5D MK lll Dead spot

[Lepus]

Hi all , I noticed this a while back , and I don`t see it on all images , but now and then a tiny pinky coloured spot appears on my raw files , I was told this was a dead pixel and not uncommon . It`s not hard to get rid of but is annoying , has anyone got any words of wisdom on this ?

[the black fox]

Re: 5D MK lll Dead spot

Never heard of that before with cameras mark ,is it still under warranty

[ST-EOS]

Re: 5D MK lll Dead spot

Have a look at this link (there are other references on the web)which discusses the issue and suggests a fix.

http://www.bluehoursite.com/articles/how-get-rid-stuckdead-pixels-canon-dslr-camera

Sent from my iPhone using Tapatalk

[Enigma]

Re: 5D MK lll Dead spot

Have you installed latest available firmware? Have you cleaned sensor? Does it show on both raw and JPEG images? Is it dependent on ISO? Is it dependent on shutter speed? Is it visible if you take a shot with lens cap on? Is it dependent on lens? Does it show as single pixel if you view 1:1?

Just throwing a few options at you to see if any of them might either eliminate or point towards a cause ... I'm not entirely convinced (but willing to be proven wrong) that a single dead pixel would result in a consistently coloured mark on images because individual pixel colours are derived from groups of adjacent pixels.

Edit: Peter's suggestion definitely worth trying first - I vaguely remember this solution from my 20D and 5D days.

[Dave_S]

Re: 5D MK lll Dead spot

This not an unknown issue with CMOS sensors, although it is more prevalent with CCD's.

What you are seeing is more likely to be a 'Hot Pixel', as opposed to a 'Dead Pixel', which would be appear black.

It could be a group of adjoining pixels, as individual pixels are very small, and a single 'Hot Pixel' may not be visible in an image.

Not the case with astro-imaging cameras, that generally use CCD's as opposed the CMOS sensors, where against a black sky background, 'Hot Pixels' appear as white specs, and can be numerous. Most astro image processing software, includes a 'Hot Pixel' filter removal filter.

It is difficult, if not near impossible to manufacture sensors, without any hot or dead pixels, but as isolated individual faulty pixels are so tiny, as to go unnoticed in a normal (terrestrial) image, they are considered acceptable by the manufacturers.

Its only when a there is a group of adjacent hot or dead pixels that they become noticeable, as black or saturated (light) spots in an image.

If the camera is still under warranty, then it would be worth sending back to Canon, as if the number of faulty pixels exceed the acceptable standard, the sensor should be replaced.

If not, it would not be worth the considerable expense of having a senor replaced, especially a full frame one, as the problem is easily removed during processing.

Dave

[Iron Man]

Re: 5D MK lll Dead spot

On my original 5D, I had a small bunch of dead pixels (about a dozen or so, out of warranty). However, I only ever noticed them when photographing the sky or other bright scenes. One small click with the healing brush in PP and all was well, so it never really bothered me - you learn to live with it.

[El Sid]

Re: 5D MK lll Dead spot

I used to have a hot pixel on my 40D from new which tended to show up as red or occasionally green but it doesn't seem to be there any more - either it died (but I don't see a black one either) or the camera has somehow mapped it out(?)...

Was never a great bother one click of the spot healer and it was gone.

[Lepus]

Re: 5D MK lll Dead spot

Thanks for all the replies , think my warranty is out Jeff , I have only noticed it at odd times , and I have a feeling it`s always been at higher iso settings , oddly I used it today under similar light with same lens ect , and I have not found it on today's images , it`s the second time I have noticed it in months , I think I did the self sensor clean last time , weather that worked or was a fluke who knows ? But will do that again , and upgrade the firm-wave . Hope that`s not to hard never done it before .

[Enigma]

Re: 5D MK lll Dead spot

and upgrade the firmware . Hope that`s not to hard never done it before .

Not difficult, just series of steps to follow. In summary:

Check Canon site for latest version
Check camera for current version - if same then no further action, else continue below
Download latest firmware to computer
Unzip download to get the file you need
Copy to root of a memory card
Ensure your battery is well charged
Remove any other card from camera so only the firmware card is in
Navigate to firmware upgrade menu and follow instructions
Upgrade only takes a few minutes
Once upgrade has started, do NOT touch any camera controls until it finishes

There are much more detailed instructions available but that's the basic procedure

[Lepus]

Re: 5D MK lll Dead spot

Thanks Enigma , Just updated the firmware , that`s a first for me , fingers crossed but all appears to have gone as planned , time will tell .