Debayering a DSLR's Bayer matrix.

[Gina]

hi Gina

instead of three cameras and changing cameras, why not use a filter wheel?

so much easier and you only need one camera, no issues with the frame getting rotated when you change.

I have the sx usb wheel and 36mm unmounted filters and they're great.

cheers.

Alistair

I won't be changing cameras - the idea is to use three cameras with three lenses all at the same time.  I had started making up a camera with combined filter wheel but have decided not to waste photons by catching all three lots at the same time.  A filter wheel only lets one colour through at a time.  Same as OSC cameras only collect one colour photons on each pixel.

Edited November 28, 2013 by Gina

[Davey-T]

This is not an easy job - I have quite a large graveyard of sensors I have managed to destroy

Did you save them ? if so could you try some of your selection of acids to see if they dissolve the matrix without scraping.

Dave

[Gina]

Did you save them ? if so could you try some of your selection of acids to see if they dissolve the matrix without scraping.

Dave

Yes, I've still got them but most have already had the CFA removed.

[pixueto]

Not sure Gina, it was given to me by a friend who works with cameras, it did not matter too much to me since it was a test, the glass was a pain...need to work on that but the bayer must be very similar.

i will try it next without the glue because the tool i used really works very well.

and no matter how (reasonably) hard i press i cannot damage the gold coloured layer.

Are you going to try again?

Ray

Try with a 1000D. The glass is pretty easy yo remove and they are sold second hand at a good price.

[libraryman]

Hi, since i retired, i don't have the income to grab different cameras, i just use my 450D and my550D, if i can get hold of another sensor, i will make one last attempt and confirm that i can remove the bayer without damaging the sensor then use my own camera!!!

It seems that  the main issues are 

1.Glass removal..though it can be achieved with care

2.sealing the sensor with an inert gas to prevent moisture once the cover glass is replaced...not sure about this yet!

Ray 

[Gina]

Glass removal varies enormously from one model to another 350D, 450D, 1000D not too much of a problem but 1100D very near impossible.

I'm not using inert gas - just plain old air but in a sealed enclosure with silica gel to remove the moisture.  If the seal is good this will allow cooling to -20C without condensation though there would appear to be dinimishing returns below -10C.   I don't know why but maybe it's not thermal noise that's the whole problem.

[libraryman]

Yes i would agree with the diminishing returns point. i do not always cool my camera especially on frosty nights!

However; without your tenacity and the trials and tribulations of others attempting this mod, i would not be able to even contemplate it.

Is it fair then to ask!

Can the debayering mod with all it's risk and difficulty be termed "worth it" if one successfully completes without stuffing the sensor? 

And just one other query; the blue border..around the sensor..is that absolutely not to be broken into? 

Ray

[Gina]

Yes i would agree with the diminishing returns point. i do not always cool my camera especially on frosty nights!

However; without your tenacity and the trials and tribulations of others attempting this mod, i would not be able to even contemplate it.

Is it fair then to ask!

Can the debayering mod with all it's risk and difficulty be termed "worth it" if one successfully completes without stuffing the sensor? 

And just one other query; the blue border..around the sensor..is that absolutely not to be broken into? 

Ray

Thank you Ray   Ask whatever you like   Can't yet say whether it's worth it as I haven't properly tested it yet. 

I've taken off some of the blue border withouf killing it but I think some of it covers vital bits.  Best kept clear of.

[libraryman]

Thanks Gina, just off post for a sec...

hows the EQ8 going, have you managed to get some imaging in with it.

i found mine has a little Dec backlash but it's guiding well.

Back on post....yes that little border could well cover some vitals, i just wish that it was as easy as removing & changing the IR block filters. 

Ray

[Gina]

Thanks Gina, just off post for a sec...

hows the EQ8 going, have you managed to get some imaging in with it.

i found mine has a little Dec backlash but it's guiding well.

Back on post....yes that little border could well cover some vitals, i just wish that it was as easy as removing & changing the IR block filters. 

Ray

A rare event last night - clear skies!    Took me a while to get myself and kit sorted out after a long long time but eventually I got imaging going with the MN190.  One weight was just enough near the end of the bar to balance the MN190, two Evostar 80EDs and heavy ali plate connecting it all together.  At first I couldn't get a star image on the guide camera so tried unguided.  I need to get my PA better as I could only manage 20s unguided on stars low down in the east.  So I took some short subs on M42 for the centre part.  That was unbinned with the 460EX and a resolution of just over 2 arc secs per pixel.  Later I got the Lodestar sorted out and got guiding going though not very well - the sky had deteriorated by then and seeing/transparency reduced to 4-5 arc secs so I used binning 2x2.  After another go at M42 core with short exposures I tried for the surrounding luminous clouds with 5m subs for Ha and 10m for OIII and SII all using the MN190 (I haven't got the Evostars sorted out yet).  Not sure yet how many frames I got as it was getting late and I went to bed leaving it running.  I'm about to look at the data now.

Yes, debayering is pretty difficult that's for sure

Edited December 1, 2013 by Gina

[russellhq]

I really need to stop following this thread. After following it from the start, I've said to myself I won't do this to my camera. But now I've got the QHY8L and the 1100D is sitting in the corner gathering dust, temptation is getting the better of me! I've just ordered a 1000D sensor to practise on...

[libraryman]

Can you purchase spare 450D sensors?

Ray

[russellhq]

Can you purchase spare 450D sensors?

Ray

I've not seen many, but there's one one eBay at the moment. But it's in the US.

[Gina]

I've never seen 450D sensors on ebay.  I once saw another model - forget which now, It wasn't one I wanted.  Best way I've found is to buy non-working DSLRs.  These usually have working sensors especially if the problem is a stuck shuuter or something similar.

[StuartJPP]

I was browsing the web and came across this cross sectional scan of a Canon CMOS sensor (1D X). You may have already seen it (could be on one of the 71 pages of this thread), but it shows just how careful you have to be at removing the CFA...

Article:

http://www.chipworks.com/en/technical-competitive-analysis/resources/blog/full-frame-dslr-cameras-canon-stays-the-course/

[libraryman]

A very good illustration of the problem, i would assume that the matrix is removed up to but not including the Optical pad!! 

R

[alistairsam]

I won't be changing cameras - the idea is to use three cameras with three lenses all at the same time. I had started making up a camera with combined filter wheel but have decided not to waste photons by catching all three lots at the same time. A filter wheel only lets one colour through at a time. Same as OSC cameras only collect one colour photons on each pixel.

hi

not sure where you got to with this but if its lrgb then you could use just two.

one a mono for the details and the other a filter modded colour dslr for rgb. rgb doesn't

Alistair

[billhinge]

There is a new alternative - Phase 1 (high end medium format camera manufacturer) now offer a monochrome 645 format digital back at 60 mega pixels (2.5 size of full frame)

"The IQ260 Achromatic offers pure black and white images; no filters or interpolation applied. The 60 megapixel captures are stunning and pin sharp. As there is no IR cut-off filter mounted on the sensor, there are endless opportunities to create very distinct imagery both for artistic and scientific purposes using the wide array of lens-mounted filters on the market."

http://www.phaseone.com/Camera-Systems/IQ2-Series.aspx

price only 30000 - 50000 euro !

[Gina]

Oh is that all....

[JamesF]

For that much I'd at least want a few shades of grey as well as black and white.

James

[zvaragabor]

I was pondering whether to put the glass cover back on. Any bit of glass is going to lose you around 5%, and having no glass in the image train at all would be good for Venus images as you'd get more UV reaching the sensor. I suppose the shutter will be closed when the camera is off the telescope so the sensor will be fairly protected without the glass.

Not a DSLR I know, but here's some interim test results with an SPC900NC.

In between the original section and where the filter's been removed you can see a dark patch where just the top microlens layer has gone. You can see it decreases the sensitivity a fair bit, but this is then made up when removing the filter. The net result isn't a huge change in sensitivity in optical, but it'll be noticably improved for IR and UV imaging. However the improvement in resolution is pretty obvious even with my crude test-card setup.

Does the SPC900 still work? Could you please show some pics taken with it? How did you create the middle pic? Thanks!

Cheers,

Zvara

[Rottweiler]

Hi Everyone! I would like to post our latest attempt using glass polish rather than mechanical scraping (although the pencil tip attempt I read about looks also interesting). Also, if you have any parts left over from debayering attempts please send me a PM, spare parts are nice to have around!

[Rottweiler]

Apologies, there seems to be no edit button

That first photo is HDR. The edges are cropped by about 10 pixels, going for a 100% debayering seems to be no worth the risk for such a small sacrifice. No flat calibration, just normal processing as a regular photographer would do it.

Now some more normal images -

[russellhq]

Which camera model was this? Looks very good!

[Rottweiler]

This is an 1100D. Thanks