Can long exposures affect your sensor?

I've seen a few friends of mine post that their images started developing excessive noise permanently after doing long exposures. Can it really affect your sensor like that? I've never had trouble with long exposures on mine, but I suppose every camera is different!

I hope not I love doing longer exposures! I've never heard of anyone complaining though. Is it they just noticed the noise more, or are they comparing old shots to new?

Seems unlikely. Electronics seem to degrade more due to heat and excessive current flow over time - and by time, I'm not talking about minutes, but months or years. I would expect an older camera which is powered up frequently to be more susceptible to degradation regardless of the length of exposures.

It is hard to find any supporting evidence on line that this is the case. Having said that, the use of the video feature in a DSLR can result in an overheated sensor. Whether such an event shortens sensor life or results in hastened deterioration also is not well documented. I do think long exposures can bring out the worst in sensor defects, making them more visible and hence the reason for the long exposure noise reduction algorithm.

See http://www.digitaltren​ds.com …verheating-dslrs/#!bxcaEa for some content on video and sensor heating. Although four years old the content in principle is still valid.

Video on a DSLR adds quite a bit more variables. I wonder how much extra heating is coming from the processor board (which is right behind the sensor) being heated from all the extra processing it's doing. If you google long exposures sensor damage, you'll see there's many articles and boards saying it's a popular myth. I don't see much evidence on why or why not a long exposure would damage a sensor....just more anecdotal experiences from photographers who do long exposures saying there's no change. Statistically, the camera that gets more fast shutter shots is going to break down faster (mechanical shutter is most likely going to wear out).

Your friends might also be seeing more noise after long exposures because they're looking for it It can be hard to judge noise performance in high ISO/ clipped DR scenarios that are different from one another.