GH2 in Europe: 25PsF, or not?

Well, as I think we've established, it's a very sketchy way of doing 25p. But to achieve this, you need to shoot in 1080/50i mode, which is limited to 17Mbps bitrate. StreamParser does show that it has B Frames, so I'm led to believe that this 17Mbps should be better than the previous incarnation of 17Mbps.
 
Of course. However, what I am interested in is what happens when shutter speed becomes slower than 1/60s (or 1/50 for PAL camcorder). TRV900, for example, gives progressive picture but with 1/2 vertical resolution (so one field is stretched vertically). GrahamH??
 
My guess is that it is half-resolution. If we take an extreme example of, say, a 1/4 second exposure, I assume the sensor is read into a buffer for that duration, and then the buffered data is sent out repeatedly to 16 successive fields. Meanwhile the buffer refills and cycle repeats.
 
I wonder if Panasonic engineered it to store frames as ab bc cd etc., instead of aa bb cc dd.. :|
 
That behaviour seems to alter depending on the shutter speed. Of the two samples posted on this forum, one ("00080.MTS") is derived from 25p frames and can be recovered, if you feel that running all your work through am AVIsynth script is something you can live with. The other ("000079.MTS") is true 50i and there is no way of recovering true 25p from it. I got the impression from what was said that the camera produced the former behaviour when the shutter speed was 1/40s or slower.

Either way, the bitrate is not enough for 1080p - unless there's something terribly wrong I'm not seeing, it really doesn't look that good as either interlaced or progressive. Both files I have encode a combined bitrate for both video and audio of under 16Mbps.
 
Phil Rhodes said:
Either way, the bitrate is not enough for 1080p - unless there's something terribly wrong I'm not seeing, it really doesn't look that good as either interlaced or progressive. Both files I have encode a combined bitrate for both video and audio of under 16Mbps.
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You have to remember, that the crude testing I did was shot at ISO 3200 in very uncontrasty conditions with a scene lacking in detail. So there's very little to write home about. I'd suspect a scene with more detail recorded at lower ISOs would return tonnes more detail, even in the 17Mbps bitrate.
 
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