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Old 19-12-2016, 12:34 AM
flolic (Filip)
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Join Date: Jul 2016
Location: Split, Croatia
Posts: 48
Quote:
Originally Posted by luka View Post
Great work Filip

Few questions about debayering the sensor? I had a practice go at a broken one (from a broken camera) and while I debayered it I am not sure about the outcome as the sensor (and my DSLR) was already broken.

Did you just scrape the CFA or did you use something like dichloromethane (paintstripper) to soften the CFA?
I tried the dichloromethae method and it worked well but I had issues cleaning the gel-like leftovers. The sensor cleaned OK but the surroundings are covered by it and wiping is out of question because of the gold wires. I covered them by epoxy but some of the ends where it attaches to the sensor surface are still exposed as I did not want to risk getting epoxy on the sensor itself.

Also did you use epoxy to protect the gold wires and did you seal the sensor with the original glass again or did you just leave it open?

Thank you
Luka
Thanks Luka and others!
I soaked sensor surface with Ethyl acetate, that thing will not dissolve the Bayer mask and microlenses, but it will make them much softer. Than I precisely sharpened end of wooden handle of the small art brush and scraped surface under stereo microscope with it (if I remember correctly, under 20x magnification).
Ethyl acetate evaporate very fast, so I was constantly adding it and never let the surface to dry out. That is very important, because as you scrape the surface, small fragments of Bayer mask will migrate through all the liquid, but will not stuck on some other area of the sensor.
I was working slowly from the middle to the edges. Edges are particularly sensitive because there are some very sensitive circuitry right next to the active pixels region that you can (will) kill if you scrape it. Those areas are under blue area, but there are also some narrow strips between active pixels and blue area that you should avoid touching.
The safest bet is to leave some Bayer mask near the sensor edges, but I decided (and succeeded) to clean it to the very last pixel But you absolutely need steady hand, good microscope and adequately sharpened wooden tool for that.

After the whole surface was scraped off I rinsed it with Ethyl acetate and while it was still wet with isopropyl alcohol. Than I blow the alcohol off with compressed air and examined surface under microscope (with highest magnification). Any remaining speck was then cleaned off with sharpened toothpick.
You can then install the sensor in the camera and check is it still working and is it clean.


For me, the hardest part was to remove original cover glass without damaging the sensor. My glass shattered but did not damage surface or any of the bonding wires.
I did not covered the bonding wires in epoxy. Working under the microscope , they are far away and of no concern to me ( but I did cover them few years ago when I was debayering my 450D without microscope).
If you are using regular epoxy there is a risk that it will break wires because it shrinks a little while setting.

I glued new glass on my sensor using UV curable resin.

You will not blow off bonding wires using regular air compressor (cca. 6 bar pressure) At least that's my experience on dozen of different sensors...
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