flicker lines in 24pa

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dmitriandsnow

Well-known member
Hey guys,
Just finished shooting captured it all into post, everything is the way i want it to except this one glitch. When viewing the footage what seems like interlaced flicker lines appear on the borders of black and white. This flicker-like effect jumps up significantly when the camera is still. When moving the motion blur gets rid of the this mess. I shot this under fluorescent "full spectrum" 93CRI 5500K 2500 lumen bulbs.
Used the Fluo matrix with cine-like gamma. I am not exactly sure what other info might be needed but these flickers are something i can not stand. I thought this could be the stutter of the 24fps rate but this contradicts the fact that flicker seems to disappear upon the movement... Sheesh i am out of it.
Help please!!! Thank you.  


Oh i am in Vegas by the way.
 
Re: flicker lines in 24pa

Is it thin-line twitter, caused by shooting in THIN and then playing back on a television? That would behave the way you're describing.

Or is it "comb" artifacting that happens on vertical lines, on the transition between black and white?
 
Re: flicker lines in 24pa

It is something you get after rendering as Widescreen DV (2:3:3:2) pulldown added.  Captured as an uncompressed dv with 2:3:3:2 pulldown removed would yield 24fps. When same pulldown is added shouldn't it go back to ntsc 29.976?
Well the remedy to this is to render as uncompressed dv no pulldown added. Just makes little sense since pulldown should take it back to the original.
 
Re: flicker lines in 24pa

(minor point for clarification): There is no 29.976, there's 29.97 and there's 23.976, so I'm not sure which one you meant.

When you render a 24P project as one of the templates with pulldown added, the file retains its 24P nature so you can re-import it and edit it as 24P.

If you render as one of the templates that doesn't add pulldown (NTSC DV or Widescreen NTSC DV, for example) then pulldown will STILL be added, but the 24P flags won't, so the file will now act like a 29.97 DV file that you can't (easily) remove the pulldown from to reconstitute the 24P frames.
 
Re: flicker lines in 24pa

Clarification appreciated, Thank you.
To summorize i tried adding the advanced pulldown to 24fps footage and that is what caused the awful flicker. Oh one thing, raw material directly from the tape(29.97fps) was also flickering when viewed in media player.
Does all 24pa footage act in such way without the pulldown removed?
Very cool.
 
Re: flicker lines in 24pa

I don't know what you mean by flicker though. Are you talking about the interlaced split frame that happens on one out of five frames?
 
Re: flicker lines in 24pa

I am assuming that is so, because when i viewed the raw capture files they play back 29.97fps with the flicker.
Once the pulldown is removed and rendered as an uncompressed avi 24fps everything is fine.
 
Re: flicker lines in 24pa

I may be wrong but I believe that fluorescent lights flicker so that may be what you are seeing (maybe 24pa exacerbates this problem?)
 
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