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Same here. Stephen can you fix that when you get a chance? Thanks |
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It was jerky for me too but i dropped it into power dvd and it played fine , try your dvd player. Andy. |
Say Stephen, I was wondering for trading in my HD101 for a 251 or 201, but what worries me is the image quality on 50p. As I understand it, the 50p compression with the new codec is also 'only' 19.7 Mbps - long GOP this time of course - ... How does that look compared to the picture quality of the HD101's 25p?
Does anyone know when you record 24p or 25p on the HD251 whether that is long GOP or short GOP? |
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Either if if the GOP structure is longer (12) or shorter (6), it's still the same fraction of time to the framerate it's applied to (ie 1/5 of a second). |
Yes, I did know that. What I meant to ask was: If you put the HD251 in 24p or 25p for recording, does it still encode in a 12-frame GOP, or is it then done on the 'old and reliable' 6-frame-GOP-way?
Furthermore. And this is something I'm worried about. Obviously it is still the same amount of time that's encode in 1 GOP, but it's TWICE the uncompressed data that needs to be compressed in that GOP (there are twice as many frames - the fact that it's the same time-interval is datarate-wise meaningless). Obviously, the longer the GOP, the more efficient the encoding (and the more profound the errors and drop-outs...), but doubling the number of pictures in the GOP won't make it twice as efficient, so overall, one would expect a degrading in quality. However I expect the quality to be about the same in the real world: due to the higher temporal rate the frames will have a smaller difference between them and they will have more defined edges, because of the shutter speed that'll be at least twice as high - both characteristics are making encoding easier and thus more efficient... |
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For me it's the example slo mo. I can only hear the music. The super_encoder file works fine.
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Stephen, since you tested the 250, can you comment on how much light it needs (shooting ay 50p - with a 100 shutter most likely)?
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Our comments were that it was cleaner than the HD-100 comparitavely. This is probably because the encoder is better and not to do with the lens (which was stock 16x) or CCD's (which are 1280x720 probably the same as HD-100). |
If it is the same, you should need more light to expose 50 frames in once second, instead of 'just' 25. But no remarkable difference there? You haven't tried it in a low light situation by any chance, I suppose?
I'm actually interested in upgrading from my 101E to a 200, which should be the 250 without the SDI, but my 101 already needs a lot of light for nice images - so shooting with the 200 at a double framerate and a double shutter speed scares me a bit... |
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When shooting 50p, your standard shutter speed will be 100 (or up - for me it'll mostly be 100). that's twice as fast as the standard shutter speed on the HD101, so There needs to be a difference in adequate light.
But, I did indeed forget that the camhead of the HD101 already works in 50p, so the amount of light will be the same as amount the hd101 needs with a shutter of 100..... |
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