, then sharpened in Smart Deblur. ---------------------- Process for Construction of the SWIR Panorama Next, I will discuss the process flow for the construction of the SWIR panorama. To begin with, a typical image from the camera looked like this (unprocessed in any way, original size): Looking carefully, one can see there are a lot of artifacts, some from the sensor, some from a dichroic reflection (which I plan to take care of by finding a different filter attachment method eventually, and maybe a lens hood). My next step was to remove the dichroic reflection and the sensor glitches by taking a "white frame" and combining it with each image from the panorama in MATLAB. The white frame looked like this: By fiddling in Photoshop, I discovered that inverting the white frame, doing a 50% opacity "Darker Color" blend in Layers, flattening the image, and adjusting the contrast would eliminate the ring. I then replicated this procedure in a MATLAB script and did it for every image in a batch. (I could probably have made a PS action to do this, but I chose not to, because I would rather keep my workflow in MATLAB as much as possible.) After this procedure, the image looks like this: At this point all the images were combined into a panorama in Photoshop, and then it was sharpened in Smart Deblur. --- Conclusions My conclusion is that the output image quality is acceptable, especially when tiled into a panorama with the white frame subtraction method. Here is a second, more dramatic example of the difference the white frame method makes, but on a different photographic subject: This made such a difference to the final results that it will be used in all further work with this camera.

I spent some time by the pond near my apartment. I've taken photos there previously which you can see on the board here and also captured St. John's Seminary (visible across the water) in LWIR here. Some of the locations are the same, but the wavelengths involved are different in this post. First a UV shot. I found an interesting way to alter the false colors here, by doing a channel swap and then rotating the hue in the Photoshop hue-saturation dialog until the sky became blue. A side effect was that the seminary looks like a golden castle. Here is a crop of the seminary: Here are some irises (iris versicolor, probably) growing by the water's edge. The colors are the board's standard UV (post WB) colors. Night fell. Those irises fluoresced nicely. And here's the seminary in LWIR. I really need to get a LWIR lens with a smaller field of view.

I think this is a false orange blossom, although I'm open to correction. [Note: changed to Mock-orange in title.] A sample of the leaves is below for ID purposes. But let's start with the good photos. Of note, the SWIR photos looked identical to the NIR ones for this flower, unlike for the buttercup. Visible halogen, Sony A7S, Noflexar 35mm/3.5, BG38 2mm F16 0.6" iso80 UV ConvoyS2+, Sony A7S, Noflexar 35mm/3.5, S8612 1.75mm+UG11, 2mm F16 iso1250 15" saturation increased a lot Near infrared (~1000nm) halogen, Sony A7S, Noflexar 35mm/3.5, IR 1000nm long pass, F16 2.5" iso100 focal stacked, contrast adjusted SWIR halogen, TriWave Ge-CMOS, Kowa LM12HC-SW 12.5mm/1.4 F, F1.4 gain=0.5 0.13" focal stacked, contrast adjusted, denoised and sharpened Pics for ID purposes:

Late at night the Monday before last I was idly surfing eBay, checking for SWIR cameras as I often do, when what to my wondering eye should appear, but a NoblePeak TriWave camera in "new/opened box" condition. It was Buy Now only, but for a price I considered reasonable for the camera. (As it happened, the seller had slightly misrepresented the contents in several ways, out of ignorance I think, but I am still glad I bought it. It is highly unlikely that another TriWave will come on the market any time soon.) To give a rundown on this very strange camera: It's a TEC-cooled germanium-CMOS hybrid sensor, which means it is sensitive between 300nm and 1600nm according to the company's QE graph: The company, NoblePeak, is defunct, for reasons unknown: they had been doing fairly well at raising funds apparently, and they had a technology that was winning awards, and then suddenly they vanished around 2010ish and their assets were sold off. Despite keeping an eye out, I have not seen any of their cameras on eBay until last Monday. A TriWave camera has appeared in the forum once before, in the photo by Nick Spiker here: https://www.ultravio...v-vis-nir-swir/ My version of the camera seems to be nothing like as nice as Spiker's. In fact it must be a fairly early prototype, since it is completely analog and outputs only NTSC video. For all that, I'm committed to work within its limitations and I will buy it a nice frame grabber card so I can get high quality (albeit low resolution) output from it. Today I wired it up and got it working on my Mac using the original software in Windows XP emulation (using Parallels), with a USB-RS232 cable and a cheap NTSC-to-USB capture stick (from Elgato). I had a few heart-stopping moments where no video was coming out, but it turned out to be due to the need to cool the sensor down to a chilly -80°C. I used a 1500-1600nm filter (blocked from UV to 1500nm) from Thorlabs, and a 50mm SWIR-AR-coated lens, also from Thorlabs. Here is the current setup: Here is a first image (left) of a Victorian card. I'm quite excited to play with this camera in a variety of wavelengths, including maybe trying UVB or the "true color" UV we were discussing in the other thread, since this is a monochrome camera.

I purchased four Russian filters a Y1,4x, a Y2,0x a O2,8x and a green. I can't remember the code of the green. My feeling from them is that they seem to be a multiple from a Wratten #6. Thus the Y1.4x is equivalent to a #8. The Y2x would be equivalent to a #12 and the Orange filter would be equivalent to a #16. I think the green filter is equivalent to a #11. Is this assumption correct? Has anyone collected a spectrum from the Russian filters? Do any of the Russian members know? Thank you.

Finally, a successful UV art portrait lens! I attached a ~1930's Emil Busch Neokino 120mm f2.1 petzval-design cinema projection lens to a M65 helicoid with a 62.5mm to M65 RafCamera adapter, and mounted it to a full-spectrum 5Dmk2. I drilled a hole into a Pentacon Six lens backcap that happened to snap onto the front of the lens, and superglued a 62-to-77mm step-up ring (maybe 58mm? forgot), creating a filter holder. I stacked a 77mm UG-11 and S8612 for ultraviolet. As highlighted in previous posts, this lens has phenomenal UV performance, despite being a fast telephoto. The petzval design gives beautiful bokeh and glowing highlights, although the dated optics don't give the sharpest image in town. Since the goal was art, not technical perfection, I wasn't too bothered by this. Model: James Gray. You might notice in some of the waterside photos he has a strange dark ring over his left eye. I puzzled over this for a while before figuring it out. I was wearing sunblock on the day, but he wasn't. When he looked through my LCD magnifier to see some of the images, he inadvertently acquired the sunblock that had rubbed off my face onto the eyepiece. Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Ultraviolet, Neokino 120mm f2.1 with UG-11 + S8612 Visible, Mitakon 85mm f1.2 Infrared + visible, medium-format Pentacon Six Biometar 80mm f2.8 with tilt-shift adapter Infrared (720nm), 140mm f1.8 soviet projection lens Visible, 50mm f1.2 soviet projection lens Infrared (850nm), 140mm f1.8 soviet projection lens Visible, Helios 40 (85mm f1.5) Infrared + visible, 140mm f1.8 soviet projection lens Infrared + visible, Mitakon 85mm f1.2 Visible, 50mm f1.2 soviet projection lens Infrared (850nm), 140mm f1.8 soviet projection lens Infrared + visible, Arsat 30mm medium-format fisheye lens on tilt-shift adapter

At the St.Vitus church in the neighbour village Südlohn I have had noticed some X-structures in the masonry. Now I took some NIR and Vis images. The harder burned and thus darker stones were used as half stones or header. At the ground the pattern is not fully random. Maybe, after a few meters they noticed the pattern. The structures are also visible in the visual spectral range, but are more clear in the NIR. Gear: NIR: Sony A 6000, Noflexar 35/3.5, Green.L 950 nm Filter (The combination has no hot spot up to F16) Vis: Nikon Coolpix S3200 pocket camera. Nov.15.2018 Suedlohn2058, F3.5, 1/30 sec., ISO 3200 Suedlohn4106, F3.5, 1/50 sec., ISO 80 Suedlohn2060 F3.5, 1/60 sec., ISO 2500 Suedlohn4107, F3.5, 1/50 sec., ISO 80 Nov.11.2018, Suedlohn1960, F3.5, 1/60 sec., ISO 2000

A couple of weeks ago I found a guy on eBay selling a monochrome conversion of an EOS 5D for not much money (mainly because it had a line of dead pixels in it), and I reached out to him and asked him about the conversion. He'd done it himself and mentioned he had done a few, and was now just trying to recoup some of the money he had spent on sensors and cameras. I got to wondering whether he could do me a custom modification - half and half, remove the Bayer filter/microlenses from half the sensor and leave the other half intact. Well, unsurprisingly he had never done one before but was willing to have a go on an EOS 450d he had. A few days later he lets me know it's done, and send me a sample image, and we agree a price. Then this morning it arrives.... I took it out in the garden and got a few test shots, some plants, a sunflower and a PTFE tile. These are RAW composite images from RawDigger, screenshotted and saved as jpegs. Eos 450d half and half, Asahi UAT 85mm lens, f8, ISO800, Baader U filter and lens hood. Hedge, 1s Hedge, 1/4s Sunflower, 1/3s Sunflower, 1/13s PTFE tile, 1/80s It's certainly a little rough around the edges, and with a few scratches, and the focussing is slightly off - there is no WG280 or spectrosil over the sensor, which I presume has an impact on the final focussing of the image. I must learn to use live view focussing again. The aim here was to look at the effect though, and not to use it as a fine art camera. The PTFE tile shows the increased light hitting the sensor in the monochrome side quite well. I took the RAW image of the PTFE tile and put that in Rawdigger, and measured the RGB values in 2 regions; monochrome, Bayer filter + microlenses, and then in between where the microlense have been removed but the Bayer filter remained. Plotting them out I got this; The average response for the monochrome side is about 4.5x that of the multispectral side in this case. Interestingly the area between the 2 sides, is where the top microlens layer has been removed and the Bayer filter remains. The sensitivity in that region for the Bayer filter alone, is about half of that of the Bayer filter and microlenses, so it looks like even in the UV the microlenses are doing their job and are not absorbing the UV. The Bayer filter is very highly absorbing in the UV, even more so than we thought before. So, camera manufacturers please make us a monochrome sensor with microlenses on for our UV work :) Oh, and a final picture, the sensor itself.....

Hi I'm a hobby photographer that are planing on venturing into UV / IR photographing my plan is to convert my Nikon D800 to an UV+IR only camera (as I mostly take handheld photos) by removing the AA, ICF and CFA and install a "DB395/870" / "Hoya U-330" / "SCHOTT UG11" filter on the sensor (to block visible light) and then use either at UV or IR block filter in front of the lense to either take UV or IR photos, like the "Hoya HA30" or "Hoya Y50" the main issue is trying to use 2 filters, that I will just end up blocking to much light to be able to use it handheld where dedicating til to only UV or IR would probably be the better option as then I only need one filter "X-Nite 330" for UV or "X-Nite 830" for IR also do any of you know if there exist any alternative to MaxMax in EU, so I can avoid all the problems with import/export tax Mark Petersen

On the 6th of October we took some pictures from a solar plant. The images are size reduced and enhanced. Unfortunately I have a bright spot in the middle of the NIR pictures. I found, that the SELP1650 is poor for NIR. Unexpected and very interesting are the patterns in the UV image. However, the patterns do not correlate with the defects. In the NIR and full-spectrum images, the patterns are not visible. Full-Spectrum Sony A 6000, Lens SELP1650 IR Filter: Green.L, IR950, UV Filter: Makario SP2 UV-400N Thermal image: Flir Vue 336 Full_Spectrum_DSC01570: 1/800s, f/6.3, ISO-100 NIR_DSC01520, 1/80s, f/6.3, ISO-1000 NIR_DSC01571, 1/60s, f/6.3, ISO-640, UV_DSC01543, 1/3s, f/6.3, ISO-3200 Best regards, Wilhelm

During last June's open-door helicopter flight (written up here), I had the opportunity to fly over a field that I'd walked across the previous week. From the air, I took aerochrome-style red/green/infrared shots using Tiffen #12 filter and the NEX-7 camera, as documented at the link. Quoting the relevant parts from that writeup, the processing steps were: Following that, I used Independent Component Analysis (written up here using faded ads on brick walls as an example) to bring out the hidden patterns in the fields. I visualize the three ICA components by putting them in the channels of an Lab colorspace image and adjusting contrast to align the peaks of the histograms of the a and b channels. The history of the fields is itself fascinating; they were once the Great Cedar Swamp until Cumberland Farms filled in the land in the 1970s. You can read the whole sad story at this link, but I will excerpt some pieces so you can interpret the photos below appropriately. --- #1a: #1b: #2a: #2b: #3a: #3b: In the following two photos, the original flow of the river through the swamp shows up dramatically. #4a: #4b: #5a: #5b: In this pic and the ICA below it, there is a rectangular patch that must have been cleared at some point by one of the companies involved. #6a: #6b: #7a: #7b: --------- Finally, I'll end with some visible light photos of what it looks like on the ground. I walked along the white mud path (which was littered with living snails!) that runs through the center of the former swamp. It was beautiful and filled with birds and wildflowers. The Audubon Society is trying to raise money to buy the land and save it from developers. This is the path shown in photos 4(a, b ) and 6(a, b ):