TM900-Should I record in iFrame?

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TM900-Should I record in iFrame?

I'm picking up a Panasonic TM900 camcorder in a few days to replace my current HDV cam. I am looking forward to the file based workflow and to someday, shooting in 60p.

The TM900 supports Apple's iFrame and I'm wondering if, for now, I should use that setting.

I'm on a 2.16GHz C2D iMac (last of the white ones). I have 3GB RAM. I will be editing in iMovie. I'm thinking this machine will struggle--or not work at all--with 1080 60p.

My shooting is 70% family videos and 30% short films for fun. Distribution will be YouTube/Vimeo, Apple TV 2 and some DVD.

I just hate to "waste" all that resolution at record time by moving down to iFrame. But, if that is all I will be consuming for the next few years, it may make sense.

Just wondering what you all are thinking? Does iFrame have a place? Or should we always capture at highest and spend the time in post to down convert for editing?

20" iMac Intel Core 2 Duo 2.16Ghz, Mac OS X (10.4.8), 2GB RAM/250GB/SuperDrive

Posted on Jul 13, 2011 7:35 AM

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Answer 1

elikness

Level 4

2,640 points

Jul 29, 2011 6:00 PM in response to Brian Andrews

I think this is very good idea, it's going to conserve disk space and it's going to play fast in iMovie too. I've purchased the HM-T1A (Flip style) from Panasonic for the very reason that it records direct to iFrame. The reason I did this was for the sake absolute flat out speed. I don't want to convert, transcode, or wait one second to import ANYTHING into iMovie. Similarly the issues presented by up and down conversion of 720p or 1080i footage means you're always expanding to the full rez, then down-rezzing to get it into the Apple AIC format to edit in iMovie. With iFrame it comes right in, never gets touched. And it actually captures more rez believe it or not. Hows that possible you ask? Well, the iFrame format compresses each frame a lot less than typical HD formats, and it doesn't cheat by skipping frames the way the HD formatted clips do. You will find the Data Rate for each size/rez tells it all. On my HM-T1A the data rate for iFrame = 25-26Mbits/sec. All the higher rez 1080i and 720p formats have much lower data rates 17-12Mbits. The reason is the H.264 encoding and MPEG-4 skip frames and use math to re-generate them when played back. When you import that footage, your Mac more or less is re-recording those reconstituted re-inflated video frames at the iFrame rez of 960x540. While others will argue with me, I would argue in return if you're compressing a single video frame a factor of 12:1 or 17:1 there's no free lunch, it's not really HD it's heavily compressed HD. The iFrame actually records each and EVERY frame of video at 30frames/sec. Compresses within those frames and that's what you get in iMovie. No re-generated, re-constituted, re-inflated mathematical algorithms giving you back all the pixels it estimated and threw away. For me iFrame is good enough, it's higher fidelity and FAST, FAST, FAST to get started editing as soon as I import it into an Event.

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