Noticing a dead pixel in my video. Camera, or Lens?
 

Hi.
I recently completed a short film. I shot with the T2i, and Canon 50mm 1.8.

When the screen is dark enough, I'm noticing a very small, purple, dead pixel. I'm hoping this is a lens issue, as the lens is much cheaper than the camera.

Anyone have an idea what this is, how to repair it, or why this may have happened. I've had the camera and lens just about 6 months, but neither have been used heavily.

Thanks in advance.

Is it on the footage?

I've got a dead pixel on my LCD screen but that doesn't show up on the footage obviously.

Yeah, Mine's on the footage. Uploaded to vimeo, on several different computers.. anywhere.

Well it's hard for us to diagnose the problem without seeing any images of it, but dead pixels on DSLR's are not altogether uncommon.

A simple way to test if it is the camera of the lens is to change lenses. If you don't have any other lenses, then I'm sure you can find a friend who'll lend you one to test out.

It doesn't sound like a lens issue because dust/scratches on the lens would not be purple (even if it is purple dust, because it will be backlit the whole time) and it would change sharpness and appearance as you change aperture or adjust focus.

Is the camera still under warranty?

I thought I had a dead pixel when I first got my 550. It turned out to be a dust particle that couldn't be cleaned with the built-in sensor cleaner. I just lifted the mirror and blew it out.

I can't remember if the T2i has manual cleaning or not, if it does, follow the instructions on the manual cleaning and it should fix it for you.

If it is a dead pixel, go to manual cleaning, put the lens cap on and let it reset for a minute. You can also send it into Canon and they have tools to reset the sensor. I use cc wireremoval in after effects to get rid of the dead pixel.

I took some video with the lens cap on, as it's more noticeable the darker the screen is. Here is the screen shot.

To my horror, I discovered not only the original culprit, but also many many others... not as luminous, some more purples and a few faded reds.

I tried the "clean now" setting. It said it was cleaning the sensor, then took me back to the menu. I'm having card issues now... I will inspect the footage as soon as possible.

Looks like you didn't post the screenshot. Been a long day? :)

Correct me if I'm wrong, but isn't that just noise that you're seeing in that picture?. Canon 7D ISO versus noise test images Marvelsfilm’s Blog

Well, I'd feel mighty foolish if that were the case. But I don't believe it is. There is some noise in the image as well, but I am concerned about the small bright purple square in the bottom of the frame, near the center but slightly to the left. I called Canon with the issue, they're recommending that I ship to them for repair.

I think you ran the auto cleaning. Look in the menu and you should see "manual sensor cleaning", third option down. The camera will not send you back to the menu. You will have to do a hard reboot.

Ah, that is what I did indeed. Thanks for the clarification!

I just noticed what appeared to be a white dead pixel in some footage I shot using a few different lenses. I did the manual sensor clean from the menu and it seems to have gotten rid of it. I just assumed the sensor cleaned itself after every shut down but perhaps this is a more robust / aggressive clean?

Just in case anyone else finds themselves in panicville :-)

Re: Noticing a dead pixel in my video. Camera, or Lens?
 

Cole --

I had the same thing (dead/red pixel) -- in almost the exact same spot. I returned the camera to the shop I from which I bought it (within the store's return time policy) and received a new camera. All is well with the new one.

Return it if you can!