back to the basics...

*sigh* - i thought i'm past this stage, but here it goes.

i transcoded a DVD track to prores with MPEG streamclip and dropped it in my browser and from there into my timeline. FCP asks its thing and i say, yes, adjust the sequence settings.

now when i add *anything*, like a fade or text bit for example, the timelines becomes red at that point requiring rendering. this is a single clip on the timeline. above the rest of the clip the timeline is grey.

why do i need to render??

sequence settings now say:
768x576 (CCIR 601 PAL Sq (4:3))
Aspect: Square
Field dom: none
Timebase 25
Compressor: Prores 422

thanks,
stefan

--
macpro 2x3 ghz dual core intel, 10.6.8, FCS 2

Your sequence should be 720x576, so should your footage. The clip was resized in Mpeg Streamclip.



www.strypesinpost.com

MPEG Streamclip was naughty for changing the 720x576 unsquare pixelled original to 768x576 square pixels. But why is FCP7 being naughty about requiring extensive rendering of the latter? Why isn't a 768x576 square pixelled ProRes clip as valid as a 720x576 unsquare pixelled ProRes clip?

I verified stefangs' finding. When the anti-alias filter is applied to the 720x576 clip at amount 2, FCP7 shows the green line -- preview possible without render. But when the amount is increased to 3, FCP7 shows a red line. (This threshold may be due to my system capabilities.) When the anti-alias filter is applied to the 768x576 clip at amount 0, FCP7 already shows the red line. That's absurd since amount 0 means no calculation. As stefangs said, adding *anything* to the 768x576 clip provokes the render demand.

FCP7 allows resolutions not in the shortlist but then flounders with them. Does FCPX do better with this?

Dennis Couzin
Berlin, Germany

FCP has bad real time performance with formats and frame sizes not blessed by the RT Extreme engine.



www.strypesinpost.com

I have the solution, but you may not like it.

We encounter this on virtually every mpeg based project including any flavor of XDCAM.

There are several options.

1 - transcode everything to pro-res before editing...and edit a pro-res timeline

2 - keep your native XDCAM format (or other mpeg based) and have your timeline render everything in Pro-Res

3 - and this is what works for us but it's time consuming and creates enormous files - export from your timeline to ANIMATION codec.....then take that into DVD Studio Pro - that virtually eliminates the sawtoothing.

We have non of this problem with DVCPRO-HD - only various versions of HDV (yes XDCAM is just hdv on steroids)

There will be graphics that may be a problem with fine lines that you may need to blur a bit in photoshop

There may be scenes with high contrast and fast camera movment that won't compress well - I suggest adding compression markers -- or try deinterlacing just that scene before rendering out


All of this works for us after long trial and error