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Good evening! In addition to the quick test of the new Kolari Vision UV filter, I have bought 3 new lenses including the Steinheil 50mm F/2.8 EDIXA Auto Cassaron. Until now I was using the Nikon E 50mm F/1.8 and sometimes the Yongnuo 50mm F/1.8, so I have decided to make a comparison of these three 50mm lenses I have for portrait photography. For this comparison I used 3 Yongnuo yn560 IV unfiltered at full power, the same camera distance (1m) and the same EXIF : 50mm, F/5.6, 1/40s, 400iso. The focus is not perfect at each time... After the take of the shots, each file was processed the same way. Note : the shutter speed is not a real parameter here because the only UV light source is provided by the flashes. It only has to be lower than the synchronisation time of the flashes : 1/200s. Here are the results of the test : Yongnuo 50mm F/1.8 Nikon E 50mm F/1.8 Steinheil 50mm F/2.8 EDIXA Auto Cassaron As you can see, the Steinheil 50mm F/2.8 EDIXA Auto Cassaron has really great performance in ultraviolet photography : the exposure is twice better compared with the two other lenses. It is a bit less sharp but you can shut down the aperture to 1 or 2 more stops and keep having a good exposure. The Yongnuo is not really good, its only good point is to have auto-focus. The Nikon E has really great sharpness (not on this shot but in my experience) but requires a lot of UV light. As a conclusion, I think I am going to change the 50mm I use for the Steinheil 50mm F/2.8 EDIXA Auto Cassaron for my next project to have a really better UV transmission.

A video presenting the UV-Nikkor and some of its features and UV-photos

Editor's Note: The summary of protocols for the Pinhole UV Lens Test is found in Post #14. ****************** Recently our member Hornblende made UV pinhole photos of several lenses and member A.S. made BaaderU UV photos of several lenses. See these links: http://www.ultraviol...ikkor-80mm-f56/ http://www.ultraviol...of-some-lenses/ Earlier our member OlDoinyo made a UV pinhole test with a red/green channel swap. See this link: http://www.ultraviol...dpost__p__10955 I wanted to try this kind of test out of curiosity and also because I was puzzled about some aspects of testing UV transmission this way. I used my BaaderU UV-pass filter over a pinhole lens cap. Gear Nikon D610-conversion Spectralon Pinhole Lens Cap BaaderU UV-Pass Filter Method Remove all adapters and step-rings from each lens and open it to aperture 4.0. Carefully balance the lens on a filter box (!) so that the lens mount end is 2" from the Spectralon slab. Shoot exposures of 5, 10, 15, and 20 seconds through the front of each lens. I used that series of exposure times because I wasn't really sure how long make each Pinhole exposure. Maybe next time I can settle on just one exposure time? Note that the chosen exposure times are not the same number of stops apart. Maybe next time, I'll fix that, too. :) Each exposure was converted and white balanced but no edits were made. Crops and resizes were made in Photo Mechanic. The Lenses There were five 135/3.5 lenses sitting in the UV cabinet which I had never gotten around to testing last year. So they were perfect candidates for this experiment. The 135mm length is generally considered a portrait focal length, but I enjoy 135s for other types of shooting too. Asahi Optical Co. Takumar 135/3.5 M42 Hanimar 135/3.5 T2 Kyoei Optical Co. Super Acall 135/3.5 M39/M42 Lentar 135/3.5 T2 Petri Orikkor Kuribayashi 135/3.5 (Not sure of the mount - Petri? or M42?) The Chart I am assuming that we can conclude from the summary photos on this chart that the Hanimar is the worst of the lot for UV transmission because it shows as dark blue? And the other four have more or less the same transmission because of a very pale colour? What I don't understand is whether we are looking for the presence/absence of colour when photographing through the lenses or whether we are looking for relative lightness/darkness between any two lenses?? Typo: I labeled the Kyoei 135 with W. Acall instead of Super Acall. Sorry about that! I've had the Kyoei 35/3.5 W. Acall for a couple of years now, so that name popped out when I was making the chart. I will try to get the label fixed later. ADDED LATER: I've let you see all the errors I made along the way as I worked out how best to perform a Pinhole Lens Test. I think that it's important to know that these kinds of informal tests can go astray in various places.

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..

First things first: UV photos: EOS 6D, b/w maxmax-conversion with 330C and S8612, Soligor 21mm VIS photos: EOS 5DSR, Canon EF 11-24mm IR photos: EOS 6D, 700 nm conversion, EF 16-35mm and 11-24mm Due to these differences, the angle-of-view is different, also I took some of the UV-photos on a different day. The first sets of photos were taken at a church nearby (https://de.wikipedia...St._Margarethen). It is amazing, how repair works at the walls can be all but invisible in IR and VIS, but hit you over the head with a mighty big hammer in UV: Next, the colours used in painting buildings, especially the yellow found on plenty of churches, don't always show up in IR and UV, also the huge golden crucifix is rather boring in IR and UV. With the next three, I cheated a bit, as they were taken from the church, overlooking the danube, so not quite a photo of ecclesiastical (Yes, I had to look up how to spell this word) architecture, but there's cross in it, so it counts sort-of. I converted all photos to b/w, just to emphasize the differences (the UV-photo was taken from a triped, as there was not enough sun) The last set was taken at a monastery (https://en.wikipedia...Wilhering_Abbey , I tried some photos in the church of the stunning colours but both IR and UV are just dull, of course). The pink/brown/salmon colour used here does show up in IR and UV, which might also mean that they used different materials here than in the white parts. Bonus photo: the chapel does not look very nice in IR, but I like the colours and the lines.

Yesterday I was tutoring a student and my phone rang. It was my landlord, so I told my student to hold on, I had to take a call. My landlord, who I’ve always been on good terms with, sounded unexpectedly hesitant, but he told me he was cleaning out his house, trying to declutter, because he didn’t want his kids to have to deal with it all at once if he died (he said he wasn’t planning on dying soon, but at 80 he better get started cleaning up). It turns out that he found a ton of old camera equipment and would I like any of it? THAT offer was snapped up quickly! So today he dropped it off and I’ve started trying out lenses. This Nikkor 50mm F2, used for the photo here, was an especially nice one. This was on the NEX-7 (APS-C) with 1.75mm S8612 + 2mm UG11. (After sharpening in my usual way.) F/8 2.5" ISO100 1:1 Crop, SOC:

There is a Focotar-2 50mm for sale on eBay to a very nice price: https://www.ebay.com...ZIAAOSwUp1gHP7E It is only available for delivery within EU. I already have one of those lenses and do not need to hoard another. The Focotar-2 50mm has a very good UV-reach. See my relative transmission measurement (the dark magenta curve): https://www.ultravio...dpost__p__18699 This lens is on my list for an entry in the UV-Lens Data section eventually

Following Andy's post comparing El Nik 80 & Cassaron, here are some comparisons I did recently. These finally persuaded me that the Focotar 2 was better than the Cassar S for a 50mm UV lens. The Cassar S seems to perform better in UV than it does in visible. The top row is a crop at centre of the image - the area shown is approximately 1/30 of the full image width. The middle row is at extreme corner (APS-C sensor) with no re-focusing - the area shown is about 1/35 of the full image width. The bottom row is extreme corner with refocussing. The set of rings at the centre was different to that at the edges. The difference betwen the middle and bottom rows gives an idea of curvature of field issues. In all cases, the camera was moved for the various focal lengths to give approximately equal image sizes. The 345 nm and 850nm images were made to give a narrower wavelength band than the Baader U and R72 images and reduce the effect of chromatic abberation. All exposures were f/8, ISO 100. The lenses used were: Canon EF STM 50mm f/1.8 Steinheil Cassar S 50mm f/2.8 Leitz Focotar-2 50mm f/4.5 El Nikkor 80mm f/5.6 (old-style metal) El Nikkor 105mm f/5.6 (old-style metal) Igororiginal 35mm f/3.5 Canon EF 28mm f/2.8 Visible: Baader U: 345BP25 filter: R72 filter: Midwest Optical BN850 filter:

Lens test of the Nikon EL-Nikkor 80mm/5.6 metal version vs. Steinheil München EDIXA-Auto-Cassaron 50mm/2.8. This was a pretty casual test -- I just slapped each lens on the camera (Sony A7S mark 1, full spectrum) and took a picture with each lens with the same settings. It's not quite apples to apples because the focal length is not the same for the two lenses, but it gives some idea of the performance you can expect, at least from MY copies of these lenses. (As we have seen, Bernard says his Edixa is much sharper, and I suspect David's is even worse than mine. But at best we have HIGHLY variable quality from the Edixa, whereas most people report good things from the EL-Nikkor. Bandpass is similar for both I think, but maybe Ulf will have to test the Edixa to compare that.) Lens pics: Settings: F/8, ISO320, 1/4" for both lenses. White balance in-camera off the street in a sunny spot using the EL-Nikkor and then not changed after that. 1.75mm S8612 + 2mm UG11 (both from Cadmium, so definitely not Chinese) Bear in mind that the Sony A7S is a full frame camera (35mm) with 12 megapixels, so your own performance will vary -- if you have a 50 megapixel full frame sensor or something, you will see all the problems shown here but even WORSE. The camera was balanced on the windowsill for the test, and I used the 10 sec countdown setting to avoid shaking the camera. First, the whole images, resized to 1100px width. EL-Nikkor 80mm ( Ignore the tree blur, it's inevitable at 1/4 second exposure): Edixa-Auto-Cassaron: Now a crop and resize to 200% from the center of the frame. EL-Nikkor 80mm (left) vs. Edixa-Auto-Cassaron (right): Bad chromatic aberrations on the Edixa! And that's in the center at F/8. Now the corner (I used the same exact pixel locations for the crop in both images.) These are 1:1 crops. EL-Nikkor 80mm (left) vs. Edixa-Auto-Cassaron (right): I trust that everyone can understand now why I am so negative about my Edixa-Auto-Cassaron!

Revised Post to include larger screen shots of my spectra to see the axis and curves. I also provided images of the lenses. Note All spectra below are only for cut off determinations ONLY. The absolute transmission was not corrected and the curves do not represent that. Just look at were the curve ends into UV. I don't have an integrating sphere. I am posting this in case anyone was looking for a cheap lens for the HQ Pi camera. These seem to be good options for some UVA imagining: This is an image of our favorite Wollensak 25mm F1.5 c-mount lens with AA battery for scale: This lens will mount to HQ and m43rds and focus to infinity without any modification. The front filter thread is 25mm. Full screen shot of a revised spectrum collected Sept. 9, for the Wollensak 25mm F1.5 C-mount lens: Image of a Computar 8mm lens: This lens will mount and fully cover the HQ sensor. It will mount to m43rds camera, but the image circle reaches the horizontal frame (Black corners), it may focus to infinity if the mount is modified, I haven't modified mine but have seen some whom have had success with specific Cmount adapters. The front filter thread is 40.5mm. Full screen shot of Computar 8mm C-mount lens: Image of Computar 12.5mm f1.3 lens front: Image of Computar 12.5mm F1.3 lens side: This lens will fully cover the m43rds sensor and if you shave off a bit of the mount it will focus to infinity on m43rds camera with selected Cmount adapters. lots of talk about this lens online as cheap alternative to the Olympus lens. The front filter thread is 43mm. Full Screen shot of Computar 12.5mm F1.3: Image of Cosmicar 16mm F1.4 C-mount lens: This lens will mount and fully cover the HQ sensor. It will mount to m43rds camera, but the image circle reaches the horizontal frame (Black corners), it may focus to infinity if the mount is modified, I haven't modified mine but have seen some whom have had success with specific Cmount adapters. The front filter thread is 40.5mm. Full Screen shot of Cosmicar 16mm F1.4 C-mount lens: Image of the small Arducam 4-12mm F1.6 zoom lens which covers the full HQ Pi camera at 4mm. This will also mount to a m43rds camera but there is no front filter thread and it will not focus to infinity at 4mm. The IR means its has been corrected to focus in IR and does not have an IR block filter: Full screen shot of the Arducam 4-12mm F1.6 lens at the 12mm setting on the lens: Full screen shot of the Arducam 4-12mm F1.6 lens at the 4mm setting on the lens:

Historically focal shift in lenses has been corrected by using two materials, a "flint" glass and a "crown" glass fused together. Thus we have UV lenses that use quartz and fluorite for example. The problem with this method is that any change in refractive index can cause reflections at the interface and there are always losses. It seems Edmund found a way to dodge the usual limitations of lens optics by developing some kind of custom optical formula that allows them to correct the focal shift using just the lens shape alone, without involving multiple materials. This leads to SINGLET lenses with low focal shift. Since UV lens designs with fewer elements always perform better, a UV lens with such a design would be ideal for us. Currently Edmund is only advertising their lens for use in the visible spectrum (and at $1000, not a very attractive price), but the technology itself sounds very promising. Here is their article on their new tech: https://www.edmundop...eric-achromats/

In the city of Mauthausen there was the largest concentration camp on Austrian soil during the Nazi regime (https://en.wikipedia.org/wiki/Mauthausen_concentration_camp). All Soul's Day would have been a fitting date to visit it, but I don't have time tomorrow, so I went today. I did not have time to take photos of the many memorials outside of the compound or the infamous quarry (see first photo on the right here https://en.wikipedia.org/wiki/Extermination_through_labour ), so I will go back there, but not too soon; the place really gets to you. The morning fog would have made for an eerie mood also with VIS-photos, but I do believe that UV adds to the sombre atmosphere, especially with the usual dark grass and foliage. Camera: Canon EOS 6D, converted to b/w, internal X330C-filter, external S8612 Lens: Soligor 21mm f/3.8

I have a copy of The Handbook of Photography (Nikon F, Nikkormat), by Cooper and Abbot (1968, 1st edn.) where two (?) further UV Nikkor lenses are mentioned: UV Nikkor Auto 50mm f/4, and a UV Auto Nikkor 55mm f/4 (I wonder if this is a typo and both should read 55mm?) . I have not seen mention of them anywhere else. Have anyone ever seen/used one of these, or even have one? They must be as rare as hen's teeth!

In the last few months I've made quite a few UV-photos with my EOS 6D, converted by MaxMax to b/w with an internal XNite 330 filter. Maxmax recommends an additional XNite BP1 filter to get rid of the 10% IR-leak. So, yesterday I shot a series of photos of my cemetery hill with plenty of different filters, IR, a few Chinese ZWB, bug-vision, bee-vision, etc. just to get a feeling for them. So far, so good. However, when I did the comparison shots without any filter (i.w. only the 330), and with the BP1, I could not detect any significant difference. Judging from the photos in visible and infrared, there was a tremendous amount of infrared present, which should have killed the UV-look in the photo without the BP1. I am at a loss what went wrong. Either the filter transmission chart from Maxmax is not correct, or I did something really stupid. Any hints welcome Here are the photos: First visible (half of the frame is in the sun): Next, Infrared 700 nm (quite a lot of it): 330 + BP1 (supposed to be ultraviolett): 330 (supposed to be some ultraviolett and huge amounts of infrared): For completeness sake, BP1 only (taken with my full-spectrum 6D):

The Novoflex Noflexar 35mm f/3.5 was popularized a while back which led to complaints about the price going up to unreasonable levels. But recent prices on the US Ebay site seem to be more reasonable even if not actually cheap. The last three bid (as opposed to buy-it-now) sales were at $99 (one bid at starting price), $150 (one bid at starting price), and $128.50 (15 bids from a $9 starting price, which I won). I'd consider the last of these to be the most representative due to there being a true bidding contest. As always, there will continue to be grossly overpriced buy-it-now listings and a few people will fall for those.

I while ago I picked up a 25mm Zeiss Luminar lens, which turned out to the quite a nice UV macro lens (written about it here - https://www.ultravio...dpost__p__35273). A little later I also got a 100mm Luminar, which was not that good in UV, which is also shown in the above thread. A few days ago I was offered 16mm, 40mm and 63mm Luminars, so I thought why not complete the set. Here they all are; And here are my measured transmission plots between 280nm and 420nm. I think the 16mm, 25mm, 40mm, and 63mm ones are Version 1 lenses, based on the descriptions in Enrico's site. The 100mm is I believe one of the later ones. The 16mm and 25mm ones are marked with an * in the graph as the apertures for those are very small, and I suspect might be clipping the light beam slightly during the measurement. Therefore the absolute transmission for those are likely slightly higher than in the graph, bringing them in line with the other three. Some interesting characteristics; The 25mm one is the best in terms of how far in to the UV it transmits, and the 100mm is the worst (and I think my version of the 100mm is the 3 element one). The 16mm one is the 2nd worst. This has a relatively complex lens design so its behaviour makes sense (5 elements, 4 groups). The 40mm and 63mm did not behave as well as the 25mm, although they have fewer elements (both 3/3 vs 4/3 in the 25mm). Overall, the 16mm to 63mm ones all look to offer a good to degree of UV transmission especially for UVA imaging, so I'll definitely be using these in future for macro work. They also fit my microscope and throw a huge image circle, so will use them for some microscopy too. I went into this assuming the 40mm and 63mm would have better transmission than the 25mm given their simpler designs. Just goes to show that it's hard to predict lens behaviour in the UV.

Just a quick shot of unidentified crustose lichens that can be found everywhere on old stone drywalls on the island of Öland. They form visually featureless flat crusts that are white also in VIS in the dry state. They become somewhat less VIS-reflective when wet, but I have no comparison shot. Mosses and other lichens on the same stone surfaces, in contrast, are UV-dark when dry. My guess is that, as far as UV is concerned, either absorption or reflection of UV in the surface layers is a good adaptive strategy to protect the living tissues underneath. In the VIS and NIR, a reflective (or white) surface could also be adaptive in lowering the temperature of the tissues during periods of high solar irradiation. Full-spectrum Sony A7 II, Baader U, AI Nikkor 24 mm f/2.8. Somewhat underexposed to avoid saturation in the white areas.

I've been exploring the world of microscopy more recently, and of course wanted to do some UV microscope images. The image below is a sunscreen product - an oil in water emulsion, with the UV absorbing ingredient in the oil phase - on a microscope slide, lit with a Xe lamp and imaged with a UV converted Nikon d810 camera. Overall magnification about 400x, so the oil droplets start at under a micron in diameter. The oil droplets contain the sunscreen, hence look dark. I've written up more about it here - https://jmcscientificconsulting.com/uv-microscopy-of-sunscreen-formulations/ - including a rather funky UV video of when the emulsion collapses and the oil droplets fuse together, filmed at ISO 10,000... Logistically it was not easy to do - the microscope needed supporting on a lab jack, to get the light port up to the same height as the output from my lamp. Cue the health and safety violations.....

This thread will contain any testing I do on the Carl Zeiss 60mm f4 UB-Objektiv lens (lens shown here - https://www.ultravioletphotography.com/content/index.php/topic/3942-carl-zeiss-60mm-f40-uv-objektiv-exakta-mount/page__view__findpost__p__36259). The lens is a triplet construction, and my copy is in Exakta mount. As I have an adapter for Exakta to Canon EOS, I'll be using this on my Canon and Sony cameras. If I get a Nikon adapter in future, I'll also try it on those. How does it behave in UV? Here's some initial test shots, taken on multispectral Sony A7III, using both the Baader U filter, and a combination of the Baader U and a 365nm 10nm band pass filter from Edmund Optics. It was a windy day but sunny, so I cranked the ISO up to 10,000 to try and spot the movement, and the exposure times were between 1/30s and 1/100s. White balanced in Darktable using a Baader U image of a PTFE disk. Pictures of Buttercups and my garden. Definitely some good strong UV rendering of the Buttercups with the lens. There's also some swirl in the background which reminds me a bit of the Helios 44 and 58mm Biotar lenses. When the focus ring is turned all the way to close focus, the lens shows evidence of some pretty horrendous light leak. Although this disappears very quickly as the focus moves away from closest distance. Shot below was taken at closest focus distance. As I do more testing in the future, I'll add to this thread with the results.

I was able to recently obtain a JAZ spectrometer with two modules to look at some UV and IR. I have been playing around with it to learn its many oddities. Maybe obvious things but things I have learned that affect the signal when trying to determine the transmission through a lens. 1. Most critical is the alignment of the fiber optics. This is obvious. As you slightly shift the optical fibers you will affect the light detected. 2. The path length seems to matter. As in, a longer tube will affect the transmission. I was surprised by this not being negligible. But makes sense, more air between the fibers increases the scattering of the light, which decreases your signal. 3. Orientation of the lens matters. If the light enters the back of the lens and the detector probe is at the front of the lens you will get lower transmission than if the light is coming in through the front and the detector probe is located at the rear of the lens. This might make sense as the optics have changed, flipping a lens it becomes macro. 4. The focus of the lens matters. If the lens is set to infinity or to its most macro position will affect the transmission of light. This doesn't just seem additive based on increasing the tube length of the lens as you focus closer. So for these plots you can ignore the maximum transmission number. I am not sure I have controlled everything properly. Just wanted to share the cut off points for these screen captures. For this set my 39mm custom lens was set as 100% transmission. Which is a single element fused silica lens. The "exposure time" was 1000 ms for all lenses with average of 3 scans and boxcar setting of 3. This detector has a range of 178nm to 876nm, using grating #2, an L2 lens on the sensor and slit 25um. I am using a deuterium/halogen UV visible light source. All lens were measured with light entering the front of the lens and detector located behind the lens and with the lens set at infinity focus position. Ignore the settings in the screen grabs. I see i have them on the second module which was not used for transmission measurements. It just allowed me to collect raw data at the same time for each lens in the IR portion of the spectrum. It has grating #4 and appears to be exactly 3 times less sensitive to my other module at the overlapping wavelengths. Thus why its set to 3000 ms. Pentax 85mm UAT lens: KSS 60mm Macro f3.5 lens: Nikkor 80mm F5.6 EL lens: iGoriginal 35mm f3.5 lens: My 39mm lens with my SvBony #D 0.5x focal reducer: Sigma 30mm f2.8 Micro four thirds AF lens: Canon 40mm f2.8 STM lens: Canon 40mm f2.8 STM lens on the Metabones Speed booster ultra:

Does anyone have data on the transmission of IR for the Nikon EL 80mm (old metal version) beyound 700nm? I'd like to do some multispectral imaging with this lens but can't really find any spectral data beyound 700nm. I assume that it doesn't just cut sharply at 700nm :-).

Hi: I have a full-spectrum modified pentax K01 camera. I tried to take some UV flower pictures with two cheap Chinese UV pass + IR stacking filters and a SMC pentax DFA100 macro lens. I was be able to capture few "UV" (maybe not real UV) pictures with filters+lens but it was difficult because my SMC pentax 100mm lens is not an UV-capable lens. I wanted to buy an UV filter from the Ebay seller: UVIRoptic. He recommended to buy an UV capable lens first before invest money on an UV pass filter. I've checked all the pentax UV capable lenses listed here, and I am not sure which one I should get. So have anyone tested "early Asahi Opt. Macro-takumar 50mm F4 lens" for UV photography? Thank you. An example of the "UV" flower picture that I took, Roundleaf Ragwort (Packera obovata) ISO 200, f5.6, Bulb exposure 10 s. (sorry I don't know how to post a picture here). https://photos.app.goo.gl/2jrGd25T5G7PDV7q9

I showed an ad hoc image with shot with my Fused Silica 150mm Ø50mm plano-convex lens from Oriel in Jonathan's topic about his 40mm lens. https://www.ultravio...dpost__p__33743 The focus setting then was similar to the last refocussed one in the sequence below. Now I have made some tests with different apertures from f/8 and up. Without any limiting aperture the lens is ca f/2.3 and show massive spherical aberration making it very soft and hazy. For the second test I used an U-360, 2mm + S8612, 2mm stack. It is interesting to see how much focus shift and sharpness improvement I got at fully open (lacking) aperture.

It was suggested to me by nfoto that the AF-Nikkor 80mm/2.8 was a good sharp lens with adequate UV bandpass, and so it seems...this copy was recommended to me by nfoto herself, and I'm happy with it, so many thanks. F/5.6 1/4" ISO1600 1.75mm S8612 + 2mm UG11 In-camera white balance off the road, and saturation/contrast increased.