-
Key frames
If I’m editing on an HDV 1080i50 25 fps timebase, why when I export does FCP default to inserting key frames every 24 frames? Does this matter? Should they be every 25 frames? Or should I be selecting automatic instead? Or even all?
Thanks in advance -
4 Replies
-
Hi Neil,
You should avoid export through QT Conversion. You can not control nothing that way and everything is re-compressed.
In fact, unless you are printing to HDV tape, you should avoid rendering in HDV.
Rafael(and here some clips for the friends: https://www.vimeo.com/2694745 )
Some contents or functionalities here are not available due to your cookie preferences!This happens because the functionality/content marked as “Vimeo framework” uses cookies that you choosed to keep disabled. In order to view this content or use this functionality, please enable cookies: click here to open your cookie preferences.
-
Thanks Rafael,
Generally I use compressor but on the occasions when I’m exporting a low qual preview for a client or some such, I’ll just send it through conversion which got me wondering about the key frames thing.As to your other point about not rendering in HDV, can you explain a little further – will I get better results if I transcode to pro-res?
Cheers
-
[neil weaver] “As to your other point about not rendering in HDV, can you explain a little further – will I get better results if I transcode to pro-res? “
Hi Matt,
Is not a matter of transcoding.
Some people likes transcoding HDV or XDCAM to ProRess because they think it makes their editing easier due of the Intraframe nature of ProRess. HDV and XDCAM are more difficult to process. That is true if you have a low performance machine. I work with a MBP with XDCAM footage without need to transcode.
Also transcode means a generation lost unless you transcode to an uncompress codec.
If you just simply transcode HDV to ProRess, the only thing you do is to write an 8b/420 file as 10b/422.
Bigger file and the same picture.
If you transcode using an AJA thats other thing The AJA filter the Chroma improving the process 8b/420> 10b/422. The picture will look better this way.When you shoot HDV you should avoid o export/render to HDV, the same than when you work with DV you should avoid to render back to DV.
Those are too very compressed formats. Almost whatever thing that you can do in post to improve the look of the picture (CC, Chroma Smoothing) will be crunched again when you recompress.
Think of the postproduction like cooking.
When you cook something you add things to improve the taste of whatever you cook.
You need a recipient big enough to put all that.
In video the codec is more or less the recipient.
When you are for example color correcting you are generating new information.
In the DV “recipient” there is not room enough for all that you had added.
If you use a better codec you will be able to retain more of that
If you export back to DV you will loose a lot.
This doen’t means that because you may need to print bak to HDV or DV is not worth make CC. Not at all.
My recommendation is that what ever is the kind of footage you edit and whatever your final output format (Broadcast, DVD, Web,..) try to make a high quality master. From there you will be able to extract any version needed for any purpose.
rafael(and here some clips for the friends: https://www.vimeo.com/2694745 )
Some contents or functionalities here are not available due to your cookie preferences!This happens because the functionality/content marked as “Vimeo framework” uses cookies that you choosed to keep disabled. In order to view this content or use this functionality, please enable cookies: click here to open your cookie preferences.
-
Hi Rafael
Apologies for taking so long to reply to this post – new baby arrived 3 weeks early so had to drop everything and do some real work for a change!
Thanks for your answers – they’re real food for thought. One last question: what codec would you recommend for export in HDV?
Thanks again,
Neil
Reply to this Discussion! Login or Sign Up