spokeshave

I can't speak for the 1100D, but I found that looking for broken bodies is much more fruitful than trying to find the actual sensors. I recently bought a set of 5 broken 55D cameras off of eBay for less than $200. All had intact, working sensors. In fact, I was able to reconstruct 3 working cameras from the lot. Tim

Here's a link to a flat RAW file: https://drive.google.com/file/d/0B1MOziksBQm2OTQ5d0NsOU83Rjg/view?usp=sharing I stretched the flat heavily after decoding with the dcraw string above. Here's a jpeg. There are a few artifacts near the edges and corners indicating that I could do more polishing, but they won't affect imaging if I get decent flats. Still, I will continue to experiment to strive for perfection. I'm very encouraged by the results so far. Tim

Here is a link to the CR2 file: https://drive.google.com/file/d/0B1MOziksBQm2XzRubGxaMVAtR3c/view?usp=sharing Let me know if it doesn't work. I *think* I have the permissions set properly. I think I have the correct dcraw switches: dcraw -v -d -r 1 1 1 1 -4 -T path_and_filename.extension I'm using dcraw64 and this worked very well. No bayer matrix visible, completely monochrome and mapped into 16-bit space. I might have a flat from my experiments yesterday. I'll take a look and post it if I have it. Otherwise, I'll take a flat tomorrow. Tim

I saw the same thing. I used the DCRAW "document" mode for decoding, which does no bebayering at all. I've been scratching my head about what is the best thing to do with a monochrome image encoded in a RAW file designed for color images. I just tested the sensor late last night and have had no time for experimenting with the file. I gave the TIFF a very careful examination, but that was just to look for scratches and dead pixels. I found no evidence of either. I'll post a link to the RAW file when I get home. Tim

If anyone is interested, here is a link to the full-size image. The image in my first post is uncropped but downsized and jpegged. This is the RAW file that has only been run through DCRAW with the -d, -6 and -T switches. Those switches force no demosaicing, 16-bit output to a TIFF file respectively. http://www.timsroadster.com/pics/mono.tiff Tim

As a recent devotee to the DSLR Killer Klub, I though I would report my progress. I posted a couple of months ago about an idea I had to use abrasive blasting to remove the CFA. I successfully removed the glass using a simply soldering as posted in a previous thread. I bought a cheap "air eraser" which is much like an airbrush but is intended to spray abrasive instead of paint. It can be very precise and I though it would be ideal for removing the CFA if I could find an abrasive that was harder than the CFA but softer than the silicon dioxide optical pad underneath. The abrasive I chose to try is sodium bicarbonate (baking soda), and I started off at very low air pressure (15 psi). The baking soda is quite soft. So I tried it on a spare, partially broken but functional 550D I got off of eBay for $60. The results were truly amazing. It removed the microlenses and CFA almost instantly and didn't appear to harm the substrate at all. That was very promising. Sadly, when I put the sensor back in the camera, I got the dreaded Err 70. I figure that the abrasive action induced some static electricity on the face of the sensor. So, I tabled the abrasive blasting idea until I could think about it some more. I used the dead sensor to experiment with some of the "old school" mechanical removal methods. I settled on using aluminum as the scraper material. I took the shaft out of an aluminum pop-rivet, sharpened the tip, and chucked it in a pin vise so I would have very good control. I didn't bother with trying to epoxy the gold wires since epoxy shrinks as it cures and I think that has been the cause of some of the failures posted here. Used with a light touch, the aluminum tool seemed to do a decent job of removing the microlenses and CFA although I was having some difficulty with the CFA material smearing and then becoming very difficult to remove. Still, I thought it was worth pursuing. I found a lot of 5 broken 550D cameras on eBay for less than $200, and the seller said that all had intact sensors. So I took a chance and bought them think I would have 5 sensors to work with. After removing and testing the first sensor to ensure it was good (it was - they all are), I went to work on the scraping method. To help keep me from damaging the wires, I removed the hot mirror filter and re-installed the plastic holder. This covers the wires and also gives me a surface to hold the tool against while carefully working the edges face of the sensor. The results were less than satisfactory. I did remove most of the CFA, but some of it was smeared on the sensor face. I needed a method to remove the smeared material. Taking a cue from JTW, I tried some automotive paint polishing compound. I cut the tip off of a toothpick at an angle and flattened the tip a bit in some very fine sandpaper to make a polishing tool. The polish worked beautifully (3M Machine Polish Blue). I was able to polish off all of the smeared material even very close to the edges. I put the sensor back in the camera, and IT WORKED!. No obvious scratches, no dead pixels, rows or columns, just a clear monochrome image. Pic is attached. That's not the end of the story, though. During the time that I have been thinking about this, I have done a fair amount of research on the CFA. Information is limited, but from what I have read, I believe that the CFA is composed of photoresist material that has been dyed. The photoresist material is an epoxy-like material which explains its chemical resistance that has been documented here. However, in the semiconductor manufacture industry, they use a solution called "piranha solution" to remove photoresist. This solution is typically three parts sulfuric acid and one part 35% hydrogen peroxide. This solution will essentially dissolve any organic molecule, which the photoresist is. So, since I have 4 more sensors to play with, I intend to try it. I should point out that piranha solution is very dangerous to work with, but I fortunately have access to a fume hood and appropriate protective gear. I will only mix up a milliliter or so of the solution at a time, so the risks will be small. If this works as I anticipate, I should be able to completely debayer a sensor with zero damage to the sensor underneath (it is completely non-organic) in a matter of minutes. I ordered the hydrogen peroxide (it is conveniently available in 35% strength as a nutritional supplement) and picked up some sulfuric acid from the auto parts store (battery acid). So, the experimenting will continue. My hope is to develop an effective method to easily remove the CFA while leaving the sensor undamaged. I will continue to report on my progress. Tim

A few weeks ago, I outlined my proposed approach to debayering a Canon 550D. My approach will be to attempt abrasive "blasting" using an "air eraser" which is essentially an air brush that shoots abrasive instead of paint. I'll start out with simple sodium bicarbonate (often used as an effective blasting medium) and progress to more aggressive grits if necessary. The trick will be to find a grit that is hard enough to remove the CFA but softer than the underlying silicon. I'm ready to start and will report on my progress. Today, I overcame the first major hurdle - removing the cover glass on the sensor. I have read here about the problems doing that, so I took a very careful approach. To begin, I left the sensor in its aluminum cell so I could better hold it. I then used several sharp razor blades to scrape the adhesive that had squeezed out from underneath the glass around the perimeter of the glass. This squeezeout adhesive is mounded against the edge of the glass and represents the thickest part of the adhesive. I took care to completely remove this adhesive (using several razor blades to ensure a narrow, sharp edge) and even dig out a little bit from under the glass. The next step was to use a 60W soldering iron with a new chisel tip to heat the perimeter of the glass. I know that this has not worked well for some people here, and I didn't think it was working for me, but patience paid off. Using a magnifying light, I carefully placed the flat of the chisel tip against the glass. The important part here is the make sure that the flay of the tip is completely flat against the glass. The idea is to transfer as much heat to as much area of the glass as quickly as possible. I placed the tip against the glass for no more than 10 seconds (usually 5 or 6 seconds) - holding it in one spot for that time. I then moved the soldering iron to the opposite side of the glass so as not to heat one part of the sensor too much. Every minute or so, I stopped and waited a couple of minutes for the glass to cool. During that time, I worked the edge of the glass with the razor blade some more, being very careful not to work the glass too hard. At first, I didn't notice any effect - even after about half an hour of doing this. But with time, I started to see some color fringing (like you see on an oil slick on water). This told me that the glass was starting to separate. Patience here is key. As I started to see the color fringing, I would place the iron at the edge of the fringed area and it would grow slightly, still moving the iron around the glass, and stopping ever minute or so to let the glass cool and to work the edges more with the razor blades. With time, I had an entire edge showing the color fringing and I was able to work the tip of the razor blade under the glass. I resisted the temptation to pry and instead, just left the tip under the glass and went back to work with the iron. With the tip of the razor blade under the glass, things started to get easier since the tiny thickness of the razor blade tip was putting some upward pressure on the glass. After another half hour or so, I had color fringing around about 75% of the glass perimeter and was able to get the full thickness of the razor blade under one edge. At this point, I reminded myself that patience is a virtue. I didn't want to rush things and break the glass. Shards of glass could easily damage the nefarious gold wires. So I took my time and was able to eventually remove the cover glass intact. So, heat will work, given enough time and perseverance. It took me close to 3 hours. More to come... Tim

Greetings all: I have been curious about hte possibility of debayering a DLSR sensor for a while now and finally came across this thread. It seems that the entire world-wide knowledge base on the subject is contained here! I have read all 93 pages of this discussion and am amazed at the determination that some of you have exhibited. Kudos to everyone for being nearly the sole pioneers in the world in this endeavor. After reading of the successes and learning opportunities, I have given the idea of debayering a lot of thought. It seems like chemical methods have been largely unsuccessful at least on the Canon sensors. Physical scraping or abrasion seems to be the best approach so far. As I understand it, the microlens layer is easy to remove, ut the CFA layer can be fairly tenacious. Given the relative successes of several scraping and abrasion methods that leave the layer underneath intact, it seems like a logical conclusion that the CFA layer is a good bit softer than the layers underneath. This leads me to consider an approach that I use in my other hobby - auto restoration. The analogy is the removal of automotive paint without harming the metal, fiberglass, plastic or carbon fiber underneath. The parallels are undeniable. One method is chemical stripping. Another is scraping and abrasion (sanding) but by far the most effective method is media blasting. I'm left wondering how well media blasting would work for debayering. It would not requiring physical touching of the sensitive photosite layer and if the correct media and media grit is selected, I can imagine that it would quickly, easily and effectively remove the entire CFA layer while leaving the layer underneath completely unharmed. I would like to test this hypothesis and will eventually, but I thought I would share the idea here first, since right now my time is very limited and it may be a few weeks before I can get a chance to try it out. I would expect that an "air eraser", which is essentially an air brush designed for precision media blasting of small parts, would be the ideal tool. They are inexpensive and there are many grits and compounds available. I would expect that the work flow or media blasting would be similar to the more traditional approaches. I think the gold wires would need to be encased in epoxy to protect them from both the media and the air currents. I suppose one could then experiment with physically removing the microlens layer or trying to "erase" it with the air eraser. Given the descriptions of it being "gel-like" it may be more difficult to remove with an air eraser. The CFA layer on the other hand appears to be an ideal candidate for blasting. Since many of you have dead sensors laying around, you would have some good candidates for experimentation. Anyway, I think it is an approach that may have merit and I will experiment with it as time permits. Meanwhile, if any of you have an opportunity to try it out, please let me know how it goes. Tim