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GH3 Bitrate & DR


Germy1979
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[quote name='HurtinMinorKey' timestamp='1346129336' post='16682']
I thought the reason the gh2 was so detalied was that it was a high bit-rate inter-frame codec? The 5d3 does more mbits than this for intra-frame and it gets blocky.
[/quote]

Panasonic developed the AVC Intra codec @ 100 mbps, 10-bit 4:2:2, broadcast standard. They are experts in making codecs efficient. The GH2s 24 mbps is VBR and mostly around 18 mbps, with which it equalled the 42 mbps of the 5DM2. That's why this sounds so promising.
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Yes indeed not all intra-frame high bitrate codecs are created equally, especially encoder chips. A lot of the mosquito noise on the 5D Mark III come from low contrast areas where the codec hasn't allocated enough data, or allocated it in the correct way.

Sony NEX is already better in that regard, with cleaner shadows too and the FS100 especially so. They are not even ALL-I 80Mbit but the engine and sophistication on display is vastly higher.
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No it doesn't all come down to just frame compression, it is how the compression is allocated within a frame, how motion in between i-frames in a long GOP codec is predicted with B and P frames, the quality of those 'synthetic' frames and a lot more very technical stuff.

If you look at the ALL-I frame compression, the 5D Mark III has less compression per frame than the FS100, but still the lows are gone. See what I mean?

[img]http://www.eoshd.com/wp-content/uploads/2012/04/5d3-vs-fs100-lows-660x312.jpg[/img]
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[quote name='HurtinMinorKey' timestamp='1346175189' post='16739']
So frame compression is all that matters (given a certain data constraint) for intra-frame compression( that what i was infering between posts #3-6).[/quote]

You assume that intra with AVC is the same as intra with DV. But it isn't. The frames exist independently, but the so-called [i]spatial prediction [/i]of AVC turned out to be more efficient in terms of reducing data rates whilst maintaining image quality than the temporal prediction, which needs variable bit rates to compensate for a lot of movement within a clip, ironically [i]then[/i] exceeding the intra frame data rates. So it can be argued, that unless you desperately need very low rates (sacrificing quality when motif and/or camera actually dare to [i]move[/i]), inter is inferior. No doubt it is perfect for web distribution or for amateurs who don't like to take a spare SD card for their summer holiday. Read the Panasonic [url="ftp://ftp.panasonic.com/pub/panasonic/drivers/PBTS/papers/WP_AVC-Intra.pdf"]pdf[/url] to AVCIntra (5 years old already!). There you can see, that there are 2 flavors: 50 mbps [color=#ff0000]10-bit[/color],[color=#ff0000] [/color]1440, 4:2:0 and 100 mbps 10-bit, 1920, 4:2:2. I know it's foolish, but I dream of 10-bit @ 72 mbps.

Someone wrote in a comment on 43rumors:

[quote][color=#444444][font=Verdana, Arial, Helvetica, sans-serif][size=2][background=rgb(250, 250, 250)]Yep, while heavy editing doing video professionals might hail AVC intra as second coming of Jesus for normal uses its just complete waste of space by needing to store same duplicate data over and over for every frame.[/background][/size][/font][/color][/quote]

As if there weren't enough mediocre camcorders for the video dads to choose from! Absurd! But alright, why did he buy a new computer if not to better cope with long GOP worms? Must pay off, no?

[quote name='HurtinMinorKey' timestamp='1346175189' post='16739']My point is that i'd rather see a higher bitrate inter codec on the gh3 than a high bitrate intra-codec.
[/quote]

But why?
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[quote name='Stephen de Vere' timestamp='1346232798' post='16775']
I can't find any reference on this site to the hope that the banding issue in GH2 will be resolved with the GH3. For me, unless that get's fixed every other improvement is pointless.

Am I missing something ?
[/quote]

Not at all bud:). Most of us are wondering ourselves. I hate the halos that emit from bright lights. I made a 4th of July vid and every firework looked like a nuclear missle launch. It's (gh2) - definitely got its issues regarding how it handles transitioning shades and such, but we never got the freedom to create our own color profiles either. I love cinestyle for my T2i, but i recently started using Visioncolor, and if you're pixel peeping, it Doesn't do the stairstep from one color to another. I'd assume it's the 8 bit space it has to work with. In After Effects, when I A/B 8 bit and 16 bit workspaces, i can see the banding in 8 bit. 16 bit doesn't do it. (granted, i transcode 5d to RGB 4:4:4 as well. You should try it if u don't already... And use Andrews gamma fix technique in Premiere with the Fast Color Corrector plug. full range input, 16-235 output... Double check that last number though.). Your shadows boost cleaner, and your highlights don't look like a supernova.

Personally man, Depending on how much they want for the GH3, if you're making movies primarily, i'd just save up a little more and grab the BMC instead? I only say that because you're much less likely to hit your head against the ceiling because of a lame colorspace, or a shitty codec, or whatever DSLR inherent issue you'd run into with a still's camera.

I can't believe i'm about to say this, but the Gh3's a "still's" camera first.... (I'm f--king banning myself from this site for that one.lol.). But who the hell takes pictures with a GH2 anyway..? Ha!

No doubt, the GH3 will be killer... But being completely redesigned, weathersealed, with an X series kit lens, (12-35 f2.8)... It's not going to be priced like a Gh2. People will easily drop $2000 for it if it's a killer, and it probably will be. If that's the case though, for a thousand more you can have a 12 bit camera with the option to shoot 220mbps pro res... And that's supposed to be the "lesser" codec! It's still 4 times higher than the GH3's. And i could almost guarantee the Gh3 won't be 4:4:4 12 bit raw.

But wtf do I know. Panasonic could've gotten wasted last weekend and said, "you know what f--kers?!.. Let's just go all out with this bastard. Yeah why not.. 4:4:4, 14 bit, RAW, clean HDMI out, 13 stops, X- series lens, unlimited lens options, $2000... Watch the world sh-t its pants.".

.....Only I would be that cool.
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[quote name='Germy1979' timestamp='1346235550' post='16777']
But wtf do I know. Panasonic could've gotten wasted last weekend and said, "you know what f--kers?!.. Let's just go all out with this bastard. Yeah why not.. 4:4:4, 14 bit, RAW, clean HDMI out, 13 stops, X- series lens, unlimited lens options, $2000... Watch the world sh-t its pants.". [/quote]
Laughed.

[quote name='Germy1979' timestamp='1346235550' post='16777']
.....Only I would be that cool.
[/quote]

Laughed out loud ;)

I still think even more people will start buying several bodies from now on. I for example want everything the BMC stands for, but with C300 like ergonomics.
I really see me buying a GH3, with at least some improvements over the GH2, just to do stuff the BMC is not as practical for. DSLR video is not over ;)
Also, IBC starts this week and Panasonic has to come up with sth to get talked about again.
So I wouldn´t rule out a AF200 (or even two new AF cameras).
It won´t come close to the BMC specs, but it should at least be able to top the FS100 and C100 somehow, considering it´s predecessor´s debut time...

I still hope Germy1979 is right and at least on Pana engineer got wasted, went to the lab and soldiered in that magic circuit board, lifting all limitations from the GH3´s hardware...
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I'm really looking forward to GH3! I never quite made the jump to GH2 from EOS, but my mind is still open, they have someone here they could sway, I hope they go all out and give Canon a good kicking for their complacency. I just hope they iron out the little bugs before releasing, like that banding issue and the high ISO horizontal band thing that looks pretty ugly...
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[quote name='jgharding' timestamp='1346681603' post='17223']
I'm really looking forward to GH3! I never quite made the jump to GH2 from EOS, but my mind is still open, they have someone here they could sway
[/quote]

I am in the same boat! I've got about $2500 saved up and i'm just waiting for photokina to see which company will get my money!
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I think they'd need to give me a lot of what Magic Lantern does but straight outta the box, such as histogram in video mode, good peaking, manual audio, possibly crop-marks for 2.35:1.

Intraframe codec with high bitrates would be brilliant, plus a good sensor that has some optimisation for video resolution. If they made it a 12.6 megapixel sensor that'd be 4K, which would be nice for scaling down to 1080. Or taking short 4K video clips for special composting and crop zoom shots.

It's also enough for good pictures really, but something tells me they'll make it a bit bigger than that for sales' sake.

A great EVF would be nice too.

I'd still never buy off a spec sheet though, I'd have to see the video! Every sensor and codec combo has such a different footage 'feel' these days. I can't wait to see some video!
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From 43rumors:

[size=3]
- 16 Megapixel “Wide dynamic range” CMOS Sensor.
- New Venus 7 engine
- electronic shutter
- ISO 100-12.800
- 6fps
- Fastest AF of any interchangeable lens system camera.
- Video Bitrate 50Mbps (72Mbps ALL-I)
- 30p/25p in MP4, MOV and AVCHD
- 3.5 Mic in
- built-in stereo mic
- Audio out
- Pc control
- Time Code
- 1740k OLED LVF, Touch Monitor OLED 610k.
- external battery grip
- Wifi with remote control through iOS and Android Applications
- external XLR accessory
- Focus Peaking
- Interval shooting and slow motion. Slow Movie extension (40%, 50%, 80%) Fast 160/ 200 / 300%
- Magnesium alloy body. Body is bigger than the [url="http://www.amazon.it/gp/search?ie=UTF8&keywords=Panasonic+GH2&index=aps&linkCode=ur2&camp=3370&creative=23322"]Panasonic GH2[/url].[/size]
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