GH2 official discussion thread

Vitaliy Kiselev said:
Get any camcorder with 50i and compare.
Motion is more fluid, but original progressive frame restoration is impossible.



It has one simple limitation - sensor resolution.
Your focal multiplier will be 2x2,6=5.2
And that is all.
Bunch of cheap 2/3" glass prices will skyrocket in 2011.
So, make investments.
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Thanks!
 
Vitaliy Kiselev said:
SO, after carefull reading this http://panasonic.net/avc/lumix/systemcamera/gms/gh2/movie.html

Here are my conclusions:
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Digital Zoom is independant function from EX. OPTICAL ZOOM
Ex. Tele Conv is indeed 1:1 mode. It is HUGE!
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This will make my 16mm lenses happy, and happy lenses make better pictures.
 
lpowell said:
No, it's a bad idea. A 50i video stream has only half as much data as a 50p video stream contains. What typically happens is that half of the horizontal scan lines in each 50p frame are discarded...
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Thanks, but I was comparing 50i from 50p to 50i from 25p, not 50i to 50p.
 
mcsmooth said:
Note that the *2 comes after the 60i talk. The next sentence separately talks about the 24p native mode, which sounds promising.
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I think you are right, because according to global product page that Vitaliy linked to the Cinema Mode sure does look to have the native 24p output. Oh, boy, I can almost taste the pudding. Please someone get us some MTS!!!

avchd.gif
 
divide said:
stockfuel: frame burst is 4k on GH2, not 1080p.
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At 16:9 it records to 2mpx.... at 4:3 it records to 4mpx (according to the official Pana site)

But Vitaliy is right..... going from 18mpx on 4/3" to 2mpx is a big difference to the Casio. I was just praying for maybe 10 seconds, for my work... it would be perfect.

Speaking of which... Vitaliy, if you can hack that mode and get me 300 frames.... i'll give you $1000... seriously. Same goes if you can hack the EX-F1.
 
stockfuel
I am Russian as Vitaly - can hold secret talks (just kidding) and suddenly "?
Once done updating the firmware - I think Vitali will be able to help not only to you. but it will not happen before December
 
mcsmooth said:
I'm not sold on B-Frames yet... an HMC at 17mbps performs much better than 20% over an I/P implementation.

20% could simply be the 17 to 24mbps bump.

...or if it is 24p native, they could just be accounting for the fact that 24 frames is 20% off of 30 (60i), or that progressive frames are more efficient than interlaced.


I haven't seen that anywhere, but it sure would help if it's there.



I'm not seeing hard evidence yet, but does seem possible since there it uses a new mode with it's own bitrate. The slow/fast motion modes they would be pretty annoying interlaced, but then again, so is everything interlaced.


It takes a ton of power just to play back HMC files let alone encode them, so I don't think we are going to see the same implementation or they would be bragging about it. I hope I'm wrong, but it seems unlikely with those numbers.

Regardless, there are some great improvements to make it that much better. It's never going to quite a full AF-100, but should give very similar picture quality at a fraction of the cost. Best of all (for the consumer and Pany), one can always upgrade from the GH2 (or other m43 cam) to the AF-100 (or rent) and have their lens collection ready to go.
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Ummm...the evidence for B-frames would be that they said on their powerpoint that they gave 20% better quality by using compression that looks at the next frame and the previous frame...they even showed a diagram. That is the textbook definition of a B-frame...it has nothing to do with things not being interlaced...which also will further raise the quality.

As for the power required, there's a reason they stuck a whole extra processor in this sucker.
 
Right, this camera looks awesome but confusing. I get that it can do 24fps natively now, but for my course, they want work in 25fps, if I recorded in the full HD 50(i/p?) mode, can I get 25fps footage out of that? it's a bit of a drag, but I don't mind the deinterlacing/pulldown process, aslong as I can get 25fps. Im in PAL territory aswell. Thanks all
 
himynameisnathan said:
Right, this camera looks awesome but confusing. I get that it can do 24fps natively now, but for my course, they want work in 25fps, if I recorded in the full HD 50(i/p?) mode, can I get 25fps footage out of that? it's a bit of a drag, but I don't mind the deinterlacing/pulldown process, aslong as I can get 25fps. Im in PAL territory aswell. Thanks all
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Aren't 50i and 50p both very easily converted to 25p? Just deinterlace the 1080/50i or drop the 720/50p into a 25p timeline in your NLE.
 
himynameisnathan said:
Right, this camera looks awesome but confusing. I get that it can do 24fps natively now, but for my course, they want work in 25fps, if I recorded in the full HD 50(i/p?) mode, can I get 25fps footage out of that? it's a bit of a drag, but I don't mind the deinterlacing/pulldown process, aslong as I can get 25fps. Im in PAL territory aswell. Thanks all
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Nathan, typically, it is possible to remove 2:2 pulldown from interlaced footage that was originally progressive without loss of resolution. So, unless some unusual implementation has taken place, it will be possible to get 1080p at either 25 or 30 fps after removing pulldown.
 
I met Philip Bloom last week in Los Angeles. He shot the GH-1 for Panasonic before it was released see his film Joshua Tree on Vimeo. That was obviosly the prehacked version and looked great. He told me Panasonic, the same guy that hired him for the GH-1 called him to test a new camera, He didn't specify the GH-2. So he will be shooting a film with it soon. I will ask him for his hands on opinion. He has a blog so keep an eye when he posts the video.
 
Cheers Ben and Svecher, that's what I thought, just wanted some clarification about it. Can FCP or AE de-interlace the footage or are other programs needed. Last thing, sorry. Apparently the sensor is actually capturing 50/60 progressive frames but interlacing them due to AVCHD, is this true, and would a hack be able to remedy this?
Once again, thanks
 
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If there was an option to select the framerate in 40fps continuous shooting mode (like 25fps etc), it would be a dream camera.... no more problems with codecs, aliasing, low resolution (as far as the Canon DSLRs, anyway) etc etc. It would be EXTREMELY high quality. :laugh: It clearly has the potential, seeing as it can do 40fps alraedy...


himynameisnathan said:
Apparently the sensor is actually capturing 50/60 progressive frames but interlacing them due to AVCHD, is this true, and would a hack be able to remedy this?
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The camera records in 1080i60 (also sometimes called 30i). The GH1 recorded in 24pf/25pf (basically, progressive frames stored in 60i, and 50i respectively). There's NO WAY to get true 60p from 60i, and there seems to be quite a lot of confusion about the matter (probably stemming from 43rumours), and to get 30p from 60i means loosing HALF the vertical resolution, making HD not actually HD at all.
 
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Ex tele conv mode and noise

Ex tele conv mode and noise

This new digital zoom that uses only the center area of the sensor sounds excellent. It makes my 300mm Nikkor with 1.4x teleconverter to 2200mm (35mm equivalent) in 1080 mode and to 3300mm in 720 mode. And with full resolution!

The 14Mpixel resolution for 16:9 aspect ratio for the photos is 4976x2800. When only 1080 pixels are used, the vertical zoom is 2800/1080=2.59. If 720 pixels are used, the vertical zoom is 2800/720=3.89.

The noise will be a big problem since only a small portion of the sensor area is used: 1/(2.59*2.59)=1/6.78 part in 1080 mode and 1/(3.89*3.89)=1/15 part in 720 mode. If the noise is tolerable, say at ISO 1600 without this zoom, the same noise would be expected with this zoom at ISO 230 (=1600/6.78) in 1080 mode, and ISO 110 (=1600/15) in 720 mode.
 
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