GH2 official discussion thread

[Grunf]

this is why the 1080/50i in the GH1 was not an option because it really is 1080/25p. And that is not smooth.
Thanks

Not really. 1080i50 is NOT 1080p25. It has better temporal resolution, as each half-frame is 1/50th of the second. It's like taking a 1080p50 source and tossing every second line from each frame, while alternating odd and even lines for each frame.

Thus it's really like ordinary 50Hz PAL, except much higher resolution.

[mcsmooth]

Any idea if it was the 17mbs or 13mbs mode? Is this footage straight out of the camera untouched? Cheers.

It looks to be original footage, since you typically don't transcode to .mts. Bitrate avg is 16mbs, so would be 17mbps mode.

Unfortunately, it looks like the codec will probably be the same for non 24p native modes... no B frames in this file. This means that even if this camera did do 25p/30, the quality wouldn't compare to 24p due to the lower bitrate AND lack of B frames.

I think I'd rather have 720p60/50 available in the 24mbs encoding mode than 1080p30/25 (assuming we can't have 1080p60). On the other hand, it should be dead simple to implement 30/25p over 60/50i.

[mpgxsvcd]

I think I'd rather have 720p60/50 available in the 24mbs encoding mode than 1080p30/25 (assuming we can't have 1080p60). On the other hand, it should be dead simple to implement 30/25p over 60/50i.

1080p @ 60 FPS should be "dead simple" to implement as well since that is the sensor reads it. We know AVC-HD can support it. They already do it with their camcorders.

[blafarm]

Not really. 1080i50 is NOT 1080p25. It has better temporal resolution, as each half-frame is 1/50th of the second. It's like taking a 1080p50 source and tossing every second line from each frame, while alternating odd and even lines for each frame.

Thus it's really like ordinary 50Hz PAL, except much higher resolution.

I could be mistaken, but I think that is what he was saying..

[Bandido]

Even many of their managers have no idea about many technical sides :-)
And you are asking small representatives. They are good at answering common questions.
And they are usually 90-95% fo all questions (and about 100% with any press).

That is true. That has been my experience every time I go to the NAB convention.

You can see a lot of beautiful "expo models/actresses" talking about the product features. They have a strong stage presence and have excellent communication skills. They learn the script very well and show excitement when talking about the product. At the end of the presentation, they tell the audience to feel free to ask any question to the sale reps. Many of the sales people also learn a script so they send you to an engineer every time you throw a curb. Most of the time the engineers are the ones who worked developing the products, so they are very knowledgeable. The only problem is that sometimes their English is not very good. One time a was talking to a Sony engineer... Needless to say, it was funny to hear a highly technical conversation between a Spanish and a Japanese. It was in English, but we both had a strong accent.

[Rolf Silber]

Not really. 1080i50 is NOT 1080p25. It has better temporal resolution, as each half-frame is 1/50th of the second. It's like taking a 1080p50 source and tossing every second line from each frame, while alternating odd and even lines for each frame.

Thus it's really like ordinary 50Hz PAL, except much higher resolution.

I am distinctively befuddled, why they have no 1080 25p but only 24 p now. If this mode gives me more "cinematic pictures" I beg to aks, why I can't have 25 p "cinmatic pictures" any more all of a sudden.

I shoot 1080 25 p with my GH13 - so what should I do in the future when I want to mix material? What happens if I shoot in 24 p? Why did they do that? Strange. Any explanation is welcome.

[Arnarfjodur]

Auto focus video (sorry if this link is not the first time here, hard to follow 45 pages...)

http://www.youtube.com/watch?v=k2eBL...layer_embedded

With a fast autofocus, and a touch screen focus interface, do you guys think this will be a viable option for rack focusing or say, follow a walking person with the focus, without the need of a dedicated focus puller and a follow focus unit?

[marcram]

I am distinctively befuddled, why they have no 1080 25p but only 24 p now. If this mode gives me more "cinematic pictures" I beg to aks, why I can't have 25 p "cinmatic pictures" any more all of a sudden.

I shoot 1080 25 p with my GH13 - so what should I do in the future when I want to mix material? What happens if I shoot in 24 p? Why did they do that? Strange. Any explanation is welcome.

I believe the 25p in 50i wrapper is solved by shooting at exposures less than 50 Hz as previously discussed.

Likewise, we should be able to get 30p in a 60i wrapper by shooting less than 60 Hz. Two consecutive fields will be acquired from the same temporal exposure.

[marcram]

I am very excited about the 1:1 crop video mode. As a suggestion for a future full-frame camera, let the 1:1 pixel map be 1080/2k/4k sized image circle of the m43 and let bigger full-frame lenses cover the full extent of the larger sensor. This would drastically improve high ISO performance and eliminate aliasing and moire. I really wonder how the downsampling is being performed in the GH2. Is the processor using pixel binning in the non crop video mode?

[kainekainekaine]

Anyone know if the 1:1 mode would be better suited than the none 1:1 mode for chroma keying due to less problems like aliasing/moire etc?