Gina

The cover glass on the 450D comes off easily with an Exacto knife or similar - no heat required

Images from sensor - flat and view through living room window.

Put some insulation tape over the sensor and on the glass. Tried the hot knife - no joy, just turned the glue black where I had gouged out bits that showed white! Then attacked it with an Exacto knife. Another couple of bits of glass broke off - absolutely no sign of it shifting over most of that edge There is now a strip of glass remaining along that edge and the sensor is now clear. In spite of all the precautions, there is some damage to the sensor surface. I think the chances of getting the last of the glass off is negligible Next I put the filters back onto the sensor unit (to avoid any more damage), put it back into the camera and reassembled the camera for testing. The good news - the sensor still works. The bad news - two bright magenta horizontal lines and one black vertical line The glass also pulled the sticky tape down onto the middle of the sensor leaving a sticky patch but I imagine I shall be able to get that off with IPA. I'm not going to try any more to remove the rest of the glass. If I don't succeed in totally destroying the sensor in debayering I shall have to build up the frame to the level of the remaining cover glass before putting one of my spare cover glasses on to seal it. The remaining glass is clear of the imaging area. I'll take and post some pics shortly

I'm not going to risk the gas flame on it any more. May try hot knife-edge. I had the torch on it's lowest setting. I guess I must have applied too much heat trying to get that last bit of glue to turn white That was when the glass cracked and flew off.

Ah, I see

I have a blade in the Dremel blowtorch kit so I guess I could try that

They've brought their prices down since I last looked I agree that's not a bad price

I wonder if they have a number of failures and that's why they charge a lot for the finished camera and take a long time

Thank you Louise Yes, that's the method I've been using, pretty much. Glad you're debayering is done

OK - yer tis In case of confusion with my earlier postes, the RHS of this photo was at the top when I was heating the cover glass.

Might be an idea to put some adhesive tape over the exposed sensor and wires and also on the remaining glass so that it doesn't drop onto the wires or sensor. I'm giving it a rest for a bit while I gather my thoughts. And allow time for any suggestions anyone might have

Thanks Russel I think the last bit is going to be difficult - and that's an understatement!! The top seems to be very securely glued on. I started carefully lifting where there was some white but with another ping, a small bit flew off! Fortunately, well clearing the sensor - I think it landed on the floor. We are now up to a totally glued area. At the other end the glue has gone and the glass to frame area is showing moire fringes. If I apply too much pressure the corner will fly off I don't think heat is an option - I've already applied a lot of heat to that area and I don't know how to apply more heat without risking cooking the sensor or gold wires. TBH I don't know what to do next. I knew the glue wanted loosening all the way round and after the rest went I concentrated on the top bit but still very carefully as in your video. In spite of cooling the frame was hot - probably 70-80C going by touch.

Another day - another attack on a sensor I decided NOT to use the cold finger but to cool the frame and metal shield - only slightly. I used Russel's method and almost immediately I got white showing at the bottom. I continued carefully flicking the flame over the glass and the whiteness spread all across the bottom and up the sides but the top just would not turn white. After a couple of minutes of careful heating there was a "ping" and two thirds of the glass from the bottom flew off. I stopped at that stage and tried to prise off the rest of the glass without success. So being aware that the part of the sensor and gold wires were now exposed, I put the filter frame back and put the sensor back in the camera for testing. It still works

No, I think the heat just destroys the epoxy.

That looks well baked - nice and brown

Thank you Russel I think I'll have another go but with a lot less cooling. I thought the thermal gradient would help with the glass removal but it didn't - I think it may have caused the glass to crack. Last time I tried this I just had the cold finger attached to a large heat sink - no active cooling. Did the sensor work after you "cooked" it?

Thank you Louise I've checked all the settings. Now with the same camera and ribbon cable, just swapping sensor assemblies, the untouched one is working fine with EOS Utility but the one I removed the cover glass from is giving Err 70 and a black/blank image. I have yet to comfirm this with the other camera. Edit... Same now confirmed for the other camera - untouched sensor works - glass-less one doesn't. I conclude that I have proved beyon all reasonable doubt that the sensor sans glass is dud That is as far as I am going today. I now have two cameras with untouched working sensors that I have available for AP (in addition to the one I use for general photography). If I want to keep one for OSC that leaves just one for debayering. The "Last Chance Saloon" beckons

I took the cold finger out and swapped the ribbon cable for the one out of the working camera, checked all the ribon connections and it still gives "Err 70" after displaying a black image. So I think I have to assume the sensor is faulty. I've had another close inspection of the sensor and gold wires and it certainly looks like all the gold wires are intact with no sign of disconnection of any of them but there are a couple of scratches on the surface of the sensor that show as little gold lines. I wouldn't have thought that little bits of glass touching the sensor would go very deep but who knows - a candidate for sensor destruction I guess I can't see that it was the heat that did it in view of the cooling - there was ice on the cold finger. My only though is - could it be too much thermal gradient?

Thank you Louise Yes, you're right, that error can also be due to a bad connection or broken ribbon cable etc. so I'll carry on checking.

EOS Utility works fine with the working camera. But the one with the cover glass-less sensor takes an exposure, displays a black picture and says Err 70 (which means sensor fault). So it seems I've succeeded in destroying yet another sensor I guess one of those dreaded gold wires must have suffered even though they look fine. I don't think the sensor got overheated with all that cooling and ice on the cold finger.

Tried with a known-to-work camera and getting the same problem with APT So this seems to indicate it's not the sensor in the other camera. Possible culprits :- APT settings (not been altered), laptop, USB cable, "the nut behind the wheel" (me).

I have the camera back together but without the cooling as there's no point in testing with cooling unless the sensor works without it ATM I'm having a problem with the camera. I can't get it to work properly with APT - takes an exposure sometimes but then says "Busy" and won't do anything I've checked the ribbon cable connections and they seem alright. I'll do some more checking - I can't blame the sensor quite yet.

Thank you The 1100D has the most difficult cover glass to remove of all the Canon DSLRs I reckon I have worked on 300D, 350D, 450D, 1000D and 1100D, and the 1100D is the worst by far. With some such as the 450D, the cover glass comes off without heating quite easily.

Well the cover glass is all off now - in lots of bits Close inspection shows that all the gold wires are intact I have now replaced the filter frame complete with filters to protect the sensor and gold wires while I reassemble the test rig and see if the sensor still works. The cooling caused some condensation on the sensor so the image won't be perfect but the water marks will clean off after I've applied the epoxy resin - I'm not going anywhere near those fragile gold wires! PHEW!!! That was hairy

Cover glass removal in progress Procedure on hold ATM due to district nurse tending to Tim. Glass has cracked but the glue has turned white so I expect it will come off. I'll tip it up more though to avoid any pieces of glass touching the gold wires. Not bothered about cracked glass as I already have two spare ones. Fortunately they're all the same across the Canon models I have