artur5
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uhoh7 wrote:
You are skeptical about a .2mm IR cut? Who isn't? If it was a given we would see such ultra-thin filters already. Trying something new with the idea of improving performance, to the tune of getting a camera and installing the ultra thin filter and then sending it out for testing seems like a good deed to me.
Already dismissed by you. Nice. 
Not much hope, for what? Links to A7rii kolari v? vs stock A7rii would be nice to see with lens info. Results "same as A7s" meaning?
One thing you make clear: you are skeptical and don't have much hope  I feel just the opposite when I look at Sam's shots with the ZM 21/4.5, do you realize that is something totally different?
TY for that clarification, Sam. You make a critical point which will really help people choose how they might mod.
To for those who have not been following the thread in detail: we are talking about 3 different cameras, with three completely different mods, not including the cameras which Heip is talking about, which also come in three flavors. Hence my "v?". Each of the three Kolari mods have different IR glass, hence different WB issues. I found the v3 (no longer available) was the hardest to correct.
The three "new" mods:
Sam's camera has no coverglass + .7mm IR cut. I am not sure the exact spec on that glass, but it does have WB which is more difficult to deal with, as Sam says. I was working with his RAWs today. One of my questions was about how effective his IR cut was, but looking at various fabrics in his test shots, I think the IR seems OK. The color mix in general is tricky.
Sam's friend, Astroman, also had the Taiwan tech NK remove the coverglass and filterstack, but, as Sam says, replaces with .85mm STC (brand) IR cut, which appears to have excellent WB without any special profiles. It is designed to work with Sony AWB, if I'm not mistaken. I've seen RAWs from that camera and SEM 21, colors are good and edges seem good as my M9, but I would love to see it with a harder lens like the 21/4.5, or something similar. I suspect edge performance is similar, but would be nice to see. SEM 21 is very friendly lens, already good on Kolari v1 & 2, though if fully at M240 level like SEM 18, it's not clear.
Heip, do you understand these are the first two A7x cameras ever to have very close to Leica glass over sensor thickness? Sam's is slightly less, Astro very slightly more, if .8mm is correct for M9 & 240. The Kolari v2 thickness is 1.5mm. .7mm clear coverglass + .8mm IR, is my understanding.
The third camera, and object of Heip's lament, I presume, is Kolari's experiment with an ultra thin IR cut, a new glass type, as a way to avoid removing the base coverglass and have a simpler mod. It will have a total thickness around .9mm. .7mm clear coverglass + .2mm IR cut.
I'm very excited to try it, not because I think it's a slam-dunk, but because it's a new attempt. Kolari also is "skeptical". But I guess, Heip, I should just send the camera back, right? No need to see what it does, it can't work. So nice to have your encouragement
Once again I'll clarify myself in this highly controversial endeavor  I'm excited to try the ultra thin Kolari, because it is so out of the box, with unheard of IR cut thinness. NOT BECAUSE I'M PREDICTING IT WILL WORK! I never did. Kolari never has. This is something they want me to try, to see what happens. Excuse me for getting excited about the chance to experiment with another way. Excuse for me sharing the process, how stupid of me, when so many already know the answer. Jeez! My optimism for A7rii as a great M platform has nothing to do with that experiment, though I will be delighted if it defies all the people who make the obvious point that such a thin IR cut may not work. I am heavily rooting for the Kolari ultra thin underdog now, more than ever!!! To intensify the drama the camera was weather delayed and is still a few days out.
What makes me optimistic about the future is seeing the real results from Sam and Astroman's cameras. Sam has unprecedented edges with some very hard lenses, and Astro has good WB and only very slightly thicker IR glass. Their results strongly suggest there is no Leica sensor voodoo the Sony sensors can't match with the right coverglass and a profile. That is exciting to me.
Those mods use a special clean room technique where NK seals the sensor against the new IR cut once the cover glass is removed. That's not the only way it can be done. The .7mm clear coverglass can also be directly replaced and reglued with any specified IR cut and thickness. This done all the time by specialized techs with DSLRs. So far no one has done it with a A7x (that we know), but the proof of concept is already established: the hard part is getting the glass off. NK proves that can be done. The USA based specialist I talked with thought it would be no harder than the other FF sensors they already deal with. That route would be more expensive I'd guess, but how much is not clear. I'm positive it would be cheaper than a WATE, or the new 70200/2.8, or any number of single M or FE lenses, which many of us struggle to resist adding to our collection. A great mod would be worth the price of a lens to me 
In NK's method or a coverglass replacement (throwing out filter stack) the question is only: which IR cut? How thick?. We already know there is room to move the sensor forward to hit infinity. Will there soon be tens of thousands of modified A7rii shooting M glass just as well as Leica? Not likely, since it's as irrationally controversial as electric mountain bikes Then there is the totally rational issue that the modded camera will not shoot natives as well as a stock camera. If you do have natives you like, then you still have the option to use the external filters that Fred has helped develop. When you really do it right, like he does with the 35/1.4, the lens won't work on your M body (may not always be the case with other lenses, check the thread in the Sony forum). I just want to have two nice sibling bodies: RF M and EVF Sony which love the same lenses. Which to a great degree, with my lens set, I already do with A7.mod v1 and v2 (I did not like v3) The r2 ISO and hi-rez potential attract me, though, and for that camera I want the best mod possible. So much so I'm willing to test new choices, before I decide. 
You know what? I'm not the only one who would like a A7x as friendly to all the M lenses as a 240, or close as possible, anyway. Plenty of very curious people who love M lenses and want to know their choices. We are so lucky Sam is sharing what new ways are possible. Obviously others in his part of the world share our desire. Kolari is inspired to try a completely new approach to reach that goal. They have already done great by me, so I'll help them and root for success, why not? ...Show more →
Great post, yes sir ( albeit not very succinct .. )
Are you positive about the exact thickness of the glass sheet bonded to the sensor?. I expect that the Taiwan master should know, if he removed it. Did he say it’s 0.7mm. to Sam or maybe Kolari told you?
About the IR filters of Leica M cameras, I‘ve read somewhere, time ago, that they range from 0.5mm. for the M8, 0.7mm. for the M9 and 0.9mm for the M240. Your numbers differ slightly but I suppose that 0.1mm. more or less are of no significance.
My take on the front filter mod is that it never will be so effective as the internal cover mod. because it adds another sheet of glass in the light path to correct the ‘harm’ done by the thick sensor cover, while Kolari style mods remove unwanted thickness of glass and I guess that less is better.
On the other part, the FF mod has paramount advantages :
1- Cost - with some lenses you only need a couple of step-rings and a close-up lens costing 15-30$. Next to nothing compared to a Kolari mod.
2- No warranty voided.
3- Keeps perfect compatibility with native FE lenses.
All factors considered, I think that for people not owning a M camera the FF filter solution makes a lot of sense, specially if you want to keep costs down.
Anyway, even if you want to use your M glass on Leica bodies, the modification needed in most cases for the Front filter mod (basically reducing the flange distance by removing internal shims) it doesn’t jeopardizes their use with M cameras. If anything, the lens will focus a bit past infinity and the distance in the lens won’t correspond to the real distance, but the accuracy of the rangefinder isn’t changed, unless you remove rear shims. It’s a case per case affair. With some lenses, like the ZM35/1,4, no need to modify anything. You only want a M to Sony-E adapter that focuses a bit past infinity (either a cheapo model or one with adjustable infinity )
Another not very succinct post either, I’m afraid. 
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I also know that you love engaging in (unconstructive) internet arguments
