Dead Spots on a Sensor

[Tyz1on]

If a sensor develops a dead spot on it can anything be done? I have a feeling the answer is no but thought I would float it out there.

The camera works fine but when the pics are viewed, on three different photo programs, there are three dead spots that look like this

[P1X4R]

i did a quick search for dead pixels. this seems interesting

http://www.starzen.com/imaging/deadpixeltest.htm

[Tyz1on]

Thanks Ed, I'll run the test tonight and see how it turns out.

[Tyz1on]

Well I ran the test at several exposure speeds and here are the results:

@ 1/30 second - 0 dead pixels and 0 hot pixels
@ 1 second - 0 dead pixels and 1 hot pixel
@ 2 seconds - 0 dead pixels and 3 hot pixels
@ 3 seconds - 0 dead pixels and 2 hot pixels
@ 5 seconds - 0 dead pixels and 4 hot pixels

So the good news is I have no dead pixels. The bad news is that I have hot pixels, but the really good news is that I found out how to "fix" the problem.

Put the lens cap on the camera.
Go to menu - shooting menu 2 -sensor cleaning - manual - OK
This will lock the mirror up
After 30 seconds turn off the camera and the mirror will return to its normal position
Take a shot and check for your pixel.
Apparently this is an undocumented feature of the xt, xti and xts
The camera tests for stuck pixels and maps them out by replacing its value with the average of the surrounding pixels.

Apparently it won't work in all cases but its worth a try before sending it to canon for fixing.

It worked for me no more visible hot pixels.

This what the problem looked like but the bad spots are harder to see on this resized pic. There was a third hot pixel on the upper right portion that didn't even show on the jpeg

[HoldyourfireAl]

I'm so glad we have this section for important info like this!

[P1X4R]

are you going to send your camera back for repairs? warranty work?

[Tyz1on]

Originally Posted by P1X4R

are you going to send your camera back for repairs? warranty work?

From what I've read Canon would probably do what I already did which was remap the sensor. I guess it takes the hot pixel and remaps it with an average of surrounding pixels. Whatever it did, it worked. The hot pixels are gone now.

Another thing that I found out was that there is a much greater chance for hot pixels to show up if you are taking long exposure pics. My wolverine pics were taken in a fairly dark room with forced a ISO of 100. Some of the exposures were in the 6-7 second range.

Oh I should also mention that this problem arose on an Xsi, not an Xti. I kind of accidently bought an Xsi as well.

[P1X4R]

don't forget to accidentally buy a few lenses as well.

as for the hot pixels showing up on long exposures.. sometimes my shots can take up to 30secs in very low light conditions.. i have yet to see any. [knocks on wood]

i still need to run that program though to check.