C300: Magenta banding on c300 MKII: Is this a fixable issue?
- Thread starter Lkorver
- Start date
jm.gardiner
Well-known member
Unfortunately, it's a feature not a bug :/
In all seriousness, this is a known issue on CMOS sensors. I've gone back and seen it in footage I've shot on various red cameras. Though admittedly the mk2 def has one of the worst I've seen. I've sat down in engineers from canon and they're aware of the issue.
A few things I've done to prevent it:
- I did a test against some blinds a few months ago an found that just rotating the camera made it go away. Not always possible, but the problem seems to be most apparent when you have lateral highlights against an underexposed area next to it. X number of pixels at a certain IRE just strip out the green channel across a line.
- Exposure, One big thing to note with all of the Canon line, expose properly in camera, don't try to push the shadows around in post. I've found that magenta smear is worse when my shadow area is below 20ish IRE. I was getting into trouble when I was trying to balance everything in a frame, rather than exposing for the subject. Sometimes we try to play out post production in our heads a bit too much on set.
- If you've exposed properly most of it will go away in the grade. The frame you attached, if you gave it exposed +1 1/2 stops the banding would probably be a non-issue once graded.
Check out this example from a recent shoot. You can see the smear on the chair, but in this shot I've exposed for the subject in the chair so once graded it's imperceivable.
In all seriousness, this is a known issue on CMOS sensors. I've gone back and seen it in footage I've shot on various red cameras. Though admittedly the mk2 def has one of the worst I've seen. I've sat down in engineers from canon and they're aware of the issue.
A few things I've done to prevent it:
- I did a test against some blinds a few months ago an found that just rotating the camera made it go away. Not always possible, but the problem seems to be most apparent when you have lateral highlights against an underexposed area next to it. X number of pixels at a certain IRE just strip out the green channel across a line.
- Exposure, One big thing to note with all of the Canon line, expose properly in camera, don't try to push the shadows around in post. I've found that magenta smear is worse when my shadow area is below 20ish IRE. I was getting into trouble when I was trying to balance everything in a frame, rather than exposing for the subject. Sometimes we try to play out post production in our heads a bit too much on set.
- If you've exposed properly most of it will go away in the grade. The frame you attached, if you gave it exposed +1 1/2 stops the banding would probably be a non-issue once graded.
Check out this example from a recent shoot. You can see the smear on the chair, but in this shot I've exposed for the subject in the chair so once graded it's imperceivable.
Are you shooting Canon Log 2? If so, have you tried Canon Log 3?
