Debayering a DSLR's Bayer matrix.

[Gina]

The broken 1100D I bought off ebay came this afternoon.  Been bounced   Flash broken and stuck in the up position and lens very stiff but I'm not bothered about either of them.  Put a battery, SD card and working lens in/on it and checked that the sensor worked - it did   Just set it to Auto pointed it out of the window and pressed the shutter button.  So the sensor, main board and shutter all work, so that's a viable astro camera complete.  I'm happy for £80 all in

I'm now taking it apart and will cut out the wanted part of the top ribbon cable, recheck the required connections for ON and M and solder some bridges onto the switch contacts.  I'll then recheck that it works and post a photo.

I've also started debayering the 1100D sensor that I applied epoxy resin to.  Tried with just a dry buffing tool on the Bremel clone but it only took off the micro lenses.  Then applied a tiny amount of Scratch X 2.0 and got through to the gold layer.  Once broken through it was possible to remove CFA with a dry tool but it will be a very long job that way and I think I'll revert to the polish.

[Gina]

Taken some photos of the 1100D top ribbon ON/OFF and selector switch.  It requires more interconnections than the 450D.

With selector and ON/OFF contacts in place

Without contacts showing the power connection in red and the selector connections in black

Wiring for the selector

Finally, my attempt at soldering.  I could have done with a microscope, smaller soldering iron tip and fine insulated wire.

Edited May 16, 2014 by Gina

[Thalestris24]

Hi Gina

Something like this might be handy!

http://www.amazon.co.uk/Bresser-Microscope-5802000-Biolux-ICD/dp/B0017J7NW6/ref=sr_1_2?ie=UTF8&qid=1400262882&sr=8-2&keywords=binocular+microscope

Dunno how you manage without a microscope! Must be very hard to see detail!

Louise

[Gina]

Reading glasses and a good illuminated magnifier

[Thalestris24]

Reading glasses and a good illuminated magnifier

Hmm... a bino microscope would be much better, I'm sure!

[russellhq]

Taken some photos of the 1100D top ribbon ON/OFF and selector switch.  It requires more interconnections than the 450D.

With selector and ON/OFF contacts in place

Top Ribbon 01.jpg

Without contacts showing the power connection in red and the selector connections in black

Top Ribbon 02.jpg

Wiring for the selector

Top Ribbon 03.jpg

Finally, my attempt at soldering.  I could have done with a microscope, smaller soldering iron tip and fine insulated wire.

Top Ribbon 04.jpg

Looks good, although why didn't you take advantage of the common pads which were close by the selector pads?

I marked the common pads on your sketch with a green dot and marked proposed connections in red:

[Gina]

Because I wasn't sure what that inbetween contact connected to.

[russellhq]

Because I wasn't sure what that inbetween contact connected to.

I checked with my multiprobe and it seems to connect to the other ones marked green. Do you think it would cause a problem if you used it to bring the connections instead of using wire? I quite liked the idea of using conductive paint but I don't know enough about electronics to say either way.

[Gina]

I've just had a closeup look at the ribbon switch contacts and their "via" connections to the other side, the large area of which is the ground plane.  And yes that inbetween contact is indeed connected to ground, so solder bridges (or other connection method) would be fine as you say   Seems I wasted my time with the wire   Oh well... that's nothing unusual!

[russellhq]

I've just had a closeup look at the ribbon switch contacts and their "via" connections to the other side, the large area of which is the ground plane.  And yes that inbetween contact is indeed connected to ground, so solder bridges (or other connection method) would be fine as you say   Seems I wasted my time with the wire   Oh well... that's nothing unusual!

I think you just enjoy doing things the hard way!

[Gina]

I think you just enjoy doing things the hard way!

It would certainly seem like it, wouldn't it

[Gina]

I now have the 1100D sensor I've been working on ready for testing.  I've removed the CFA from a small area and micro lenses from a larger area.  The slope down from the area with CFA to the gold coloured area without shows narrow bands of green, red and blue.  I must see if I can find my USB microscope and take some microphotos.  Should've thought of that before but my mind has been overloaded with other things!

I am in a totally disorganised state here but hope and indeed, plan, to get things better organised.  Then I won't spend half the time spent on my many projects looking for things and geting thoroughly frustrated!  I'm certainly not short of things to do and keep myself busy

Edited May 17, 2014 by Gina

[Dave_D]

so many people with toys to play with... *stamps foot and sulks*

[Gina]

Report of test of 1100D sensor part debayered :- dead!   Just a black image, no error message.  Tested manually saving to SD card and with EOS Utility via USB.  Guess I must have gone too deep.  Next time I'll use manual CFA removal with cotton cloth over plastic tool and polish.  Slower but more controlable. 

Meanwhile, I'll have a go with a 1000D sensor (or maybe 450D one).  But not tonight - had enough for today!

Edited May 17, 2014 by Gina

[Gina]

Before trying again to attack an 1100D sensor I'm going to practice on 1000Ds

I now have a 1000D test setup (at room temperature so far) and have checked that the sensor assembly I bought from another member was working properly before commencing debayering.

Having confirmed that I'm now in the process of removing the cover glass by carefully working round the glue joint with an Exacto type knife.

[Gina]

Glass now off and sensor ready for epoxy resin   Close up check shows all gold wires intact - I turned the sensor upside down to finally remove the glass to stop it touching the wires.

[Gina]

First try with the 1mL syringes.  Better than the 2mL - bit more control but still not really good enough - still getting resin coming out in fits and starts.  I was trying (very hard) to push out just enough resin to fill the trough round the sensor itself but control just wasn't good enough and it ran over onto the imaging surface.

A 1mL syringe is sufficient for two sensors so I took the previously debayered sensor that didn't have epoxy on it and practiced on that with the second half of the syringe full.

Here are photos of the results.  Not what I would call good.

[Davey-T]

Hi Gina, I was waiting until a set system for debayering was established before attacking my 450d but now I'm feeling guilty that your'e left to do all the pioneering work, perhaps you could make some sort of fence to control the resin, maybe glue it to the sensor with a small amount of resin and fill in behind when it's hardened, then it could be left in place permanently, just an idea, maybe talking rubbish 

Dave

[Gina]

I don't mind being a pioneer   Quite the opposite   But there may not be too much progress here as I'm finding it difficult to concentrate on things ATM.  Also, with people coming in pretty often I'm having to keep the living room, which is also my workshop tidy enough for visitors.  So I'm tending to pile stuff into boxes and not label them.  I need to get myself better organised and until then the various camera parts and tools I need for the job have a habit of disappearing   In a week or two I may have all the current unpleasant stuff out of the way and may be able to concentrate more on my projects.

Fences around the sensor sound a reasonable idea until you realise that you are within a few thou of those fragile gold wires  

An automated setup for this job would be ideal and I need to do some serious thinking.  That is proving difficult at present.  It may be possible to use something like a 3D printer with a syringe replacing the extruder hot end though the expression "using a sledgehammer to crack a nut" comes to mind

Edited May 21, 2014 by Gina

[Davey-T]

Some precision automation sounds good but may take longer to tool up than do the job, ok if you're starting a production line I guess

A printed fence with locating lugs to keep it away from the wires maybe ?

Dave

[Gina]

I'm afraid 3D printers aren't that accurate - at least mine isn't.  I think it might work for dribbling resin onto the gold wires and the extruder motor could be arranged to push the syringe plunger while the print bed moves the sensor so that the right point is under the syringe nozzle.  But that is just one idea...

[Gina]

Here's a photo of the top ribon cable converted for astro use, fixed to ON and M, using solder blobs only,

[pixueto]

Dear all,

Sorry if I didn't post here lately but, after trying a few times this mod, I got a bit tired. I have quite a lot of experience at the moment with this extreme mod so let me summarise my findings.

1. First, all you have to do with the epoxy is to keep it at bay with a sensor swab (with microfiber) until it starts setting and stops flowing onto the sensor. This will happen in about 20-30 minutes. It doesn't matter if the sensor has some epoxy residue; you can clean it with isopropanol once the epoxy is fresh but not moving (or even not bother to clean it at all as it will easily go away once you star debayering the CFA). The epoxy part is not a critical step in this mod at all.

2. The golden connectors are delicate but not as delicate as most people here think. I can tell you that they have taken a lot of punishment from my methods and they still work. Yes, try to avoid touching them but, although delicate, they aren't as troublesome as everybody thinks here.

3. The part that REALLY is very delicate, is the coloured edges on the sides where there aren't golden connectors. This is a REALLY DELICATE area and if you remove the CFA a tiny bit from there, chances are that your sensor will be damaged. Thus, all the work should be put into protecting those coloured sides. The golden connectors are delicate but much, much less critical than that area.

4. There are two sensors who are easy to work with: these are  the canon 1000D and 450D. Also, the cover glass is very easy to remove in one piece in those without applying any heat.

5. I have managed to debayer the sensor in the 1000D with the dremel and felt tips until I nearly got to the circuitry and the sensor still works. I can tell you that this sensor is really robust. The problem I have encountered here is that I found it impossible to debayer the sensor in a completely uniform way, which has always been my goal.

6. With the sensor in the 450D, I can debayer it leaving a completely homogeneous finish without any gradients left in the anti-reflecting coating so, although this sensor seems nearly identical to that of the 1000D, this leads me to believe that their construction varies in some way). The problem is that I haven't managed to debayer a 450D sensor without damaging it. I think this sensor is intrinsically weaker than that of the 1000D but I might be wrong as in my 2-3 failures with this sensor, I managed to get to the coloured sides by mistake which I know they are very delicate. I am not going to sacrifice another 450D for a while so it would be interesting if someone can proof that. The idea is to try debayering uniformly a 450D sensor only in the central area with a dremel and felt tips. If you manage to debayer only the central area in an homogeneous fashion without damaging the sensor, then this mod is perfectly achievable.

7. If you are using the dremel, only the felt tips are adequate. Any other: silicone, rubber, etc will damage the sensor. Even the felt will damage the sensor in the 350D model as its construction is very different from the others.

As I said, I am not going to spend more time and effort on this for a while (or maybe not) but it would be nice if someone could check if the 450D sensor can take this method.

By the way, it helps applying masking tape on top of the epoxy even when this is completely dry as the dremel and felt can remove a chunk of epoxy (this is what happened with my last 450D that got debayered a bit on one of the coloured sides). Green frog tape applied on top the epoxy once it's dry will effectively protect your golden connectors and coloured sides from the dremel and felt tips.

Well, I hope that helps. A few pounds were spent reaching these conclusions so it would be nice if someone can put them to good use and contributes to the thread to find a method for those brave enough to try it in the astrophotography community. The thing that I like about the dremel and felt approach is that it leaves no CFA residue and it can potentially achieve perfect flat frames. Nobody has achieved this so far; not even those companies selling monochrome converted cameras.

Also, I wouldn't worry about any other model apart from the 450D and the 1000D. The 1100D seems a really difficult one to crack (and this mod is a tremendous challenge even with a 100D or 450D). Other models: 500D, 550D, 600D, etc I don't think they are worth trying as failure would be really expensive and the nature of their sensors makes the loss of the microlenses a real inconvenience. The 1000D, for instance, clearly has a gain in sensitivity with the monochrome mod even though the microlenses are lost. I doubt the same can be said about any other models  (except perhaps the 450D -but I didn't manage to debayer one without damaging it to test this).

Edited May 23, 2014 by pixueto

[Gina]

Thank you for all that   I'm currently working with 1000Ds for deBayering - I have three   One sensor has reached the stage of having epoxy resin added but not yet tested.  I'm hoping to get testing over the weekend as I should have some time available.  I also have a 450D with the intention of deBayering the sensor.  As for the 1100D, I agree, it is extremely difficult to deal with, but I do have a couple of scrap cameras with good sensors that I might get round to trying again. 

[pixueto]

Hi Gina, the epoxy (Maplin's one) won't do any harm. The 1000D sensor can take almost everything as long as you don't touch the coloured edges were there aren't any connectors. Problem is that I really want a perfectly uniform sensor and I couldn't achieve that. Once I removed the CFA, I even tried toluene, N-Methyl-2-pyrrolidone and other substances that after some research I've found they are used in the sensor industry but they won't touch the AR coating. I did have success with the 450D as the dremel and felt tips remove the CFA and part of the coating uniformly. Unfortunately, no 450D sensor was left undamaged after the procedure. The annoying thing is that in all my 450D sensors, I managed to touch the coloured sides so the doubt remains if this was indeed the cause of failure.  A good test would be to debayer with the demel only 50% of the sensor in the central area (and leave a perfectly uniform finish with no coating gradients). In this way, without risking getting any close to the edges, sensor failure will show that this method can't be applied in the 450D. However, if the sensor works fine after this, there you go, it can be done with a perfect finish. At the moment I don't reallyknow the answer to this and I won't try it until I can get another 450D sensor at a reasonable price. It would be nice if someone in this thread tries this and see if we can move things forward.