Interlaced artifacts in 24P

Jason McKelvey · October 6, 2004

I had our editor do some frame grabs from some footage I shot with the 900. It was in 24P with V.RES set to INTRLCE because we don't do film-outs. I expected the frame grabs to look like film frame grabs... like a still photo. Instead, even with my subject perfectly still, there was interlace artifacts on the edge of his nose... like a jagged edge. Is this because of the V.RES setting? Will setting this to PROG make a difference? When I freeze my DVD player, it looks like a clean frame grab. Is there a way to get this type of performance out of our 900?

Thanks,

Jason

Phil Rhodes · October 7, 2004

Hi,

Yup, that's interlaced!

Phil

Jason McKelvey · October 7, 2004

Thanks Phil. :wacko:

John Ealer · October 7, 2004

Even if you shoot 24p, you're still going to have judder from the 3:2 pulldown if you capture your footage at 29.97. What I think you're looking at is simply that.

If you want to have completely clean stills, remove the pulldown in your edit box and work in a 24p timeline.

Changing to V.RES PROGRESSIVE wouldn't affect these issues at all, just potentially introduce another source of aliasing.

J

Rob van Gelder · October 7, 2004

Photoshop -- select "filters" ----> video ----> de-interlace ----> voilá :)

Jason McKelvey · October 8, 2004

Thanks, one more question; how then do the freeze frames on my DVD player look sharp and not interlaced, even though I use a standard CRT TV?

Jason

Phil Rhodes · October 8, 2004

Hi,

Because your DVD player is deinterlacing them. Most digital video devices have the responsibility of delacing freeze frames so they don't flicker like mad between one field and the previous one.

Phil