compression artifact or something else?

during a recent photosession, this dot appeared on every photo in the exact same location.
camera is a g1, jpeg superfine, and program mode

in other pictures, i've seen more dots, but this time it was just one dot. i'm wondering if it's due to some error in the camera or software, or is it a defect with my lens?

here is a pic for reference:

Byte size: ZERO | Content warning: NOT AN IMAGE

I read in a different post someone having a similiar problem, but the problem was not there when they shoot in raw... does this happen with you too? Perhaps the problems are related.

Duff pixel

i'm pretty sure they happened in raw too, but i may have used longer exposure times too (i read something about how using 1-2 sec exposures can cause artifacts)

what does that mean?

That one spot of green has died and will probably always be green, it wont show most of the time though so dont let it get to you.

Which raises an important question, is this kind of problem defect pixel typically inherent in all digital camera?

There are a mess of threads here regarding hot pixels, stuck pixels, and dead pixels. Looks like the one above is a hot pixel. You can check by taking a picture in a pitch black room, or if you're lazy and gentle (like me), just lightly press the lens cap over the lens and take a shot.

Nabil-A, you're right, it's an inherent problem in sensors. You can generally assume that every sensor will have defective pixels, even when brand new. In new cameras, they are generally mapped out by the manufacturer before shipping, stored in non-volatile memory of some sort, and then compensated for by the camera (it uses interpolation from surrounding pixels to populate the defective pixel). As the camera ages, more may develop. The warmer the sensor is, and the longer the exposure is, the more obvious these defects will be. If you're not seeing them in exposures shorter than 1/4 second, I wouldn't worry too much, unless you mostly shoot that speed or slower.

There's a tiny utility you can use to process an image and see what kind of defects you have:
http://www.starzen.com​/imaging/deadpixeltest​.htm
But read the warnings for your peace of mind--you're probably going to find defects, and that's not necessarily bad.

If your camera is under warranty, you can send it in if you wish--definitely check out some of the threads here for other folks' experience with that.

It's also possible to automate the correction of those pixels when you've mapped out their location.

yep, i guess it's a hot pixel
i saw the same spot when i did the lens-cap test

also clean the lense really good ... I get these all the time in different spots due to tiny dust particles