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I've been experimenting on aerochrome emulation for the last 8-9 months using a lot of information from all over the web (a lot of which I found on here). The main thing that I have found is that in order to get very distinct variations in foliage, the amount of incoming infrared light needs to be cut. It seems as though pretty much every species of tree and plant reflects the same amount of infrared (which makes sense as chlorophyll a is highly conserved between all land plant species). To this end, the triple bandpass 550/660/850 from MidOpt is attached to the rear of my lens and the HOYA X1 to the front. This leaves me with images that are extremely green, but have the correct amount of red and IR light for a successful conversion. My workflow then generally involves desaturating the greens in lightroom and then performing the standard channel swap in Photoshop. Even with somewhere between -60 and -80 saturation applied to the greens in lightroom there's is still plenty of colour left to give the deep blue sky with white fluffy clouds that I'm after so much, without having to worry about the magenta cast that I've seen mentioned before. I'll keep iterating through, and I have seen Fandy's post about using a linear colour space so I may try that out on some existing files. I also need to try out a circular polariser to see if I can get the sharp drop off in the skies that I've also seen from some film photos.

ORIGINAL DATE: 2021 August 29 UPDATE 1 Aug 2023. Removed UVR Optics NIR-Block because not strong enough at OD2 in some regions. Replaced with reccie for BG39. UPDATE: 22 May 2023. Added suggestion for finding Schott/Hoya UV dual bandpass glass now that UVIR*Optics has gone out of business. UPDATE: 22 May 2023. Added AndreaU MK II and UVBplus to Name Brand Filter list.\ UPDATE: 9 April 2024: Added warning about Tangsinuo not providing the filter thickness requested by the customer. This is a "Best" list for some basic gear. Be sure to see the 2nd post for the UV-pass filters. UVP and its Owner/Admins have no monetary affiliation with any vendor. UVP and its Owner/Admins are "gear neutral". Use what you love using! All links are for your information only and do not constitute a vendor recommendation. Search around for the best prices. The recommendations here are for basic beginner gear. Your needs might be more specific or more advanced. If so, please consult the Stickies and check recent forum discussions. Note that there are NO camera or lens recommendations!! Everybody including their 3rd cousin's brother-in-law's mother's best friend has an opinion about UV-capable lenses and cameras and those opinions are all different. Try this search tag to find recent forum discussions: Camera Search Tag. In reflected UV photography, just as in Visible photography, we can say that better sensors do give better files. However, artistry in UV photography can be accomplished with any UV gear. SHOPPING WARNING: If you find some name-brand gear online at a price which seems too good to be true, then it is probably some imitation being passed off as authentic. Please shop only at a reputable online store. As one example, Alibaba was recently selling fake Zeiss T* UV-blocking filters. SAFETY Best UV Protection Glasses or Goggles: Yes, UV light is dangerous! Ever gotten a sunburn? Ever had snow-blindness? And UV damage to eyes & skin is cumulative. Look for at least 99% blockage and wrap-around protection in the safety glasses you choose. Here are two options. McMaster-Carr 99.9% UV Protection Rating The linked page shows wraparounds, panoramics which fit around the temple, and ventilated goggles. Prices range from $9 to $30. Here is a specific link for yellow or orange tinted goggles: https://www.mcmaster.com/eye-protectors/lens-color~yellow/lens-color~orange/uv-protection-rating~99-0-/ Here is a specific link for ventilated goggles: https://www.mcmaster.com/eye-protectors/lens-color~yellow/lens-color~orange/uv-protection-rating~99-0-/lens-style~panoramic/lens-properties~ventilated/ UVEX also makes very good protective glasses/goggles. The link is to the manufacturer's website which has scads of info about sports & safety glasses. To buy UVEX goggles it's probably best to google around for the best deal on Amazon or other websites. LIGHTING Best UV Illumination: SUNLIGHT !! "-) There's more UV in Sunlight at high altitudes. There's more UV in Sunlight in the middle of the day. There's more UV in Sunlight in summer. So, mountain top at high noon in July and you're good to go! However, if Sunlight is missing at sea level in the early morning in December, then see the next entry. Next Best UV Illumination: UV-Flash The Xenon flash tube must be uncoated. The Canon 199A is a current UVP favorite for modding into a UV-flash. But there are other possibilities. Use the next link. Lighting TAG Search Click that lighting tag search for further info about UV lighting. There will be info about UV-flashes in there somewhere. Ordinary Xenon flashes can be modified (DIY) with filters to pass only UV light. **WARNING** Please remember that flash units have murderous capacitors, so do not fry yourself dead by wonking around in the wrong part of the flash unit while changing the filtration. Mod a flash unit at your own risk!! Best Basic 365-nm UV-Led Torch: Convoy S2+ UV with Nichia Chip A NOTE: Recently the no-name "Nemo" torch has been more popular with the UVP Membership. Nemo search on UVP. Nemo search on Google. A UV-Led torch is used to supply light for focus illumination on the subject while focusing through Live View, or inducing Visible or IR fluorescence in a dark room, or light-painting a reflected UV subject during a long exposure. In the past Nichia was considered the best 365nm UV-Led Chip maker. But I don't think you should worry too much about either the brand or the grade of UV-Led chip because we are looking mostly for enough output (wattage). You might need two torches depending on how you make use of them. If you can find info about the UV-Led torch chip you are considering buying, look for an A grade UV-Led for best results. TORCH NOTE 1: The Convoy S2+ Nichia A torches are well-made, well regarded and meet stated specifications. If you want something less expensive, then you can take your chances with the unbranded UV torches sold on Ebay. Many of these do not meet their stated specifications. Please check the recent forum discussions for advice on unbranded torches! TORCH NOTE 2: That third use of a UV torch there in the bullet list? Let me point out the following: it's not easy to make a reflected UV photograph using only a UV torch. Exposures are long and results are noisy. The best reflected UV photos are made in strong sunlight or using a Xenon flash with a UV-pass filter. Sunlight and UV-flash produce more false color due to the wider range of UV. Best UV Light for Beginners, Intermediates and Advanced: UVA and UVB ONLY!! As for UVC, we say NO, just NO. UVC is too dangerous. And it is very difficult to find the filters, lenses and cameras which can record below 300 nm. There's scarcely any UVC light in sunlight anyway. So where would you find illumination? You don't want to even go near those 254 nm sanitizing bulbs which will break your DNA. Frankly, IMHO, what I've seen so far in UVC photography is not particularly impressive anyway. UVC is not where the beauty of reflected UV photography lies. It just isn't. If you must play with UVC, please remember that you have been warned by UltravioletPhotography.com NOT to do this. UltravioletPhotography.com cannot and will not accept any liability for damages you may incur from UVC light. Best Filter for Basic 365-nm UV-Led Torch: Hoya U-340 x 2.0 mm LINK to Transmission Chart LEDs have a fairly narrow output, but using this filter on your torch will ensure there is no violet/blue visible contamination when the torch is being used for inducing visible fluorescence. You do not need to filter your torch for non-fluorescent work. FILTERS Best UV/IR-Blocker for making Visible Light photos with Full-Spectrum Camera There will be opportunities to use your full-spectrum conversion in visible light. So replacing the removed internal UV/IR blocking will be necessary. Kolari Hot Mirror Pro 2 Best, IMHO. Link to UV/IR-Blocker tests Kolari's newest UV/IR-Blocker has a transmission curve which matches the transmission curves of most cameras internal filtration. White balance in-camera should give you good color. Any small deviations are easily tweaked in an app or by using a color correction profile. OR Schott BG38 x 2.0mm OR B+W 038 + [Longpass UV-Blocker] Filter stacks like this are somewhat more prone to flare & ghosting in backlit scenarios. Your choices for the longpass UV-Blocking component are: Schott GG400 or Schott GG420 Most camera makers' internal UV-cut filtration begins somewhere between 400-420 nm. Filter stacks work better if one of the components has AR-coating. That costs more though. Zeiss T* UV Filter This filter is regarded by many as the best UV blocker. It is AR-coated and cuts UV very well starting between 400-410 nm. Best IR-Blocker for making Reflected-UV photos with Full-Spectrum Camera Stack one of these over your UV-pass filter for extra protection against IR contamination. Schott S8612 x 2.0 mm LINK to IR-Blocker Transmission Charts for 2.0 mm Depending on the thickness of your dual bandpass filter, you might find that a thinner S8612 will suffice. But a 2.0 is almost universally useful and is the best thickness for your first purchase. Try to get one with AR coating. Recently S8612 has been difficult to find. OR Schott BG39 x 2.0 mm OR B+W 039 S8612 has become difficult to find, so look for this next best IR-blocker for working in UV with a full-spectrum camera. Best Chinese ZWB and Other Filters: Tangsinuo Technology This currently reputable vendor recommendation is subject to change. UPDATE 9 April 2024: Recently a UVP member has reported that the thicknesses of filters received from Tangsinuo have not matched the requested thicknesses in the order. For example, one filter was .5 mm thinner than requested. Please INSIST when ordering that your requested thickness is supplied or else you will give Tangsinuo a bad review and file a complaint with Ebay. LINK to Review by JMC Please remember that Chinese manufacturing is not currently subject to the same standards which apply elsewhere. Striations, pits and visible leakage have been seen with some of the Ebay Chinese filter purchases. And some of the filters don't quite match the expected transmission in either peaks or rate. But these equivalents of UV dual bandpass filters and BG filters are very much less expensive than the high quality Schott or Hoya glass, so most beginners use Chinese filters to get started. FILTERS is continued in the next post.

What is everyone doing with their 8mm ZWB1

I've been playing around with building a UV microscope over the last year or so in between paid work (thanks Covid), which has been a fun build but very challenging. Most of my work with it is on sunscreens for a client and I cannot share those images yet, but I thought I would share a couple of of quick images of a diatom, from a Diatom Lab 2.0 test slide (see here - http://www.diatomlab.com/diatom-test-slide-version-2.0.html) The microscope is based on an Olympus BHB, and I've swapped all the glass in it for fused silica. In theory it can image down to about 250nm, but I'd need different camera/filters/light etc to get that low. With my setup I can image down to 313nm. I used a 100x NA0.85 Zeiss Ultrafluar objective, with glycerine immersion, and imaged using a monochrome converted Nikon d800. The images are stacks for 5 individual photos. The images were 'cleaned' (although looking at them now, not very well I hasten to add) and sharpened, but treated equally. The test slide mounting media lets some UV through, but is only good for 365nm (it is pretty much opaque below that). So I did visible (filtered 546nm light) and 365nm from a mercury xenon lamp. I thought I'd image Diatom 3 from the slide, which is Gyrosigma reimeri, and has about 18-22 longitudinal striae per 10um, or in other words about 500nm per striae. This is a severe test even for a high magnification, high NA objective, so should give my home built microscope with a 100x NA0.85 a real challenge. UV transmission microscopy was first developed in the pursuit of resolution, as resolution is directly related to wavelength. As such I expected the UV image to be higher resolution. Firstly, the visible image (546nm). This is the whole frame of the image. In visible light the striae are barely visible, but can just about be seen in the middle of the diatom. Secondly at 365nm, again as a full frame image. At 365nm the difference is pretty striking and the striae become visible. Cropping the 365nm image gives the following. Counting the striae gives 9 over the 5 micron distance or about 18 per 10 micron which is in keeping with the quoted number from the maker of the slide. It's a shame the mounting media in the test slide blocks the shorter wavelength UV, otherwise I'd try it at 313nm as well.

Some time back I got two new filters: Ulf's ZWB1 x 8.0 mm 325fwhm75, LINK1, LINK2 UVR Optics UVBplus 331bp75 I finally was able to test drive the new filters and thought I'd show you some results from photographing a little flower near our house. This flower is a Houstonia rubra. Flowers in that genus are commonly called Bluets, because they are blue (yeah...). I thought it a bit funny that this Houstonia's common name is Red Bluet. It was interesting to see this pincushion of rosy flowers popping up in the middle of all the sandy dirt. I actually carried water to it a few times to try to keep it going during the heat wave, but it's gone now. I hope it reappears next year. For all photos, white balance was measured on Spectralon. Visible: f/11 for 1/125" @ ISO-100 Baader UV/IR-Cut + B+W BG38 on UV-Nikkor Here are two reference reflected UV photos to compare to the photos from the new filters. Both the Pink Bluet's flowers and leaves are very UV-absorbing. But the plant does stand out against its background. UV: f/11 for 1" @ ISO-400 BaaderU on UV-Nikkor The KolariU photo looks almost the same to me as the BaaderU photo. UV: f/11 for 2" @ ISO-400 KolariU on UV-Nikkor Now the photos from the two new filters. UV: f/11 for 2.5" @ ISO-400 UVBplus 331bp75 on UV-Nikkor I'm not entirely sure, but there might be a bit of flare from this one. UV: f/11 for 3" @ ISO-400 ZWB1 x 8.0 mm 325fwhm75 on UV-Nikkor

I did a few series oftest shots to compare my ZWB1, 8mm with my U-340, 4 + 4mm - stack to see if my 8mm filter was flawed. Both filter sets were OK in that respect. However I was disturbed by the difficulty of WB those shots. my camera is a full spectrum modified Sony A7III where both dust-shaker and BG-glass has been removed. Jonathan (JMC) has earlier showed that the sensor's protective window do mot give this camera a very deep UV-reach, making it usable for exploring UV-B. So far this has not given me any problems as I am not into such more extreme UV-photography. It works quite well for UV-images including the false-yellow colour band. For the filter test above I used my EL-Nikkor 80mm lens that is one of the better accidental UV-capable lenses. The UV-reach of this lens is normally greater than needed and many lenses with less reach work well too. As I had problems doing a proper WB I decided to redo the test with a lens that has a really good UV-reach down to 200nm. I tested with my 70mm fused silica PCX-assembly and found that lens gave images that was easy to WB in a normal way. My FS PCX lens element is uncoated and has a transmission similar to the graph under the "Graphs"-tab on this page: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=123 Here are some images selected from my tests. they are jut screen shots from FastRawViewer after WB at the roof surface in the foreground. ZWB1, 8mm on EL-Nikkor 80mm old metal type ZWB1, 8mm on PCX FS 70mm assembly ZWB1, 8mm on PCX FS 70mm assembly, 100% detail:

MidOpt developed filters specifically designed to be less sensitive to light angle, for imaging with wide-angle lenses. https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://midopt.com/stabledge/&ved=2ahUKEwj2jq602uWEAxVGYPEDHYBiDGoQFnoECA0QAQ&usg=AOvVaw1H93yFqN96EJ4CIiXMqu6_

Last month I noticed "UV Pass Filter for Venus Photography" listed in the Tamgsinuo pages at AliExpress. I ordered one in 30.5 mm size for 59€. It arrived last week. It is an interference filter with a different coating on each surface, the reflections looks rather different to the BaaderU. I did a preliminary measurement with the old spectrophotometer in the lab at work, but the very old PC refused to let me download the data (dirty head in the diskette drive, most likely). So I only have the spectra photographed with the phone. To me UV transmittance looks very good, but it does leak IR at around 750 nm, and a bit at near 900 nm. The drop at the right end of the curve starting at around 1000 nm is not an IR leak but the limitation of the spectrophotometer as it looks exactly the same with different filters, the OD 4 roof is also a limitation of the old Agilent 8453 diode array spectrophotometer. Once I get the diskette drive cleaned (cleaning diskette ordered yesterday) I will post proper plots. Plot at the top is spectral transmittance (%) and plot at the bottom is absorbance (= OD) from the same data.

Thinking about sending the Pentax K1 full frame in for full spectrum conversion. Later I would purchase a second one for vis work. Ran across this clip in filter. This turns a converted camera back to "stock". Love this idea. Carry one body an do all types of photography. Anyone ever use one? Astronomik L-2 UV-IR Block Clip-Filter Pentax K-1 excl. VAT (Non-EU): €116.81 incl. VAT (EU): €139.00 Thanks, Doug A

Aye up lads! I have been attending this forum for a while as a reader, and following your discussions on how to imitate Aerochrome film in digital. This is clearly not what this post is about, although it put me on the right way to find out how to obtain a DIY version of Kolarivision IR Chrome filter. I would say it has been a mix of trial and error plus some rudimentary investigation on colour wavelengths. The filters tested are the chinese QB2, QB3 and QB19. A chinese factory was selling QB2 as the cheap version of IR Chrome, but QB2 is far from any resemblance by itself. They even stole Kolarivision photo from the website to promote the QB2. The QB2 toghether with a GRB3 or KG3 from the same retailer made some difference, but still not good enough. The leakage of IR was still too strong. The tests I did with only visible light showed too much red and yellow overall. So the amount of light transmited around 500nm to 700nm was still too much compared to IR Chrome. On the images below you can see the original colour pattern I created followed by Kolari vs. QB2 vs. QB3. All photos taken with a non-sensible NIR camera. So there is no possible NIR leakage in them. QB3, as you can imagine, is far from any resemblance with Kolari's. The final image is too blueish. Although its wavelength is quite similar to Lee 729, I couldn't manage any similar results. I must say, my QB3 is just 1mm, I will come back to this later. I saw this QB19 filter after a while, which looked somehow in between QB2 and QB19. QB19 filter is really similar to QB2, but cuts blues at 325nm aproximately. Also, does not allow that much light from 500nm to 700nm as QB2 does. I will let experts from this place to debate on it. I am not a physicist, so I am afraid I'd say some stupid stuff. My QB19 filters are 1mm and 1.5mm. Toghether with them, I tried GBR3 or KGB3 from the same retailer. These are 1mm and 2mm thick. Right now I am using 1:1 ratio. So same thickness on both filters. The good thing about using 1mm filters is that I can use one single ring for my super wideangle lenses. Below you can see the results SOOC from a Fuji XT10 with 10-24mm and 15-45mm lenses. The order is as follows: Original scene (no NIR). Kolari IR Chrome. QB19 + KG3 (True Color SR). 1:1mm QB2 + KG3 (True Color 550nm). 2:2mm QB3 + KG3 (True Color SB). 1:2mm The slight difference you can see between QB19 + KG3 and Kolari's is due to adjusts made on camera white balance. I did not have a WB card, so I had to do it by visual approximation. A bit more green on the camera would solve the problem. QB2, as you can see has a bit too much red, this bothers a bit when editing and makes it hard to preserve the warm-orange-red tones from the vegetation. This combination, QB2 + KG3 is really nice to make golden vegetation. The following images are in the same order, but the WB preset is a bit different. I will keep posting some more images to compare True Color SR and Kolari's filter. Disclaimer: I really appreciate Yann's work on IR Chrome, and this post is not by any means trying to discredit his work. In fact, I got inspired by his dedication to IR light and this is what took me here! ;)

Warning: UV-C is dangerous. Eye and skin protection is needed ! I am looking for Constructive Critique for this UVC 260nm Illuminated photo. I have tested these lights with filters & a filter on the lens & the my spectrometer shows NO IR contamination with this combination, the light band is quite narrow. The camera is a Full Spectrum with CFA intact, Sigma fp camera & a UV Nikkor 105mm lens, with a 2 second exposure time. Considering all restrictions I think this is a reasonably short exposure time. Increasing the wavelengths I am able to decrease the exposure times accordingly. I know I am pushing the limits, but I wanted to see if it was possible, without being totally ridiculous. I could get a de-Bayered CFA camera for pure mono images at shorter exposure times. I just wanted to see what was there. I have copied Lou Jost setup, for no reason but it is somewhere to start. A glass flask with water & an aluminium foil inside, a PTFE screen is behind.

Emulating Aerochrome is a long and winding road. Anyone who has read my previous posts on Aerochrome has probably seen my frustration in achieving an authentic look. Now I am back with the Foveon (Sigma SD1 Merrill) and have tested with the Triple Bandpass. And suddenly I achieved an in-camera look that is actually not bad at all. The magic phrase is FOV Classic Blue. This is an in-camera preset that exists in the Sigma SD1, like “neutral”, “landscape” and so on. What it does? I don’t know. Like much else about Sigma’s Foveon sensor cameras, it’s a black box. But in any case, it results in getting red-pink trees and green-blue skies right out of the camera with the Triple Bandpass filter from Midwest Optics. The color changes were unfortunately not there yet, with the exception of yellow to white. But red was still reddish, or let’s say at least orange. But if you install an additional filter that flattens the transmission curve of green (in the 550nm range), then it becomes good. Why? I do not know. The best result I got so far was with magenta/pink filters from Lee. Here are some results. Unfortunately I did not get a Custom White Balance with both filters together. That would be necessary to get a convincing result. It's not perfect yet, the color changes aren't optimal yet, as well as the coloration in the vegetation, but I think that's a big step forward towards authentic Aerochrome SOOC.

Here is a look at how my dual bandpass filters look when used with no additional IR-blockers.These filters transmit both UV and IR. However, when used outdoors in sunlight the amount of UV and IR hitting the sensor lens is approximately in the ratio of 1-to-17 UV-to-IR. So even after accounting for the higher transmission of UV over IR by these filters, to me the resulting photos look very much more like IR photos than UV photos: skies are dark and foliage is bright. I have no problem labeling them Infrared photos. Some people disagree with this. That's OK. Edit: Correction of typo above. Edited statement to add "to me". Added: In response to a later comment, I note that examination of the transmission charts of these filters shows very minor transmission of violet and high red visible light for some filters. The scene is a backyard snowscape with lots of detail. I'm going to show you the pretty converted & edited versions first. Then maybe we can look at the Raw Composites to see how these filters are causing the light to be recorded. Equipment: Nikon D600-broadband + Coastal Optics 60/4.0 + Sunlight Exposure: f/8 for X" @ ISO-100 REFERENCE PHOTOS Visible: Baader UV/IR-Cut Filter for 1/1000" Infrared: B+W093 IR-Pass Filter (830nm) for 1/200" Ultraviolet: BaaderU UV-Pass Filter for 1/15" SCHOTT UG GLASS Please note that my filters are not all of the same thickness. So we should not be judgey about exposure times or edited false colours. This is meant to be a simple, informal look at how these filters record. White balance was made on the same location in all photos. The same colour tweaks were applied to each photo. UG1 (1.0 mm) for 1/125" UG5 (1.5 mm) for 1/320" UG11 (.75 mm) for 1/125" HOYA U GLASS Please note that my filters are not all of the same thickness. So we should not be judgey about exposure times or edited false colours. This is meant to be a simple, informal look at how these filters record. White balance was made on the same location in all photos. The same colour tweaks were applied to each photo. U330 (1.5mm) for 1/250" U340 (1.0 mm) for 1/100" U360 (2.0 mm) for 1/40"

[UV SAFETY] UV-C Light Is Dangerous NEVER look at a UV-C light. NEVER let UV-C light hit your skin or eyes directly or by reflection. UV-C light can cause: severe burns of the eyes and the skin, and DNA damage from broken chromosomes. When working with UV-C illumination, you MUST: cover up completely, wear head & eye protection, and have strong ventilation. Hi, I know this was asked in other threads, but can we make some kind of summary about available UV-C options? To be honest, I can't even find one best light source & filter for this, so I think such kind of topic is needed. I know that there are UV-C light sources like: - low pressure Hg lamps (but are they enough to photograph with, can we have a summary about a distance they are able to lighten so any picture can be made?). - excimer lamps (like 222nm) - aren't they too weak to do any photo with them - I see only input powers but not actual UV-C output when shining at anything from, say, 50cm away? - others? Regarding filters or stacks - I literally find no option. Every filter I see is either just a band-pass filter that only passes 20nm width around some UV-C frequency and then has IR leaks that would make it useless, and if you want to block IR with S8612 then no way - S8612 and similar block UV-C). So I can't find any usable filter, not even speaking about having it in 52mm thread or any similar, they are usually tiny, specific for some laser etc. So can we list possible, most powerful UV-C light sources and possible (if any) filters?

So I ran into this on Ali, I would say it's rather expensive but as far as filters go, it's pretty normal. But as far as Ali sellers go, it's quite pricey for sure. It's supposed to be holmium oxide glass, what would this be used for? And what effects do you guys wager it would have on a full spectrum camera? https://a.aliexpress.com/_mPqyZKF

These days I was considering buying some Chinese filters to replace the Jena Glass BG25 and BG18 that I broke. I have seen that Tangsinuo uses Optima charts from the Optima website (optima-usa.net/80). I downloaded both the graph and the PDFs. There are big discrepancies. Do any of you have QB5 and QB29 and measured them? I was excited to use the QB5 (yellow line) instead of the QB29 + QB39 stack to emulate collodion - wet plate. Thank you - Toni GRAPH .PDF

In the introduce yourself area a discussion broke out about Baader Venus U filters. I think this deserves its own thread for discussion as it always seems confusing how many different versions there are. I bought mine new from Company 7, located in the USA, back in October 2008. At that time it was called the new version. On the side it says: Baader U-Filter 2" (HWB = 325-369nm) Optically polished #2458291. Its greenish yellow on one side and redish magenta on the other. Label: Green side: Red side: Transmission spectrum recorded when I worked in a lab, back in Sept. 2009: Absorbance spectrum recorded back in 2009: Would be great to know what the most recent ones look like as you can see from my image it cracked and fixed with tape. I still do like the contrast from this UV filter the best. Too bad its not available in 25mm.

I have recently joined what seems to be a new wave of people buying the Sony DSC-F828 2003 point and shoot camera, mostly due to its one of a kind sensor and extremely easy full spectrum conversion. I have been very curious what UV looks like with this camera, given its RGBE sensor. I have only obtained a fitting magnet to flip out the hot mirror filter last evening so there was no time to do UV under natural light. I got to do it now, though. The image is in full resolution, so feel free to click and enlarge. ZWB2+QB39 Tangsinuo stack 3s exposure, ISO 64, f/2.5 These flowers are UV yellow, yellow in real life as well. They're about as UV yellow as gerberas or dandelions. Here they are a very desaturated shade of orange. I think it's due to the fact that the Zeiss T* Vario-Sonnar 2-2.8/7.1-51 zoom lens does not pass much UV at all. That is to be expected, but still a shame, since this sensor could have unlocked a lot more UV false color, given its 4 color channels as opposed to the usual three. Last observation: flipping out the hot mirror seems to make the image only marginally brighter, meaning the hot mirror either does not block much UV at all or the lens passes so little most of what does pass is around a wavelength the hot mirror was not designed to block. Either way, I am happy I have this camera now, the IR results have been a lot less underwhelming, and even the normal visible photos have an interesting look to them, very much unlike the images taken by modern cameras. At the risk of sounding like a huge cliche, they do look somewhat film-like color wise. Probably since back then, digital was still considered to be a replacement for slide film (and was designed as such), not a universal best way to record anything.

As you know, all cameras react differently to IR light once they are converted to full spectrum. I don't know if this is really well understood so I wanted to start a topic and have your opinion about it. I just got the Sony f828 (the camera that can be converted to full spectrum with just a magnet) and I can now compare its fullspectrum colors to my Canon. Canon 1200D, white balanced full spectrum colors, no additional filters : Sony f828, white balanced full spectrum colors, no additional filter : The pictures were white balanced and saturated from the RAW files in Lightroom. The two cameras are pretty far apart as we can see from these pictures. They are also pretty far apart in terms of technology : the first is an 18Mpx CMOS and the second is a 20 years old 8Mpx CCD one of a kind RGBE sensor. Sony camera are known to not perform as good as Canon with the IRchrome filter. The images above indeed show that this Canon camera has a predisposition to record IR in the red channel compared to the Sony. Now do more recent Sony cameras produce blue SOOC like this one does ? I don't know... Maybe the sony users here can help me from their experience.

Hi. Since i´ve already got my piece of PTFE board to correct the WB on camera, I decided to do some tests with my filters. Shots are sooc. Camera is the Panasonic Gf3 (full spectrum converted). Comments are welcome..... 1-minolta R59 (red) 2-minolta O54 (orange) 3-minolta GO (green) 4-minolta Y48 (yellow) 5-Toshiba R60-2 (R2) (red) 6-Kenko YA3 SO-56 (orange) 7-Hoya G(X1) (green) 8-B+W 48 GG 2X (yellow) 9-olympus sy48-y2 (yellow) 10-B+W 49 B12 3x (blue) 11- FL-D 12-Hoya Vario PL-Color R/G (red) 13-Hoya Vario PL-Color R/G (green) 1-Minolta R59 (red) 2-Minolta O54 (orange) 3-Minolta GO (green) 4-Minolta Y48 (yellow) 5-Toshiba R60-2 (R2) (red) 6-Kenko YA3 SO-56 (orange) 7-Hoya G(X1) (green) 8-B+W 48 GG 2X (yellow) 9-Olympus sy48-y2 (yellow) 10-B+W 49 B12 3x (blue) 11- FL-D 12-Hoya Vario PL-Color R/G (red) 13-Hoya Vario PL-Color R/G (green)

In our list of recommended gear, LINKIE, I have of course listed the following stacks. ZWB1 + QB39 ZWB2 + QB39 ZWB3 + TSN575 But I don't know anything about the typical thicknesses of ZWB glass sold on Ebay. Also, does anyone have any recommendations for thicknesses of the IR-blockers? I will try to investigate on my own, but would also welcome any input from folks actually using ZWB stacks of any kind. Thank you in advance.

Does anyone know if this exists? An "inefficient" hot mirror, but one that is not working in the 700-750nm range, but further back, ideally starting at 900nm? I ask because I think such a filter would be much better for Aerochrome emulations than others. As you may know, there is the Triple Bandpass Filter from Midwest Optics, which allows IR around 850nm to pass, in addition to red and green. Pretty good for Aerochrome variations, but still not good enough for me. I recently tested with a DB940nm, which passes the full visible spectrum plus IR 940nm, and had better results. I thus tried to make a "TB940" by additionally using a specific orange as well as a specific blue filter to get the two peaks at green and red. The result was - SOOC - a lot better than with the triple bandpass. I think you could create the perfect Aerochrome filter. Sure, it wouldn't be SOOC (not possible), but it would be one which creates a SOOC image that can be turned into the perfect authentic Aerochrome image by a simple channel mixer change. Blue (IR) -> Red Red -> Green Green -> Blue Hence the question posed above: does anyone know of a hot mirror that allows IR to pass from 900nm, 950nm?

Hello, Firstly I apologize for being not a very active member here (photography outside the visible range has been a bit on hiatus)... I've created this topic because I currently struggle about making a choice for a deeper IR Longpass filter. It is also fueled by the recent availability of more cut-off wavelength choices from Kolari Vision with addition of KV780, KV930 and KV1000nm filters. I already own a B+W 093, but the diameter seems too small to cover most options, and it is also leaking some visible reds (can be an issue for long exposures). By looking at the transmittance curves on their site and the forum, the Kolari 850 seems very similar, almost identical to Schott RG850 glass. Their 1000nm filter is also tempting because I believe some more pronounced effects can be achieved (like even more darker skies with unique contrasts and water starting to darken). However the transmittance curve is currently not available, with risk of leakage (unlike RG1000 glass), and I fear that the filter's lesser flexibility regarding exposure times will counteract the gain from more pronounced effects. I am also tempted to cut the pear in half by choosing their 930nm, but again the transmittance curve is not available,and there is a possibility that the filter could be a bit leaky in the visible such as the Hoya RM90 or the B+W093(RG830). So far hesitation comes between : - RG850/KV850, the former being difficult to find in my country - RG1000 (maybe KV1000 ?) - secondarily KV930 What are your experience with filters having similar cut-off wavelengths ? Which one of these would you recommend ? Best Regards,

Hello, my name is Fedia, I'm 31 and I spend lot of time creating images through digital photography. I'm stoked to be able to join this forum since it has been an incredible ressource without which I couldn't have developed the techniques I use today. I have talked to some of the people of this forum on other platforms, used their advice and want to thank them also. I've been doing photography since 2014 when I entered film school. I got my first full spectrum camera in the fall of 2020. Even before I got into full spectrum photography, the main thread I explored was color, that I achieved through filters or extreme white balance settings on regular cameras. Even today with full spcetrum photography I don't really use softwares. I try to do everything in camera. Therefore I exclusively shoot jpegs and only work contrast in Lightroom. I never opened Photoshop. I am a big technical nerd I guess you could say, but the truth is my relation to technicity has a lot to do with my artistic sensitivity, both are entangled. I have a lot of ideas of subjects to discuss on this forum so I will post about them in the near-future. But for now I figured I will post some of my photos to introduce myself. Every one of the following photos are the result of a different filter combination with no color processing outside of the body of the camera. I will precise the camera and the filters each time. Canon 1000D full spectrum + Lee "CID to Tungsten" Canon 1000D FS + Lee "loving amber" + db850 Canon 1200D FS + DB850 + Lee "Liberty green" Canon 1000D + unknown dark pink gel Canon 1000D + Lee "steel blue" Canon 1200D FS + Lee "peacock blue" + GRB3 Canon 1200D FS + hoya 80A + hoya x(0) + cokin 089 (warm diffuser) Sigma DP1s FS Sigma DP1s FS + Hoya 80C Sigma DP1s FS + GRB3 Bonus : Sigma DP1s FS no filter. If you want to see more I have an instagram : https://www.instagram.com/fedialebarboc/?hl=fr And a tumblr : https://fedialegrill.tumblr.com/ Thanks again, Fedia.

I've noticed something now working with my Hoya R72 filter. Using a modified camera or not, when I push and pull too far, I get this odd blotchiness in certain sections. Can anyone comment on what this is? I've been told it's related to wavelengths.