Set different Edit Timebase and Display format

[Peter Sinter]

As editing 50p in an interlaced timelime created some issues on playback in the viewer window I would prefer to work in 50p and finalize in a 25i timeline.

If I copy my 50 timeline over in the end to a new one in 25i audio is out of sync as video sometimes gets shifted by one frame.

This is to be expected as premiere has to copy from a 50 frames editing timebase to a 25 frames editing timebase.

(Although it would be possible to move audio accordingly as audio files dont have to move on a frame basis)

Now on creation of a sequence I see that I can select a different editing timebase than playback timebase so it would be perfect to edit in a 25 frame timebase but play back the video in full 50p.

But as soon as I select 25 frames editing I dont have the option to select 50p playback anymore. 

Is this possible?

[Mike Dziennik]

What format is your footage? What 'issues' are you experiencing in the 'viewer window' (I presume you mean the source monitor...or the Program monitor...or both?)

If you cut 25i footage (aka 50i) in a 25i sequence, then export it as 50p...you will get each field deinterlaced and mapped to the 50fps so you will not get duplicate frames. Is this what you want?
It's not clear what format your source is, and what you are trying to deliver?

[Peter Sinter]

Thanks for your help and sorry for beiong not clear enough.

I am editing 50p UHD footage into a 25i timeline as I have to deliver XDCAMHD 25i for Broadcast.

But I am not able to see interlaced in the viewer window - it doesnt support interlacing.

Plus there are some bugs with the premiere plugin from Blackmagic for the Ultrastudio monitor 3g, so playback gets stuck sometime when the footage format differs from the timeline and it has to interlace on playout.

So I wanted to edit 50p in a 50p timeline and then AS A LAST STEP - copy it to 25i to be able to see and fix aliasing moiree if it occurs in the interlaced timeline and export directly to XDCAM.

BUT therefore I need to edit on a 25p timebase, so the video or audio will not shift when I copy it over.

[Mike Dziennik · Accepted solution]

The shift you are seeing when copying into a 25 timeline may be because premiere will use the nearest 'even' numbered frame. Eg. in a 50fps timeline, if the first frame of a clip is 00:00:00:03, then when you put that clip in a 25fps timeline it will round to an even numbered frame (00:00:00:02). Once you put the clip on an interaced 25fps timeline you should see both the frames interlaced together (00:00:00:02 + 00:00:00:03). You will need to enable "Display both fields" from the wrench menu next to the Program monitor to see the fields on your computer screen. The fields shown on your external video monitor will be determined by your blackmagic settings.

[Peter Sinter]

Perfect!! Its so easy!! I didnt know about the setting "display both fields", great! Now I can work natively in an interlaced timeline and dont need workarounds! Thanks a lit Mike!