Debayering a DSLR's Bayer matrix.

[Gina]

hi, when I use a white screen on my laptop as the cwb for my debayered 350d, the jpgs are in greyscale, so should be the same.

but any idea why the outer area is devoid of colour? wouldn't it be normal colours, sans IR filter?

I see. The outer area is not completely devoid of colour just a bit lacking due to the lack of red killing filter. Hence the greens aren't very green. The blue in the sky (when we have any) shows as a rather magenta shade of blue. Outside the debayered area is an area where the micro lenses have been removed hence being a bit darker than out at the edges.

Here's another photo taken through an open window to the east.

Edited September 9, 2013 by Gina

[JamesF]

Try moving it slowly along. Your air may not be hot enough - mine burns paper.

451 degrees Fahrenheit

James

[Gina]

Here's a photo of the sensor and filter frame.

Edited September 9, 2013 by Gina

[alistairsam]

im a bit wary of increasing the heat too much. not sure if that can desolder the gold wires on the inside

[Gina]

I think you'll find the gold wires are welded on. At least that's how it was nearly half a century ago

[Gina]

More CFA removal and still OK I used some cotton cloth folded several times over the end of the plastic tool. Unlike the cloth that was on the original cleaning swab, this doesn't shed fibres. It's also thinner so provides a finer edge. Here is an image captured with EOS Utility and processed in Ps to return the colour balance to "normal" around the edge. The debayered area still looks red but less so. I think the monochrome area looks a bit magenta because the colour area has twice as much green as red or blue.

Edited September 9, 2013 by Gina

[alistairsam]

hi

I got the fringing on the glass but it needed a lot more heat.

320c, medium speed and atleast 20 secs on a spot.

[Gina]

As I think I mentioned, even when I'd gone all round the bond with heat and it was all fringing, it was still stuck firm and needed considereble force to get the glass off. So it would seem that heat is not all that's needed. I'll let you know how I get one with the next 1100D sensor

[Gina]

I've been reading up on DCRaw. I've put dcraw.exe in the Windows directory and a batch file in C:\Users\user\AppData\Roaming\Microsoft\Windows\SendTo containing the following code :-

@echo off
:begin
if _%1_==__ goto end
echo Processing %1...
c:\windows\dcraw -D -4 -T %1
shift
goto begin
:end

Could someone please confirm that this will convert the .CR2 file into a mono 16 bit linear TIFF? Or tell me what else I need?

Thanks

A bit later... Tried it and get this error message in Win 7 64bit :-

Edited September 9, 2013 by Gina

[Gina]

Found the problem - just what it said on the tin um.. error message - using the 32 bit version instaed of the 64 bit version. It seems to be working Converted CR2 file to TIFF, stretched it in Ps and here's the result - whole frame resized and cropped to debayered area and resized. With so much glass removed the kit lens will no longer focus on infinity so these are slightly out of focus.

[Ags]

Your command-line options look good to me

Edited September 9, 2013 by Ags

[badgerchap]

Starting to look pretty snazzy there Gina, excellent work. If you manage to get all the way with this, would you be kind enough to condense your efforts into a shorter thread, like you did with your excellent cooling work? Not that I'm lazy or owt but this un is a bit beefy now!

Typed inexpertly from my phone

[alistairsam]

I managed to get the fringing when heated on my practice 600d sensor and as Gina mentioned, the glass was still stubbornly stuck. but with some pressure, it popped off in pieces.

after applying the heat, I checked the electronics on the underside and they were all pretty hot. so not too sure if it'll survive, but its all or bust. so going with the live one tonight.

i also tried dabbing a damp tissue on the glass after heating to squelch it like we do metal, rather than letting it cool on its own. didn't make much difference but atleast I'm removing the heat quicker.

As for the gap below the sensor and electronics, jtw mentioned the 600d has only 0.6mm so is more difficult to insert a cold finger.

but what if we desolder the chip from the pcb and add metal spacers? that would lift the sensor and give more than 2mm for a cold finger.

of course it'll need precision soldering of the pins but I think it can be done.

Alistair

[alistairsam]

other option is to straighten the pins a bit so the chip gets lifted. mmm needs another thread, but its a thought...

[Gina]

Your command-line options look good to me

Thank you Agnes Great to see you back

[Gina]

Starting to look pretty snazzy there Gina, excellent work. If you manage to get all the way with this, would you be kind enough to condense your efforts into a shorter thread, like you did with your excellent cooling work? Not that I'm lazy or owt but this un is a bit beefy now!

Typed inexpertly from my phone

Thank you Yes, I'll do that. I do have a thread about debayering and cooling an 1100D already but I think I'll separate the two so as to produce shorter threads.

[Gina]

I wondered about lifting the actual sensor chip off the board a bit but even I am not going there Anyway, the cameras I presently have are alright in that respect and I'm not proposing to increase the number of models in my collection. I currently have 300D, 350D, 1000D and 1100D - that's quite enough, thank you very much Remains to be seen how far I go with the earlier models.

Edited September 10, 2013 by Gina

[Gina]

Here's the latest flat - CR2 to TIFF in dcraw then well stretched in Ps to show unevenness of the sensitivity. No sure if this is all due to eneven polishing or partly due to some residue.

[Gina]

Faulty 1100D arrived in the post this morning so another sensor to play with when I'm ready

[themos]

I've told my 450D to behave or else it will get sent to Gina!

[JamesF]

I've told my 450D to behave or else it will get sent to Gina!

I'd have thought you'd want it calm, relaxed and co-operative, not quaking in its boots

James

Edited September 10, 2013 by JamesF

[Gina]

More CFA removal and I think I might stop now while I'm still winning Here is the latest flat, stretched in Ps till it squeaked I did my best to clean it up using IPA on a cotton bud then dried using the other end so the darker area in the middle is where I've gone a bit too deep with the polish. It would appear to be still useable if corrected with flats.

Edited September 10, 2013 by Gina

[Gina]

More photos - mono image and colour photo much stretched to show sensor surface.

[themos]

I've had an entertaining few minutes explaining to colleagues why the image above left represented an "improvement" over a nice colour image.

[Gina]

Here is what it's all about. At the bottom of the image the CFA is more or less intact and you can see the quads of pixels and the fact that some of them are quite dark. The top part has had the CFA removed and all the pixels contribute to the brightness, in fact showing more sensitivity than any in the region below. This would be even more apparent if the view were a red colour rather than greenish as only one in four of the pixels with CFA would be responding to the red. This demonstrates that not only does this make the sensor more sensitive but the resolution is also improved. This is a close up view of part of the image above right.