uhoh7
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mcbroomf wrote:
It looks like purple flare to me (the book)
To test for IR contamination use a grey card in both shots, WB both, then use a colour picker to look at the colour levels in the black material. You must use a grey card and do a WB though, otherwise you can't compare. As far as I recall black fleece and black polyester are both good.
Mike
The top shot is M9. Just a quick shot against the light, but there were some blacks. I was looking to see if it was obviously leaking. I would not take any meaning from them. Minor editing. Or this:
Dark Road by unoh7, CV 21/4 A7.utv1 F/8
This is a misleading "A7 with M/LTM" shot, as the edges are near. Nevertheless, this lens is not great on M9 either. Without profile it has huge color shift and vignette on M9:
With and without profile on M9
One set is labeled F8 the other two are WO.
Nico uses F11 (M10 is better), and quite few of his shots are cropped. He tried 4 lenses to get his copy, but I have seen him do well with it. It was sundown in "Dark Road" so there was some red light, but not like that  . If you are expecting accurate WB, come back in 10 days or later. This is the very beginning of a three week testing process. I think some will like to see early samples as I see them and start working on WB and just shooting it a bit. If you don't like that, viewing is not compulsory. 
Rain all day today. More weather coming. The WB of the utv1 is very different than v2, however it responds across the spectrum. It will take me quite a while to see if I can get a handle on WB and possibly get a decent profile, however, that's not something I ever did well
I have a very heavy schedule in the next 10 days, so it may be several weeks before I can get a respectable set of infinity shots with all three cameras in good conditions. The last winter like this was 1861. 
Meanwhile I will post some samples just to give you an idea of what I'm starting from:
WB004-4 by unoh7, CV 35/1.2 A7.utv1
I am not pretending to present anything here except some very early snaps. Make of them what you will. Probably we will not know the full potential of this mod until the camera has been in few hands anyway.
WB004-11 by unoh7,CV 50/1.1 WO
another WB
DSC00142-4 by unoh7, on Flickr
PM me if you want a RAW of any of my samples here or on flickr. On the camera, changes in saturation effect the tonality alot. This is plain A7, it's the worst type of Sony RAW. But if somebody wants to attempt a camera profile for the thinnest IR cut ever on a FF Sony, maybe any FF, I will send you files, and try it out. I'm using LR latest.
My goal is to get some reasonable infinity shots, and test IR, so we can see if performance warrants the harder work of getting the right colors. It's Presidents's Week, one of my two busiest periods of the year, so please be patient.
Frankly, I expected more problems with blacks than I see so far. But that is only a part:
"OK, there's been a lot of talk about the effects infrared sensitivity can have on a digital camera. Some of it understates the problem (it only affects synthetic black fabrics) some overstates the problem (it causes "streaking").
So, here's a pretty complete list of the effects on infrared "contamination" on a visible light picture. I've seen most of these effects in the field with infrared sensitive cameras such as Nikon D100 (prompting me to invest in IR blocking filters).
1) Color accuracy issues: Blacks (not just synthetic) can go magenta or brown. You can see this in black human hair, animal fur (live or in clothing). Green vegetation and clothing can desaturate, or go yellow. Dark greens can go brown or magenta. Reds desaturate and can acquire "hot pink" casts.
2) Skin issues: Skin is more transparent to infrared than to visible light. Infrared penetrates several dermal layers before reflecting back, so you see the infrared "shadow" of sub surface blood (which absorbs much more infrared than skin). Veins become more visible, dark shadows under eyes are exaggerated. Any area where capillaries dilate shows as darker, where they constrict shows as a lighter, so skin can acquire a blotchy look.
3) X-Ray vision: In addition to human skin, many other substances are more transparent to infrared than visible light. There is an increased tendency to see underwear through clothing, grafitte that has been painted over, blemishes that you thought were covered by makeup.
4) Flare issues: Anti-reflective coatings on lenses are optimized for visible light and become less effective at infrared wavelengths. So you see an increase in flare, ghosting, a loss of contrast, and a particularly annoying artifact known as a "center spot". This effect is worse with complex lenses such as zooms having up to two dozen elements, and less of a problem with simple lenses having 4-8 elements. People on the Leica Camera User Forum have already reported this paradoxical behavior: although one expects adding any filter to increase flare and ghosting, you actually have less flare and ghosts when you add an IR blocking filter to an M8.
5) Sharpness issues: Lenses are only color corrected across the visible spectrum. This is why you need to compensate your focus for infrared photography. Since infrared contamination is causing the image to be a composite of both infrared and visible light, both the visible and IR can't be in sharp focus at the same time. You lose resolution, or "micro contrast"."
Joseph S Wisniewski
https://www.dpreview.com/forums/post/20838611
What jumps at me right away is "Reds desaturate and can acquire "hot pink" casts." That could be the case. Also the part about flare seems to apply to both the mod and the M9
Any here is OOC with something red:
DSC00129-4 by unoh7, Cropped 50/1.1 OOC but after in-camera adjustment. I will get some at base AWB.
Not the wall above the couch. I am seeing a pink cast there, no? Well one thing the M9 does over the top is red. So that will be a good comparison. So now we have a good list, please don't hesitate to mention any of those issues in samples going forward. UPDATE Multiple reds at my place actually seem fine in more recent shots. So we'll see.
Obviously there has been alot of skepticism about if a such a thin IR cut is possible. I was very surprised when Illija told me how thin this was, and having heard many opinions in other places, I was, and still am wondering if it can work.
This is interesting context :
theSuede wrote:
The Leica IR filter is a thinner version (0.5mm) of the standard plate of the cheapest possible material, the Kyocera BS7. Other manufacturers choose a more expensive plate material that's half the thickness (0.28mm is standard) and still gives better cut-off steepness, better partial refraction index and lower reflection index than the 0.5mm Leica - even in the base models. Here you have half the angle-dependent problem. So when Leica say "we chose a thinner plate" they're really feeding you a lot of BS, true only in the sense that they could have chosen a broken beerbottle in stead.
The angle-dependent efficiency of the sensor is clearly stated in the (now withdrawn and "classified", probably by Leica request) Kodak spec-sheet for the sensor - and it's "not good" to "really bad" depending on how you compare it to modern constructions. Loss at 25º incidence (with compensating microlenses) is more than twice that of comparable Canon/Sony/Nikon sensors - mostly due to the depth of the cell structure and the low fill-factor. In fact it's a lot worse than the 16x smaller cell compact-camera 1.65micron SONY BSI sensor......Show more →
From 2010. I've pmed him and others to try to learn what glass this is. So maybe something under .5mm is not so wild. At DPR I heard the exact same contention from Joseph S Wisniewsk.
BTW Optical thickness, or more accurately "Optical Depth" is a dimensionless number which is the product of Refractive index times thickness where 1mm = 1, if I have that right. There is not as much variation as you might think in the coverglass and IR cuts which concern us, however over time we can get many of those numbers. S8612 is around 1.5. I will guess the clear coverglass is closer to 1.4, but we will figure that out.
Also as suede notes the M8 .5mm IR cut/coverglass (only Leica combines these) is Kyocera BS7. Somebody had told me that was also S8612, but not so- BS7 was widely known, so I should have caught that, but since M8s don't seem to corrode, that makes sense If anyone can find the refractive index of BS7 please post it. I need to ask Sam about the figures for his .7mm and Astroman's .85mm STC.
Somebody ask Sony for the RI of their 1.9mm over the coverglass..... Well at least we can make an educated guess as what it could be at the minimum. I predict if anything the physical differences in thickness understate the advantage of the thinner glass over the sensor, which concerns us, in terms of optical depth.
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. Thank you!
). I have loved it ever since (OK v3 I returned for v2). I have seen enough to know Sam and Astro, with NK have taken the full step. The rest is software. That is serious history. The camera at my house right now, succeed or fail, it's trying something never done. Shoot me, I love that. That front filter work and Fred's ZM 35 modding...real history 
