View Full Version : flicker DEFECT


Saul Martinez
October 10th, 2006, 05:08 PM
I am having some distracting flicker in my shots with the HD100U specially when panning on leaves or subjects with thin lines. Have somebody experimented this? What could be the reazon? Could it be fixed?
Thanks for your advise.

Steven Thomas
October 10th, 2006, 05:32 PM
hmm.
never heard of this.
give us a link to a small file showing us what you're seeing.

Saul Martinez
October 10th, 2006, 07:02 PM
I attached two Qt, one is the original shot where the the kind of flicker effect
is light and the other shows how it is evident when a slowmotion effect is applyed. (Avid XpressPro). Thanks.

Stephan Ahonen
October 10th, 2006, 09:05 PM
Is this standard def? You are probably seeing interlacing artifacts.

Saul Martinez
October 10th, 2006, 09:29 PM
yes, I am rec in SD. What do you mean with interlacing artifacts?

Stephan Ahonen
October 10th, 2006, 10:08 PM
I'm not sure what you mean here, if you're asking what interlacing is, this is a basic video term that all videographers should be familiar with. It refers to scanning the even and odd lines of the image alternately instead of sequentially. Interlacing artifacts are any visual errors introduced by interlacing. Interlacing makes very thin lines flicker because they are only being refreshed half as often as the picture as a whole appears to be. This is an effect common to all cameras which capture interlaced video, not just the HD100.

Saul Martinez
October 10th, 2006, 11:59 PM
Stephan, is there a way that I could correct this on my JVC?
Thanks for your advise.

Jack Walker
October 11th, 2006, 12:10 AM
Stephan, is there a way that I could correct this on my JVC?
Thanks for your advise.
Correct me if I'm wrong, but:

The interlacing artifacts are inherent in the format. Since alternating lines of video are captured at different times, thin moving lines (in the picture) will be broken up because the entire line is not captured at the same time. There will be misalignment as the line moves between the captures of the alternating video lines.

Shooting in progressive mode will not show these artifacts, since the entire frame will be captured at once.

The camera shoots HDV progressive frames -- that is, the entire picture is captured at once, not half the picture, then the other half the picture (in alternating lines down the frame). The camera also shoots SD 16:9 progressive frames.

As I am trying, try 50p (PAL) or 60p (NTSC) and you shouldn't see this. You will still get the SD picture (16:9) but without interlacing.

I do not mean to give a full explanation or solution, but perhaps a different way to look at it.

Saul Martinez
October 11th, 2006, 09:15 AM
Thanks, Jack and to all. I learned a lot.