Noobulosity

I've seen DCM mentioned multiple times, but it sounds like that stuff is pretty bad for you. I tried DMSO because it's actually pretty safe, and even used as a topical pain reliever. I contacted the chemical company I found earlier to see if they have a recommendation. But, yes, it's possible that dissolving the coating could mean dissolving protective layers and even attacking the tiny electronics. Guess we'll see. That's why I'll practice on the damaged sensors.

Picked up some dimethyl sulfoxide (DMSO), based on the info I found. Applied it to the sensor and face it some time. Unfortunately, it doesn't seem to be working. But I'll let some of it sit and soak on the CFA for now and see if it gets any better. But right now it hasn't really softened at all. I think we can probably rule that one out.

Doing a Google search just for "photoresist remover" popped up an interesting hit on the first link; a PDF from Micro Chemicals GmbH describing different options for removing photoresist material. In the white paper, they mention NMP, as well as alternatives (because NMP is apparently quite toxic). Looking at another link to their site, I'm curious if the "Image Reversal" or "cross-linking" (positive or negative) lift-off options might be viable. Though, as Louise said, I don't know where you'd get small quantities of this stuff. Looks like typical sales volume is 6x 2.5L bottles or larger sizes. Maybe they'd be willing to ship samples for a small fee?

I appreciate that you want to get something back from investing in your time and efforts. But I already have a monochrome conversion on my Canon 7D now. I just want to clean up the CFA around the perimeter, if possible. Also, this thread was started with an aim at experimenting, trading ideas, and coming up with a way to do this ourselves. It's fun and interesting. I'm not interested in making any money on this, and I'm not looking to pay anyone to do it for me (or pay for the formula, or pay for sensors already converted). If you're not willing to share your chemical process, that's okay. But it seems you're more interested in getting business from this thread than contributing to it. You've mentioned multiple times now that you know how to accomplish CFA removal, but you haven't mentioned any of your methods. There are multiple places here in the US where I can send my camera to have it converted. The whole point here is doing it ourselves.

Got a chance to quickly process my images over lunch today. Here's a monochrome stack of the entire frame. I'm sure I could pull out more detail with some time, but I didn't have a lot of time to work on it, yet. Definitely seems like it's a lot more sensitive. I'm hoping to compare this with a quick stack of about the same integration time from my unmodified Canon 7DII.

Got a chance to mess with the camera again tonight. Looks like we'll have clouds for at least a few days, so I wanted to jump on the chance to test it while the night sky was clear. I don't have time to process the pics tonight. However, I was able to pin down the source of that weird illumination in my images. I was imaging with the rear screen on. It may be specific to live view, though I didn't test LV vs just having the info displayed. But, I turned off the screen and VOILA! The odd illumination was eliminated! I'll post pics after I get to processing them tomorrow. For now, I'm off to bed! Clear skies!

Thanks for the tips! I'd love to learn a bit more about the process you use to remove the CFA. Would you be willing to share what steps you take and which chemical(s) are involved? I can agree about the debris... that stuff is hard to clean off the sensor after scraping it up.

Tested the latest sensor last night. It's definitely noticeably more-sensitive to any light coming in. However, I noticed some odd bright streaking just left of center. I'm guessing it's because of how I removed the film from the sensor in that area. Maybe I can even it out. Or maybe it's because of micro scratches. No idea, yet. In the open area next to it, I was able to get decent data on M8, Lagoon Nebula in narrowband H-alpha. The example here is heavily-cropped to get just the nebula in the lower right of the full frame. 13x 2.5' light frames, ISO 200 (Yep, 200!) Included a few darks, a dozen flats taken against a solid red computer screen, and a couple dozen bias frames. Only editing done here is minor stretching, cropping, and converting to full B/W.

Huzzah! Replacement sensor has been debayered! It's not perfect, by any means. There's still a little debris around the edges and a few specks on the center portion, but it works. A few images... A close-up of one of the corners, you can see the depth of debayering isn't perfectly even, but I think flats will help smooth it out. (Click for large version.) Test Flat - Closeup Corner by Eric Schubert Test shot out the window. I'm not 100% sure on how DCRAW is doing its thing. A close look still shows a few pixels here and there in the field as magenta. But, we'll see how astro images turn out. That could just be sensor noise that will disappear with calibration frames.

Well, sensor #3 just showed up in the mail today. I'm still not 100% positive on trying this again, but I completely understand the feeling of determination in succeeding at this. I really want to try it again.

I got my second sensor, and messed that one up. I had a slip of the X-acto knife as I was gently prying up the cover glass. I didn't break any gold wires, but I did scratch the sensor surface. Probably a bit too deeply. Half the frame is black, the other half has wave after wave of wide, darker horizontal lines scrolling up through the picture. But, I am getting better at removing the Bayer matrix. The oak dowel sharpened up did work for roughly removing the layers. I added a touch of polishing material to help get the surface cleaner. The scratch was just too much, though... In any case, I ordered one more sensor. I may mess with the half-working one for now, just to see how it works out. But, I'm not sure I'll modify the 3rd sensor, yet. Maybe I'll give it one more go, but I may just skip it, install the stock sensor as-is, and save up a little more for a cooled CCD. Fun project, though.

I knew it was a very good possibility that I'd kill my sensor. While I'm a bit disappointed that I messed it up after it was actually working well, I can't be too mad about it. Them's the breaks, as they say.

Well... I must have hit something. I have a feeling that using cotton swabs is a bad idea, because the fibers can stick out to the sides and slip underneath the frame the filters used to utilize. I must have clipped one of those gold wires trying to clean things off, because now half of the sensor works fine, and the other half is darker and has lines to it. You still get picture on both halves, but only the one side is really usable anymore. I ordered another sensor from eBay for $65, so I'll give it one more shot and try to be a bit more diligent with my next attempt.

Finally made it through the massive amount of posts in this thread. Whew! What a loooooong journey! I actually joined just so I could post my own adventure. Unfortunately (fortunately?), I cannot claim my spot in the DSLR Killer Club. With so many successes sprinkled throughout the thread, and despite a heap of dead sensors from various attempts, I was inspired to try this myself. I have an astro-modified Canon T3i that I had considered testing this on. But, I was hesitant to use that camera. Instead, I found a cheaper Canon 7D to test this on. (Nearly $100 less than the T3i's typically go for right now.) I ended up having very little trouble removing the sensor cover glass with heat and gentle prying with an X-acto blade. When it popped off it nearly scared me, lol. But, I just made my way carefully, slowly heating up the frame until the adhesive turned white and loosened right up. A little extra lift from a thin blade and it popped right off. From there, the hard part was removing the micro-lenses and CFA layer. These were quite hard. I started with a simple toothpick, which had trouble making any headway at all. Then I tried adding some fine polishing compound to the toothpick, and that started doing something, but it mostly seemed to be only affecting the micro-lenses. The CFA wasn't doing anything. Then, after seeing the post regarding an aluminum rivet, I decided to give brass rod a try. I flattened the tip of it at an angle, and that had very little trouble making it through the CFA layer, but didn't seem to cause much trouble for the sensor beneath. I was very careful to stay away from the edges, so there's still a CFA border around the sensor. To get the last of the CFA off the center of the image, I used the toothpick again to polish off the little bits left over. Still need to do a little more clean-up, though. (See flat below.) I did end up with a tiny scratch or two, and one horizontal and one vertical line of dead pixels. Fortunately those dead lines are long the perimeter, so they can be easily cropped out of the image. Overall, I'm quite happy with how this turned out. Progress pics: Here you can see a bit of uneven scraping, but not horrible: My first monochrome image! Taken through my WO Zenithstar 103 at a distant power pole. I opened this in IRIS and it converted it automatically to monochrome, but wouldn't let me change the debayering to get rid of the pixelation. So, I went with DCRaw instead, and that did the trick. A flat taken against a white monitor, using my Sigma 18-35mm f/1.8 Art lens, settings were 35mm FL, f/1.8, ISO100, 1/250s Heavily-stretched. You can see the scratches. And it seems there are bits of leftover CFA on the sensor that need removing. I can't see them with my own eye, but they must be there. So, I'll have to clean things up a bit more. Might just do that right through the bayonet mount with the mirror up.