Re: One Summer Evening with the FS700
 

Not controversial at all! And not just to do with H264 and AVC-HD. It's highly likely that with 1080p/25 and 1080p/50 the time difference between I frames is the same (1/2 second?) and hence the same difference between them because of movement.It follows that for 1080p/25 the GOP length is 12, for 1080p/50 it will be double that.

Since I frames need a lot more bits than difference frames, it's then easy to see that doubling the basic frame rate won't need anything like a doubling of bitrate. Practically, there's a lot more to it than that - the content differences between successive difference frames will be less (only 1/50sec apart, rather than 1/25 sec) so the coded size of each can be smaller with 50p than 25p. That will help compensate for the greater number of them.
Again, not unique to MPEG2. You need a certain minimum bitrate to get anything worthwhile at all, any increase then gets applied just to reducing deficiencies - and if they weren't that bad in the first place......

It's part and parcel of the same argumentabout the oft (mis)quoted statement about H264 offering half the bitrate of MPG2 for equivalent quality. It's true - but only at quite low bitrates. The H264 "tricks" do improve on areas where low bitrate MPEG2 shows problems. But improve the MPEG2 bitrate and there's less problems for H264 tricks to work on!

Hence H264 has big advantages or broadcast transmission and web video - less point for camera acquisition where bitrate is less of an issue.

Re: One Summer Evening with the FS700
 

You are correct Cees. The Shuttle 2 cannot do it. In BMD's press release they say it can, when in fact it can't.

Re: One Summer Evening with the FS700
 

To be clear, though, it sounds like we could record 240fps and still get 120fps frame decimated footage out to a non-3g recorder like the hyperdeck shuttle 2 or other device? This would be done by setting our recording format to 30p (since 60p requires 3g) and when writing out the buffer every other frame is still played out of hdmi/hd-sdi. Can someone confirm this?

Re: One Summer Evening with the FS700
 

As soon as my camera arrives I will test this idea.

Re: One Summer Evening with the FS700
 

Thanks for your input on Twixtor. Just wondering how the time limit on the FS-700 slo-mo works into a workflow with such a short burst. Making a clear choice between slo-mo or live might be difficult.

Re: One Summer Evening with the FS700
 

I think in most cases the time limit will be far more favorable to the work in post that twixtor requires. More likely you will find you rarely need up to the full limit since things you want to see in slow motion tend to happen quite quickly and you will want to keep down your buffer offload times.

Re: One Summer Evening with the FS700
 

I don't have the FS700 (yet), but Alister Chapman confirmed this on the same question when I asked it before. So the answer is yes.

Re: One Summer Evening with the FS700
 

These are not the only reasons to shoot high framerates.
Some organic movements are very hard to interpolate; the software just doesn't know how something like different hairs of a longhaired girl running towards the camera on a windy day move.
I tried this in december: most of the time it looks weird and fake. Only in one shot it was ok.
(And not thanks to Twixtor, but the standard options in AE.)

Or how thrown water splashed as it 'explodes' on a detailed object: it just yields distorted footage. (Which can be funny... lol)

Shooting high framerates wins in my opinion as well.