Hot pixel on 20D, what to do?

Posted: Sun Apr 24, 2005 1:43 pm

I took a 20 second night shot and noticed a hot pixel on my 20D.

Is this common?

Does Canon warranty a single hot pixel? If so, should I bother sending it back?

Posted: Sun Apr 24, 2005 2:08 pm

This comes up on other forums a lot. A few hot pixels in a long exposure is pretty common, I understand...

If it's a "dead pixel" - ie, it appears at all exposure times, I think canon will either fix it or not depending on whether it's in the center portion of the frame or not (based on some percentage of the total image, not sure what the number is) - this is rumor from another forum though.

Posted: Sun Apr 24, 2005 3:08 pm

There are a few, but the shot below shows the worst one. The same area is shown at 500%.

The shots were taken at ISO200, f/22 with the lens cap on and the eye piece covered. Starting from the bottom left continuing clockwise, the time in seconds are 30, 20, 10 and 1.

They appear to lessen as the time decreases. I assume this would be a "hot" pixel, and is to be expected?

Posted: Sun Aug 28, 2005 6:19 pm

I discovered that I too have this problem on my 20D. Havent done any tests on if it is better or worse with prolonged exposures. Is there a way to fix this other that sending it into canon. I wonder if it is under warranty. Why or how does it occur. I am quite certain it wasn't there before. Anyone have any experience?

I went back and looked at some past images and it turns out it has been showing up since early June, seems to be more apparent now as if it has become more sensitive to light.

Posted: Sun Aug 28, 2005 7:25 pm

You're going to get a few dead pixels during the life of the sensor. I don't think Canon is going to give you a new sensor, though.

Posted: Sun Aug 28, 2005 7:31 pm

I guess I will have to just remember to clone out the hot spot before I print. I am sure I am well over the 100,000 shots which means it isnt under warranty anyway. dang

Posted: Sun Aug 28, 2005 7:52 pm

I've got a couple of those on my 350D. Actually on both 350Ds I've owned (returned one due to a faulty autofocus display in the viewfinder). They aren't as much of a problem as the mysterious red/blue blobs that sometimes show up at really long exposure times, but those are easily dealt with by turning "long exposure noise reduction" on in the custom functions.

Posted: Sun Aug 28, 2005 8:10 pm

Quote:

I don't think Canon is going to give you a new sensor, though.

I agree, they won't replace the sensor, if it's under warranty they will map it out for you. Basically they take information from the surrounding pixels to interpolate what that one dead pixel should look like.