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Sensor Stack Conversion for A7 and A7r to help with RF WA

cam

Active member
Jon, thank you, that's really good to know!

I, too, travel a lot, and live half the time in humid climes, so corrosion is definitely an issue for me, sigh… But, yeah, an A7S like that is a dream :D
 

noimmunity

New member
Jon, thank you, that's really good to know!

I, too, travel a lot, and live half the time in humid climes, so corrosion is definitely an issue for me, sigh… But, yeah, an A7S like that is a dream :D
Then again, if I understand their terms correctly, Kolari promises free replacement and eventual upgrade to non-corrosive glass, with, crucially, a fast turnaround time, to boot!
 

uhoh7

New member
Cam, Kolari Vision can remove the AA filter at the same time they perform the filter conversion.
Jon
Hi Jon,

After reading your post I contacted Kolari and asked about the AA filter.

"it is removed during the thinner stack change, the AA filter is part of the thick stack that we exchange."

This was the answer :)
 

karlfoto

New member
Hi forum

I am considering this mod for a yet to be purchased a7ii.

Can i take it that these filter specs are true.

For an A7

1. A ~.5 mm thick clear glass that is epoxied to the sensor.
2. An UV/IR cut (absorptive)/ AA stack of ~1.1mm. This is a 2 component epoxied "stack".
3. An UV/IR cut (dichroic)/dust shaker of .9mm thickness.

Total thickness = ~2.5mm.

Which ones are actually removed and not put back, which ones are removed and modified with a thinner filter?

A question for uhoh7. I saw your image of the umodded a7 with the sem 21. Have you had the mod done, and have you retested to see the improvement?

Thanx
Karl
 
V

Vivek

Guest
You are copying what I posted without acknowledging me and asking in general if that is true? :wtf:
 

karlfoto

New member
Hi Vivak

There was no malice intended. Sorry if i offended you.

So what is the origin of the specs, I may as well get it straight from the horses mouth.

Thanx
Karl
 
V

Vivek

Guest
It is me. I measured it. AFAIK, none the the guys being quoted have given the actual measurements.
 

Audii-Dudii

Active member
My Kolari Vision modified A7R arrived last Friday and today I finally had a chance to use it.

I use mine only with adapted lenses (primarily a Contax N 17-35/f2.8 zoom via Kipon's electronic adapter) and for your amusement, I present here two 100% crops from before-and-after photos I took just outside my front door. The two compositions are as identical as I could make them and the lens was set to 17mm (which had been the most problematic focal length) and stopped down to f8.

Here is a 600x600 crop of the lower left corner, taken with the unmodified camera with the OEM cover glass over the sensor:



And here is a 600x600 crop of the lower left corner, taken of the same scene, but with Kolari Vision's thin-filter installed:



Yes, the colors are different, because the two photos were taken under different light conditions and several months apart, but based upon this very limited test (which is nonetheless more than sufficient for my purposes, as I use this lens for ~85% of what I photograph), I will posit that this modification delivers far more than $400 worth of IQ improvement! The corners still aren't perfect, by any means, but they are now adequate whereas before they were not. :)

JG

P.S.: I've noticed no difference in IQ in the center of the photos, although many are claiming there is potentially some degradation when using Sony FE-mount lenses, as they were designed around the thickness of the original cover glass. YMMV.
 
Hi JG,

Thank you for sharing. It's interesting that even an SLR UWA would see such substantial improvement. If you have a FredMiranda account, would you post this finding there as well? Here is the link to the thread:

A thinner sensor stack may be possible after all! - FM Forums

I have tested the ZM 15, Elmar 24, Biogon g 21, 28, 45, 90, Contax 55 and 85 Jahre. All have seen noticeable improvement. The wider the better, but retrofocus lenses yield better end results.
 

Audii-Dudii

Active member
DJ,

Does IQ involve color moire and or CA?
Vivek:

I don't see a "DJ" in this thread, so I'm not sure if you're referring to my post above or not.

But if you are, then in my case, the answer is No.

This is because I convert nearly all of my photos to B&W and to my eyes, B&W moire is much less obnoxious than color moire, and I photograph almost exclusively at night, so the edges of my photos are usually hidden in shadows, eliminating most issues I would otherwise have with CA. Besides, I've found Capture One does a pretty good of eliminating it when I process the RAW files, so it's only ever a problem for me on very rare occasions.
 
V

Vivek

Guest
JG, Thanks for the info. :)

I also have no idea where DJ came from. :( Not what I intended to type.
 

uhoh7

New member
DJ,

Does IQ involve color moire and or CA?
Hi Vivek,

One lens which has dramatically improved for me, both for general IQ and especially CA is the Canon nFD 24/2

This lens produced basically terrible CA issues even stopped down on the stock A7r and A7. Now, however, it is a great lens.

Bridge in to Blue by unoh7, on Flickr

I have yet to spot moire in any still photo with the mod, but your eye may be better for that than mine.
 
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