Purple dot on video/display? Should I return the camera?

Hello! Newbie here. I have a problem with my brand new Canon EOS 6D.

 

Purple dot appears on video (shot under low light) and it's also visible on display (live view mode).

 

I'm not certain if this is a pixel because if I zoom in the video on my computer, the purple dot seems to occupy more than just one pixel. Here are the images:

 

Video zoomed in:

https://ibb.co/cJfQ5o

https://ibb.co/mM9Gd8

 

Video normal size:

adfdsf

 

Should I return the camera? I'm not an experienced user, so before checking out the tutorials on how to fix this, I'd like to know if this is a serious problem or not. Any advice?

Hi Miajx, old experienced Canon camera shooter here. Welcome to the Photo.net Canon EOS forum.

 

Looks like you have a hot pixel, cameras get these, both hot pixels and dead pixels and stuck pixels. Nothing to panic over. You just need to remap your sensor. It is simple to fix. You can do this by removing the lens and putting the camera body cap on the camera, then go into the camera menu and go to the sensor cleaning menu and press clean sensor manually. This takes about 30 seconds. Your camera looks at every pixel on the sensor checking for hot, dead or stuck pixels. If all goes well you will not see the purple spot anymore. If this does not work after several attempts, then consider returning the camera or sending to Canon for repair.

 

It sure beats editing these out of every photo. It happens to all cameras.

 

Let us know how you make out. :) And hope you become a regular participant of the Canon EOS forum.

Edited May 26, 2018 by Mark Keefer

Looks like you have a hot pixel...

 

It sure beats editing these out of every photo. It happens to all cameras.

 

Hmm... except film cameras...

http://bayouline.com/o2.gif

Hmm... except film cameras...

:rolleyes:True unless you have the special hot pixel film. And in that case, this manual sensor cleaning fix would not work for that film. Film shooters are at a real disadvantage there.

:p

:rolleyes:True unless you have the special hot pixel film. And in that case, this manual sensor cleaning fix would not work for that film. Film shooters are at a real disadvantage there.

:p

 

That's my experience as well, esp as just about any film over 1600 ISO DEFINITELY falls into that category... ;)

The likely reason it takes over more than one pixel (on the RAW) is because with modern pixel dense sensors, the physical sensor 'bleeds' the hot pixel to the readout of surrounding pixels, causing the A/D convertor to see a higher analog value in surrounding pixels (which then gets converted to higher Digital values in the file)... ...that and if this is a jpeg (not the raw), the Raw->jpg algorithm, tends to feather out hot signals as well... I would compare this to the RAW to see which pixels are actually being affected (sometimes it is literally only the one)... ...but only if you care about esoteric information... ;) the fix is still the same... what Mark posted...

Let us know how you make out. :) And hope you become a regular participant of the Canon EOS forum.

 

Yep, manual sensor cleaning worked! The dot is gone! Thanks a lot, Mark! :D And thanks for the detailed explanation! It's my first cam and I'm just starting to learn, so it really got me worried.

 

The likely reason it takes over more than one pixel (on the RAW) is because with modern pixel dense sensors, the physical sensor 'bleeds' the hot pixel to the readout of surrounding pixels, causing the A/D convertor to see a higher analog value in surrounding pixels (which then gets converted to higher Digital values in the file)... ...that and if this is a jpeg (not the raw), the Raw->jpg algorithm, tends to feather out hot signals as well... I would compare this to the RAW to see which pixels are actually being affected (sometimes it is literally only the one)... ...but only if you care about esoteric information... ;) the fix is still the same... what Mark posted...

 

This happened only on video. I haven't noticed any problems with photos so far but I'll test that out if I notice something. Thanks a lot for the tips! :)

Yep, manual sensor cleaning worked! The dot is gone!

Great, good to hear the spot is gone. Thanks for getting back to us.

This happened only on video. I haven't noticed any problems with photos so far but I'll test that out if I notice something. Thanks a lot for the tips! :)

 

You might not ever even see it on full resolution RAWS viewed fully on screen (you'd pick it up viewing at 100% - if looking in the right place), as, likely -at most- it's going to be no more than ~9 pixels affected (though possibly much fewer). I recall having a hot pixel pop out of nowhere on my old 400D (picked up as solid red), and the only reason I saw it was because I was reviewing RAWS, it was bleeding about an extra 128R to the surrounding pixels, but even most exported JPEGs ignored it completely (except on very dark backgrounds). Video encoding however includes downrezzing, and my understanding is that it behaves considerably differently since it is simultaneously downrezzing to 1920x1080. It very well may see a group like that (or even one if it happens to be the lucky pixel picked), and instead of outputting a single pixel at 256, output a group at 128 (or some thing similar)... I'm certainly no expert on video encoding algorithms...

With the old GAF 500 slide film, shot at ASA 500 or higher, pretty much every bit of grain (analogous to pixels) was a "hot spot"