GH2 Ipowell where are You?
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Thanks for the shout out, but like everyone else, I'm just starting to experiment with the newest GH2 hack and discover how it works! Compared to the GH1 hack, however, there are even more opportunities for improvement of the GH2 and I'm eagerly looking forward to exploring them.
Probably rather the opposite. GH2 utilized the codec better, GH1 was flawed on purpose. Either way, I'd find it very odd if GH2 suddenly "blew away" GH13 (well, guess some/most would say it already does, for whatever it's worth... GH13 image detail is superior GH2 if used properly -- no discussion)
edit: unhacked GH2<->GH13, obviously (less food for trolls quoting...)
edit: unhacked GH2<->GH13, obviously (less food for trolls quoting...)
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John Caballero
Veteran
It is common sense that the GH2 would be an improved version over the GH1 or GH13. Just common sense.
Huge progress was just made. We now have completely stable 32 mb/sec video. With B-Frames you really don't see as much improvement with really high bit rates. This is basically Blu-ray quality or better in camera.
http://www.personal-view.com/talks/discussion/414/ptool-3.61d-topic/p2
http://www.personal-view.com/talks/discussion/414/ptool-3.61d-topic/p2
Uwe Lansing
Veteran
Thanks mpgxsvcd for all your effort! But I just did a bit of pixel peeping (200%-forgive me). I don´t see any big difference except that the higher bitrate shows more noise. But I know it´s just the beginning of testing...
plasmasmp
Well-known member
It shows a bit more noise in motionless scenes, but objects in motion where the big difference lies. Essentially bumping up to 42-50mb removes all macroblocking from objects in motion. This is huge. For the first time the hacked GH2 beats the hacked gh1 in every category.
I think you all might have unrealistic expectations. The bit rate of the GH2 24 FPS was already much better than a stock GH1. There simply wasn't much room to improve on it. However, 720p and 1080i were much closer to stock GH1. That is where the hack will help.
Now the difference is probably not what you are expecting. It isn't going to add resolution and it isn't going to change the way the picture looks. It will eliminate all compression artifacts and increase the fidelity of the noise which is desirable to some people.
The GH2 is a perfect camera for most users. It really doesn't need the hack for home use. All benefit from the hack is completely wiped away if you re-encode at all. However, for those people who are cutting and editing with an NLE they probably will see some benefit in very detailed scenes.
Noise from the chip is where all the bitrate goes into
Thus, even if chip is noisy, GH2 high-bitrate codec will try to encode it and show it to you. Garbage in, garbage out. With GH1, you wouldn't get the noise but muddy patches.
Uwe Lansing
Veteran
It might well be so. I´m just a rookie with all that hack stuff and I didn´t own a GH1(3). But if I´m not mistaken I´ve read some things about IQ improvements with a hack along the way. But Ok, let me resume shortly what you´re trying to say to me:
- there will be no better IQ in static shots? The image wont show more details?
- compression artifacts like mud in 720p will be most likely eliminated - mainly in shots with motion?
- higher bitrates will show more noise. Like Grunf mentioned "garbage in, garbage out"?
Is that right?
Ian-T
Veteran
It’s pretty much what most of us expected (and wanted). Static shots were already sharp. It’s that little bit of mud in motion that we want to get rid of (which apparently is gone). Not only will a higher bitrate help the compression artifacts in 720p but also 1080p when it comes to shadow detail. When it comes to the GH-1 (and basically most CMOS cameras...not only DSLRs) I’ve always hated the murkiness/muddy-look in the shadow areas especially in green colored leaves in trees etc. The fact that the image now looks noisier after this hack on the GH-2 means it is allowing or squeezing all of the detail it can get out of the image. Now...we have control over what we want to do with it and not leaving it up to the camera to decide internally. I remember commenting on the noise and shadow detail from some Ninja footage. If we can do that without having to buy an external HDMI recorder...then it’s gravy from here.
Another benefit I see is...less macro blocking. In Vegas, when it comes to highly compressed images (without looking at the actual image), I can see macro blocking on the scopes. The less compressed these images become the less I see macro blocking on the scopes. It will also help color correcting big time. You will be able to push the colors a little more. I’m not sure yet if 42Mbps is a significant change...but the more the merrier.
EDIT: I'd much rather noise from the sensor than compression artifacts any day.
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Uwe Lansing
Veteran
Thanks Ian for the clarification! Now I´m a bit smarter in that department. - And it´s just the first day after the new Ptool release - maybe we´ll see some little more improvements in the next couple of days...
No, I do not agree with your statements.
1. Static shots with extremely detailed scenes will show an improvement with 720p and 1080i and perhaps 1080p @ 24 FPS. However, that is true that it won't show more detail. Detail and compression artifacts are two totally different things. We are trying to eliminate the compression artifacts by using the hack. The settings I am currently using will do that.
2. Mud is eliminated in pretty much every shot for every format with the latest GH2 hack.The only exception might be in some crazy detailed test shot with a propeller spinning very quickly. There isn't much that would get the camera to handle that.
3. Higher bit rates will render noise more precisely instead of smoothing it out. Some people consider smearing out the noise to be akin to throwing your dinner in the garbage before you even try it. Noise isn't always undesirable.
Stevet
Veteran
Thanks Ian. I couldn't agree more!
Will the new hack improve issues of color banding in blue sky shots, as seen here: http://www.dvxuser.com/V6/showthrea...olor-banding-in-the-sky&highlight=sun+banding ?
Ian-T
Veteran
It's said that this kind of artifacting is iherent with 8bit color sampling. It has a difficult time transitioning from one color to the next. That makes sense. But, I'm inclined to believe that it will help in some way but not "necessarily" as much as we want it to. How do I think it will help? Well, if you look at those artifacts you can see macroblocking issues in every transition (from lighter to darker etc.). Well, if a higher bandwith helps with macroblocks already then I would expect images like those to transition a lot smoother (IMHO). But...let's wait and see.
EDIT: I just though tof something else. One method folks used for many years to combat artifacts like the above is dithering.....which is basically adding some noise to the image in post. Well...now that we have a higher bandwith....which allows the "native noise" to come through...I'm hoping they add up to less color banding.
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Where 8-bit color depth gets coarse is with smooth gradients in dimly lit areas. Most of the 8-bit numerical range is devoted to representing bright shades, leaving 4 bits or less available (i.e. 16 steps) for encoding dark shades. As Ian-T points out, a bit of dithering in the shadows could help conceal the banding caused by coarse color resolution.
