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Not sure what this is, but obviously a close relative of black-eyed Susans. This flower continued the trend where the disc flowers of aster family flowers are interesting in SWIR. Visible The colors are not quite true on this, because I did an autotone in PS, but they came out so nice that I kept it anyway. The yellow parts of the flower stayed yellow, though. UV-A This is HDR with 4 images. WB off PTFE, didn't monkey with the colors much beyond what the HDR did to it. SWIR A large panorama with 164 images.

This is a cultivar, found growing in a bush. It matches the existing UV signature for that species on the site here. (The only other thing it could be is dwarf cinquefoil, but the leaves don't match. Or, I suppose, some other cinquefoil that we don't have a record of on the site yet.) Of note, the SWIR image showed some interesting effects on the anthers(?) around the center of the flower. (I am not confident of my botanical vocabulary here.) Visible and UV-A photos were taken with the Resolve 60mm lens on my old NEX-7 camera (which is APS-C and therefore is better covered by the small image circle of the Resolve lens). SWIR was with the TriWave camera. I did not record exposure info. Visible (BG38 2mm+DB850 stack) UV (330WB80 filter) This image is an HDR made from 4 exposures, because those petals were very very dark. SWIR (Thorlabs 1500nm long pass filter, and the camera cuts off at 1600nm) This is a pano (as all my SWIR pics are now, since that's the only way to get a decent resolution). I also oversharpened it, but oh well.

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.

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

(The black is electrical tape to hold the bill flat.) Front, Visible: Front, SWIR 1500-1600nm: Rear, Visible: Rear, SWIR 1500-1600nm:

I took a photo of a coneflower several days ago, and people were curious about what would happen if I repeated the photos with the dried flower, because water strongly absorbs SWIR light, so the pattern may simply reflect the water distribution in the flower. The flower was picked on July 12, at 12am and imaged immediately after picking. Because this was not a planned experiment, I did not write down all the exact photographic settings that I used in this image set, so the followup may have slightly different contrast. I don't think it will matter for the purpose, since we are not trying to extract quantitative information. The flower was reimaged just now (July 15, 3am), 75 hours later. In order to make a valid comparison, I think I need to show how the images look straight out of camera, with no processing, in both sets. Then I will show the processed results. This is SOC, except for resizing and labeling. After subtracting off the pattern noise of the sensor, here are the results: And with sharpening and local contrast adjustment: There is clearly no significant change in "SWIR signature" of this flower after it is thoroughly dried.

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.

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

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.

This morning glory had a rather startling UV pattern (I was not expecting the star/pentagon) and a boring SWIR pattern. So far, the SWIR pattern seems quite independent of the other bands. Sometimes it looks like the NIR, sometimes it looks like the UV, and sometimes neither. Shooting details except for exposure are the same as for the other flowers in this recent series, so I'm not going to repeat the info. See the daisy fleabane post for details. Visible halogen, BG38 2mm, F16 0.2" iso50 UV Convoy S2+, S8612 1.75mm + UG11 2mm, F16 iso200 15" SWIR halogen, 1500nm-1600nm

I tried imaging a flower, which may be Greater Celandine. Excuse the iPhone photos, they are for ID purposes and to show a sample of how the flower appears in visible light. In SWIR. It appears there are no remarkable patterns to be seen here. The leaf was actually more interesting than the flower, since the strong absorption by water makes the patterns on the back stand out.

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.

The Meyer Trioplan 2.8/100 is expensive because it makes pretty bubble bokeh, but is far too expensive for me. I took the much cheaper Pentacon 2.8/150 medium-format slide projector triplet lens (a rebranding of the Meyer Diaplan 2.8/150) and mounted it to a helicoid mounted to a tilt-shift adapter on my full-spectrum modified 5Dmk2. Due to the large medium-format image circle it tolerates tilt-shift well. Brief tests showed it approx -2/3EV vs the Steinheil Cassar 2.8/50 in ultraviolet. I was getting 1/100th to 1/160th earlier in the day (at ISO3200). Pentacon 2.8/150 + 62.5mm->M65 adapter + M65 chinese heliciod + M65->Pentacon Six adapter + Tilt-shift adapter [Pentacon Six->EF] + Full-spectrum Canon 5D mark II Since the lens has an extremely similar optical design to the Trioplan, it produces the classic meyer bubble bokeh and triplet highlight glow. Of course, because it's 2.8/150 rather than 2.8/100, the bubble-bokeh is much larger. Although the photos appear to be soft, the lens actually retains detail remarkably well on close inspection, even on full-tilt. I've never heard of someone mounting a Pentacon/Meyer 2.8/150 to a tilt-shift adapter before - maybe this a noteworthy discovery. Tests with minimal adjustments: Ultraviolet [77mm BG-39 + UG-11]. Slow shutter speed here - it was evening so I didn't have much UV to work with, especially under the trees. 1/15th at ISO3200. Wild cockatoo that tolerated me after some patience. Full-spectrum. Bubbles and triplet highlight glow. Highlighting the tilt-shift a little more (full-spectrum): These were just super-quick tests. Hopefully once I get some time I'll take some proper photos to post. Yes, there is dust on my sensor. Edit: Bonus bubbles - full spectrum at night (also bonus sensor dust)

(Borrowed from the lime thread.) You are correct. The cutoff is actually closer to 1125nm. So the SWIR is photographed using a fluorescent screen that upconverts SWIR photons into NIR photons. Physically, it is the anti-Stokes effect. The converter tube and screen are the CamIR Adapter, which is the same as the Edmund Optics version, which I obtained on eBay. I paid about 12% of Edmund's price! (I believe this to be the cheapest SWIR camera setup in existence! ...and it was still too damn expensive. :( ) This is with the Cine Velostigmat 25mm/F1.5 (20", F/1.5, ISO1600) With a Thorlabs 50mm SM1-mount lens (F/2)

The following two spectra suggested an experiment. Edmund Scientific's sodium chloride spectrum M. Blanco and M. A. Romero. Near-infrared libraries in the pharmaceutical industry: a solution for identity confirmation. Analyst, 126:2212–2217, 2001. And, indeed, they seem to behave as advertised! Salt on the left, sugar on the right, of course. Visible, 1064BP30 (with Noflexar lens), and 1480-1600nm phosphor + Thorlabs BBAR-coated SWIR lens

Ultraviolet, visible, infrared, short wave infrared comparison UV taken with a full spectrum Sony A7, and the filter stack consists of Schott UG11 - 2mm, Schott 8612 - 2mm, and interference film coating that blocks from 600-900nm Vis taken with a standard Sony A7 IR taken with a full spectrum Sony A7 and a Hoya R72 SWIR taken with http://www.infraredl...ve_Camera.shtml and a 1500nm long pass filter The dark skin in the SWIR shot is because the water absorption at 1450nm http://upload.wikime..._absorption.png