View Full Version : Odd strobing effect in EX3 footage


Brooks Graham
April 9th, 2010, 10:37 PM
Just got back from a gig and going through some B-roll shot on an EX3 and noticed this strange effect occasionally happening. It looks like what happens when you shoot an un-synced computer or video monitor, but it's not. When it happens, it happens for only a few seconds. My first thought was that something in the background was causing moire, but it happens regardless of background and in some of the shots, the background was way out of focus anyways.

It seems to happen at the beginning of a shot.

Here's a compressed example (I'll post the raw EX source file in a separate post as I'm having difficulties with attachments at the moment).

Any ideas?

I recently did the firmware upgrade and I'd hate to think that it's related to that, but you know how superstitions work.

Brooks Graham
April 9th, 2010, 10:47 PM
Sorry, couldn't upload the raw file, got some cryptic error.

Here's a link instead:

http://files.me.com/brooksgraham/waeisc.mov

David C. Williams
April 9th, 2010, 11:19 PM
Can't play it on a PC with the latest Quicktime version.

Brooks Graham
April 9th, 2010, 11:31 PM
Can't play it on a PC with the latest Quicktime version.

The H264 should play in Windows. I'd assume that you'd need the XDCAM EX codec available to play the raw file.

Also try VLC.

Alastair Traill
April 10th, 2010, 12:14 AM
I can play it on my IMac and MBP. The strobing effect does not extend to the highlight areas like the exterior or the drink waiter's shirt sleeve nor is it visible on the ladies chain patterned blouse. Does the strobing occur away from this area?

Brooks Graham
April 10th, 2010, 12:16 AM
If you look closely, frame by frame, you'll see that it does in fact appear on the waiter's sleeve as well as other the places.

And yes, it occurred away from the windows and in multiple other shots. It's very puzzling and worrisome.

Marty Welk
April 10th, 2010, 12:43 AM
what you provided clues to was just reported here in this forum a few weeks ago.
they mostly determined it was that 60or50htz shutter fixer thing, turned onto auto.

you know the shutter that is supposed to FIX flickering , when you get it, causes flickering at the first of the recording for some reason.
the solution was to take it off auto, then of course apply it manually when actually needed.

i would bet that you can fix the video if it was so hugely important, by using a temporal filter in virtual dub.

http://www.dvinfo.net/forum/sony-xdcam-ex-cinealta/473919-weird-problem-lines-first-secs-clips.html
see if this sounds familliar, i spend the first few hours with a new camera finding the evil AUTO stuff and turning it off, so anything that goes wrong was all my fault :-) that takes one screw-up out of the picture :-)

Brooks Graham
April 10th, 2010, 01:02 AM
I bet it's that. I looked on the camera in question and it was set to "Auto/50Hz". Ugh.

Like the poster in that other thread, I could have sworn that I had turned all that evil auto stuff off, but I must have missed that one.

Thinking back now, the room did have a mix of daylight from the wall of large windows and CFLs in horrid orange fixtures. Perhaps the auto flicker was getting confused because of the mix. (or should I say "auto flicker generator")

Well, that setting is off now.

Thanks for the pointer.

David C. Williams
April 10th, 2010, 01:13 AM
The H264 should play in Windows. I'd assume that you'd need the XDCAM EX codec available to play the raw file.

Also try VLC.

No, I've had this problem before. It's wrapped in something PC doesn't get. It's not H.264, it's re-wraped MPEG2 from. Here's the VLC output.

No suitable decoder module:
VLC does not support the audio or video format "xdv1". Unfortunately there is no way for you to fix this.

Annen James
April 10th, 2010, 08:52 PM
It's your flicker reducer FOR SURE. Turn it OFF. Not on auto. I had the same problems.

http://www.dvinfo.net/forum/sony-xdcam-ex-cinealta/473919-weird-problem-lines-first-secs-clips.html

Brooks Graham
April 11th, 2010, 10:59 AM
Yep. I'm completely convinced that the problem was caused by having the Flicker setting at the default "Auto/50Hz" setting.

Thanks for pointing it out. Thankfully there were only a handful of shots that had this problem and I can edit around them as they were just a bunch of candids. Thank goodness I caught this before it happened on something more critical. (and it's odd that it didn't happen on this camera before now)

Thanks again!

David Pryke
April 11th, 2010, 06:40 PM
It's your flicker reducer FOR SURE. Turn it OFF. Not on auto. I had the same problems.

http://www.dvinfo.net/forum/sony-xdcam-ex-cinealta/473919-weird-problem-lines-first-secs-clips.html

I second that....