Werid video highlights burnout artifacts !?!

typo on... weird* my bad

anywhoo, ive been shooting a fairly big night project for an important client. Ive been starting to noticing allot of weird burnout highlights or bright flickering artifacts on sharp edges that are in focus. They also kinda flicker and pop out during movement. I dont really know how to explain them.

All the clients footage is properly exposed. We used nikon lens with adapters and LED dimmers to constantly maintain 1/50 shutter and 2500 iso for every shot.

I cant post the actual footage due to NDA papers but i have found a shot from something else that shows the problem... Im going to post more a few more shot as i have to recreate the scene to explain this issue better.


heres a raw still frame example from a mov file.
http://www.ozan.ca/mk2/frame_1a.tif

anyone?

[Mark Hahn]

Originally Posted by Daniel Browning

Those are aliasing artifacts.

When the bus first starts to come into focus, its front grill (and only the grill) is covered with green and orange aliasing. Don't see any blue in the aliasing though. Even though I just calibrated my monitor, it is cheap and the green I see might be blue on another monitor.

[Daniel Browning]

Originally Posted by Mark Hahn

When the bus first starts to come into focus, its front grill (and only the grill) is covered with green and orange aliasing. Don't see any blue in the aliasing though. Even though I just calibrated my monitor, it is cheap and the green I see might be blue on another monitor.

I see green and orange too.

[Ozan Biron]

Originally Posted by Daniel Browning

Those are aliasing artifacts.

ya dats what i figured...

http://www.ozan.ca/mk2/MVI_0243(00122).jpg (Zoom closer to see those blue/green lines)

Soo what do i do know? Its soo bad in a few shots that the client aint to happy. Jst sounds liek alot of reshoots.

Is there anything i can do to try to prevent this? Bring down sharpen in the menu? Use another preset?

[Mark Hahn]

Originally Posted by Ozan Biron

ya dats what i figured...

http://www.ozan.ca/mk2/MVI_0243(00122).jpg (You have to zoom closer to see those blue lines)

What you call blue, I call green, and except for the brief serious bus grill problem I'd have no problem selling that footage. Most of the thing your arrows point to, fall into the "pixel-peeping" category. Any particular one, except for the bus grill, could be touched up pretty easily but I wouldn't take the trouble.

[Daniel Browning]

Originally Posted by Ozan Biron

Bring down sharpen in the menu?

There will still be a ton of aliasing even with sharpening down all the way. Presets cannot fix this problem.

Originally Posted by Ozan Biron

Is there anything i can do to try to prevent this?

One unlikely possibility is to use a camera that does not skip 2 out of every three lines, and therefore doesn't suffer so much aliasing.

You can try to blur it in post. That will smear the false colors and false detail, which can help the harsh jagged edges and make the aliases a little less attention-grabbing, but they will still contibute to the image in a negative way

But a more likely solution will be to add an optical filter to the front of the lens that will blur the detail enough to remove the worst aliasing. Hopefully it will only knock your effective resolution down to 720p or so. Jon Fairhurst has already tested several filters, but no one has reporting finding the optimal filter, yet.

[Mark Hahn]

Originally Posted by Daniel Browning

There will still be a ton of aliasing even with sharpening down all the way. Presets cannot fix this problem.



One unlikely possibility is to use a camera that does not skip 2 out of every three lines, and therefore doesn't suffer so much aliasing.

You can try to blur it in post. That will smear the false colors and false detail, which can help the harsh jagged edges and make the aliases a little less attention-grabbing, but they will still contibute to the image in a negative way

But a more likely solution will be to add an optical filter to the front of the lens that will blur the detail enough to remove the worst aliasing. Hopefully it will only knock your effective resolution down to 720p or so. Jon Fairhurst has already tested several filters, but no one has reporting finding the optimal filter, yet.

And of course, you can touch-up the obvious ones.

[Robert Sanders]

Looks like chroma aliasing artifacts to me too. They don't look like deal-breakers though.