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banding due to Interlaced film transfers indigital

Gavin Greenwalt
 

Usually “29.97” interlaced film scans are just 24 after a pulldown. Did they not just use an odd cadence?

 

Gavin Greenwalt

Seattle,WA

Charles Taylor
 

If it's 24fps film scanned at 29.97i, you should be able to reconstruct the original 24p frames without any fancy business. Do this before any re-sizing; it should be done on the raw scan, as untouched as possible. Rescaling or timewarping or retiming of any sort renders this much more difficult / impossible.

3:2 pulldown is a way of fitting a 24p/23.976p frame into a 30i/29.97i frame losslessly. It can be removed; most editing software should have a function for this. You just need to determine what cadence your clip is at (i.e., using the example from the wiki page here, https://en.wikipedia.org/wiki/Three-two_pull_down, does your clip start on A, B, C, or D?).

Once you've removed the pulldown correctly, you should have a 24p/23.976p clip that you can scale/retime as needed.

Charles A Taylor
Compositing Supervisor
Toronto

On Thu, Mar 15, 2018 at 11:28 AM Gavin Greenwalt <im.thatoneguy@...> wrote:

Usually “29.97” interlaced film scans are just 24 after a pulldown. Did they not just use an odd cadence?

 

Gavin Greenwalt

Seattle,WA