Anyone noticed a weird interframe flicker/strobe on 7D panning shots?

Regarding interlace problems with progressive footage I can submit this observation: when doing motion graphics for broadcast I often get handed still photographs in rather large resolutions - when I scale those down in a After Effects composition and do slow movements across them in pure 25 fps progressive they display a flicker very similar to the one described here, especially if the photos contain grain. I can either fix it by setting the composition to 50i or - which I prefer - add a interlace flicker filter on top of the final output. The progressive image created this way is simply just a tad to sharp for displaying on a interlace monitor and therefore needs a faint vertical blur to blend the two fields together. Seen same thing on 16 / 35 mm telecined material as well but not as distinct.

Could also be as suggested a rolling shutter problem, ie; the time difference between each line when the scan rolls down makes enough difference between the fields to cause interlace fiicker. Again adding a flicker filter should deal with it.

I haven't seen this happen on material from my GH1, got one commercial in broadcast right now - didn't notice any such flicker effects during editing. No promises though as I haven't intentionally looked for it.

Guess it's a slowly passing problem as more and more consumer displays don't do interlace anyway but shows everything in progressive. Thank god.
 
I'm not a pro, however the jiterring when panning is extremley noticable, but I wasn't filming with a tripod, and i was shaking all about,

however even when handheld, i was panning steadily a distant jet-ski, it was very clear,

so I guess you should just avoid panning quickly?

Is 720p much better to avoid this?
 
I agree with the rolling shutter and the CMOS difference. Has anyone shot on the RED camera, how bad is the effect there, since its the same kind of chip set-up ?
 
powervideo said:
It's not aliasing Barry. I'm definite on that. I'm sure it's a CMOS/rolling shutter related issue. I'm away on shoot but will post footage ASAP. I find it strange that besides Otis no-one else is seeing this. If most guys here are doing webvids, they may not be experiencing my observations. It's night and day to me. Maybe it's because I'm viewing on a broadcast monitor via HD-SDI, but it sure as hell doesn't look like 25P prgressive from Varicam or XDCAM HD.
Peter
Click to expand...

HI Peter,

have you done your tests ? Is there a place where we can see the footage and the results ?
THX
CiPO
 
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