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I bought this used Canon 60D for a reasonable price, however, I get these purple pixels in the top right of my image. Even though I can work around it, it is very annoying. I've tried a lot of ways to fix it, like manual cleaning. I am trying to find another alternative than having to send my camera to Canon, as I don't have too much money to spend on repairing or a new one.

http://imgur.com/a/yQULL

Thanks in advance for any help!

Here's a full image.
full image

Here's a crop of the affected area.
crop of affected area

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    Could you post a hi-res JPEG to avoid compression artifact? It seems like dead pixels. Can you post an image of a grey or white uniform background ? – Olivier Aug 28 '16 at 10:06
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    If you go to the imager link you can enlarge the cropped view of the area and they are pretty easy to see. These are definitely NOT hot/dead pixels as they have irregular shapes many pixels in size, rather than the single dots or "cubic pyramids viewed from overhead" shape of hot pixels. They're also a uniform color that is not one of the filter colors of any RGB sensor I've ever seen. – Michael C Aug 28 '16 at 20:37
  • Is it possible that some kind of transparent magenta dust is on the sensor glass? – trognanders Aug 28 '16 at 23:26
  • @BaileyS It would need to be under the glass to be that sharp with the wide aperture it appears was used to shoot the example. – Michael C Aug 29 '16 at 5:55
  • @MichaelClark They do seem pretty sharp and bright to show in the demo picture, I agree. Pretty strange stuff though, since they are too big to be single dead pixels, and pretty organically shaped to be damaged electronics. – trognanders Aug 29 '16 at 18:47
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It's near impossible to tell exactly what the spots in your picture are. It is fairly easy to look at them and eliminate what they are not: hot or dead pixels.

Due to the sharp outlines and well defined irregular shapes of the different spots it is fairly safe to say that they are on or very close to the actual sensor itself, and not on top of the stack of filters that lie directly in front of the sensor. If they were on top of the entire sensor stack at the very wide aperture with which the example image appears to have been taken they would be very blurry and indistinct, rather than sharply defined. They might even be an effect of some sort of internal sensor damage that affects the readout of the sensor.

It's just a guess but I think it may be possible your camera might have attended a "color run" or similar event in the past. When colored powder got into the camera someone tried to clean it. In the process some magenta colored powder seems to have been moved under the sensor stack into the surface of the sensor itself where it is now trapped between the sensor and the filters that cover the sensor. The fact that the problem area is very close to an edge supports this theory.

You might try to reduce the effects of the spots by following the procedure outlined in your EOS 60D Instruction Manual (pp.231-32) for recording and applying dust deletion data. Once you do that the camera will apply the dust deletion data to jpegs produced in-camera when that option is selected in the camera's menu.

If you save the raw data files and want to automatically apply the dust deletion data when editing on your computer you can use Canon's Digital Photo Professional to convert the raw files. Version 4 of DPP is quite good, includes more features, and has a more user friendly interface than the previous versions. I prefer using DPP to convert the raw files from my Canon cameras. It seems to me that the colors can be more finely controlled than with third party tools such as Lr/Ps or DxO.

Since the spots all seem to be a rather uniform magenta in color, you might also try to reduce the magenta by using the Hue/Saturation/Luminance (HSL) tool included in many photo editing applications. If the photo you're editing has no other instances of magenta in the frame you can reduce the saturation for magenta to zero and then adjust the luminance value to blend it in with the surrounding area.

If that doesn't work you can try to manually repair each spot with a "healing" type of tool that converts spots to the average color of the surrounding area. Most such tools allow you to specify the size of surrounding area from which the color is averaged.

Ultimately I don't think you'll be able to totally remove the effects of these artifacts without replacing the sensor.

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These are irregular shapes and my guess is that they are not pixels, but drops of some purple liquid. If you set your camera to the cleaning mode, remove the lens and inspect your sensor with loupe and a flashlight. When you try to locate the spot on the sensor, don't forget that the image is recorded upside down.

  • If they were on top of the sensor stack the shapes would be blurrier at all but the narrowest apertures. The example image does not appear to be shot at such an aperture, in fact it appears to have been shot at a fairly wide aperture. If a foreign substance is causing this it is on the surface of the sensor or bayer mask itself and underneath the IR and UV filters and the low pass AA filter, not 1-2mm away on top of them. – Michael C Aug 29 '16 at 5:44
  • @MichaelClark Possibly. Visual inspection of the sensor will tell more. – MirekE Aug 29 '16 at 15:23
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Edit: see comments

These look like "hot" or dead pixels. It's quite common for sensors to develop a small number broken photosites during their lifetime - these will commonly show up as single pixels of a very bright single colour, or sometimes as a completely black pixel - no amount of cleaning will solve this problem.

The RAW-JPEG conversion done in some camera models will remove these by interpolating the values from surrounding pixels, and the same can be done in many RAW processing applications during post-processing. This can mostly be done automatically (e.g. in darktable, you can add the "Hot Pixels" plugin to a profile, and then apply this to all images - it will automatically detect the dodgy pixels and hide them).

The only way to get rid of them for all images is to replace the sensor with a working one - whether this is worthwhile in a second hand camera is questionable given how easy the issue is to fix in post-processing.

The fact that your sensor has developed several close together suggests that it was caused by damage to the sensor rather than sporadic failure.

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    The affected areas are way too big to be hot pixels. – Michael C Aug 28 '16 at 20:21
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    @MichaelClark - on closer inspection of the image, I agree - initially I thought that the patterns looked like clusters of single pixels - but actually they have blurred edges which suggests theres an area affect which you wouldn't expect. It's possible (but unlikely) that this is still clusters of hot pixels which post processing have blurred, so I'll leave this answer here until the full resolution image is posted. – Harry Harrison Aug 28 '16 at 20:26

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