Dead pixels???

[Rainey]

I have just noticed after taking several night shots tonight that I have a few dead pixels (I assume) on my sensor. My camera is a Canon 350D and only about 5 weeks old, I wouldn't expect this to occur so early in its life. Is there anything that can be done about it, or should I just return the camera to the store and ask to exchange it for another one?

[Kyle]

How long was the exposure? They might have overheated, hence showing bright?

[Rainey]

They were 30 second exposures, I did a fair few of them tonight but even the first couple of shots that were only 5 - 8 seconds had the pixel on the right side.

If they overheat would they come right again?

[Rainey]

Hmmm okay I shot a couple at <1sec exposure and they are clear???

With another 30 second exposure of a dark room I get exactly the same pattern! Will warranty cover this? I've handled my camera with extreme care 100% of the time.

[whiz]

Doubt they'll do anything about hot pixels. Check your manual carefully and you may find mention of this phenomenon. My D70 had five of them. Only discovered it had some when I was doing long exposures.
I fully expect that my D200 has some too.
Almost any editing program will fix this, so don't go slashing your wrists just now.

[gstark]

Rainey,

This is not a major problem. I know you think otherwise at the moment, but ...

First of all, and as you've seen, it's only occurring with longer exposures. Thus it seems as though it may be heat related.

It may be that you can map the sensor in the camera's firmware; I'm not sure. I think we can do this in the Nikon's; I don't know about the Canon.

But importantly, it's only happening to one or two specific pixels. It's more an issue when you pixel peep, which is something that we all tend to do. The reality is that, when you're printing an image, you don't normally get to print at an individual pixel level, and thus the problem is masked.

Unless you're printing super large prints, you will never see the problem in any printed image, nor will this issue manifest itself in any real practical sense.

[ziggy]

I think the Canon 350 , unlike a 300 has a noise reduction feature in the menu somewhere. What that does is a dark frame subtraction for long exposures - ( I consider over say 4 seconds to be a long exposure for a digital sensor)

This behaviour is quite normal

[Rainey]

Is that big group of hot pixels on the left hand side normal as well? I'm just almost sure it wasn't doing this last time I had the camera out, I've been over my last group of shots (the Lotus) and can't see any sign of it.

I know photoshop could easily fix the shots but I'm still a little disappointed, mainly with that big dot. I noticed on shorter exposures it just starts to turn purple as it 'heats' up?