GH2 GH2 hack a placebo?

This is one of the best tests I have ever seen. It is very precise and very accurate. What it really shows is that it is up to the user to make the most out of the hack. If you are shooting normal scenes like what was done in this test you will be hard pressed to see a difference between 24 mb/sec and much higher bit rates.

However, if you are shooting scenes with excessive noise or scenes where the entire frame is in motion(Like what LPowell is describing) then the hack can become essential.

You have to strike a balance between reliability and necessary bit rate. There is no one right answer. It is up to the person to decide when and what hack to use. In most cases using multiple hacks will give you the highest quality and most reliable footage.

There were parts of the footage where I swore that the hack was clearly better. However, there were other parts where I would swear the unhacked footage was as good or in a few cases better.

That just shows that in normal scenes the hack is not always beneficial. Since I shoot mostly normal scenes that require 100% reliability I choose to use the most stable hack there is.
 
Bassman2003 said:
It is very simple...More information is always better. AVCHD at the "normal" bitrates is pretty restrictive. The bare minimum to get a decent image imho. I prefer not to do anything at the bare minimum so the hack gives one the opportunity to move the GH2 out of the that category.

Frustrating to me how camera makers and some shooters want to limit the information recorded saying we don't need it. Well if we don't need why do the folks who make the "big" movies want/need it? - Because more information is always better.
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It is not that we don’t need it. It is simply that in order to shoot with these hacks you must buy an expensive card/cards to shoot reliably. If there weren’t any reliability issues at all we would use the highest bit rate we possibly could every time.

Until that happens your best bet it to use the highest quality hack your cards can reliably sustain.
 
lpowell said:
Actually, my tests indicate that it's quite risky to use an unhacked GH2 for any shot that may overtax its restricted bitrate. With stock firmware, the GH2 may plunge into a low-quality Fallback Mode in situations where it cannot handle the amount of image detail required. The hazard is that when the unhacked GH2 fails, it does so surreptitiously without alerting you to the fact that it recorded degraded, low-quality footage.
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Let me preface this with the fact that I think Lpowell’s latest settings are the highest quality with an extreme bit rate that I have seen. With that being said they are not stable with class 10 cards for all modes.

I just downloaded the patch file that Lpowell suggested a few posts before(Flowmotion Version 2.2 if there is a newer one please let me know) and got the write errors in both 720p High and 720p Low in less than 1 minute of shooting without ETC on a Class 10 30 mb/sec Sandisk card with the 14-140mm.

The settings work perfectly on 1080p @ 24 FPS. They are rock solid, produce wonderful results in the extremely complex high motion scenes, and never fail. However, the 720p settings are simply too aggressive.

I only say this because I think his settings are excellent. I hope one day he decides to back off on the 720p GOP setting. That is what causes the write errors when shooting video in full auto mode(AKA Stills mode).

Lpowell,

If you want to know the specifics on how it failed I can post those wherever you want. I do want to commend you on the settings. I just think the 720p settings could use a little tweaking that won’t affect quality drastically but will improve reliability. Keep up the great work.
 
mpgxsvcd said:
The {Flow Motion v2.02] settings work perfectly on 1080p @ 24 FPS. They are rock solid, produce wonderful results in the extremely complex high motion scenes, and never fail. However, the 720p settings are simply too aggressive.

I only say this because I think his settings are excellent. I hope one day he decides to back off on the 720p GOP setting. That is what causes the write errors when shooting video in full auto mode(AKA Stills mode).
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Thanks for your praise and work in testing Flow Motion v2. In response to your findings and others', I conducted a number of tests using the GH2's consumer-friendly auto-exposure features with Lumix auto-focus OIS lenses, including the motorized zoom features of the Lumix 45-175mm lens. What I concluded is that the use of these automated features at the camera's highest frame rates in 720p SH mode can in demanding conditions, overload the camera's processor with more work than it can handle. In those circumstances, I recommend using Flow Motion's 720p H mode, which operates exactly the same as 720p SH mode, but with its peak bitrate safely limited to 60Mbps. I've also updated the Flow Motion v2.02 documentation with details on the GH2's automated exposure features that can be problematic in this manner.

The reason I chose not to reduce the 100Mbps bitrate of the 720p SH mode in Flow Motion v2 is because that would also lower the bitrate of the 1080p HBR and FSH modes as well. Just as you've found with FM2's 24p modes, 1080p HBR and FSH modes work reliably at 100Mbps with the full range of lenses and auto-exposure features the GH2 offers. Since many shooters use 720p modes with manual-focus lenses in manual exposure mode, I felt that a better solution was to optimize 720p SH mode for that purpose, and support the GH2's automated features with 720p H mode.
 
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I understand. What about limiting the H mode to about 28 megabits per second average? That way you can program one of the c1, c2, c3 modes to act as a stills mode with auto video. Then when you want to use the higher bit rate you can just use the normal SH mode.

Both H and SH modes failed in under a minute. SH failed in about 25 seconds and H failed in about 48 seconds. I just thought it would be worthwhile to make the "H" mode the true fail-safe mode. Where the bit rate was high enough for all normal shooting scenarios but not so high that it becomes unstable in those normal scenarios. If someone always wants the absolute best quality then they still have the SH and HBR modes as they are today.

Just a thought.
 
The 60Mbps peak bitrate of FM2's H mode is actually quite moderate for the GH2, and I doubt I could confirm that setting a lower peak bitrate would improve its reliability in 720p mode. In my testing, I have been unable to provoke any recording failures in 60Mbps H or FH modes, under any circumstances. If you still encounter problems in H mode, it likely indicates that the underlying issue is not solely a matter of the peak bitrate.

Flow Motion v2 is designed to completely eliminate what was one of the most insidious of the GH2's reliability flaws: Fallback Mode. The reason the unhacked GH2 rarely fails in an overt manner is because it's configured to surreptitiously plunge into a coarse, low-quality Fallback Mode whenever it's unable to handle the bitrate demands placed upon its encoder. In my view, the fact that this can occur with absolutely no warning to the user makes the unhacked GH2 completely unsuitable for all but consumer purposes. In my work, individual video takes can be botched for any number of reasons and an occasional equipment failure is a routine occurance. What would be much worse is if I did not have full confidence that every one of my completed clips was recorded flawlessly at the intended level of qualtity. That is what I crafted Flow Motion v2 to guarantee.

The 720p mode on the GH2 has an inherently lower stability margin than the camera's modes with lower frame rates. While it's quite possible to insure that it will continue to record under all circumstances, that can only be done by allowing it to resort to Fallback Mode in demanding circumstances. With Flow Motion v2.02, the compromise I settled on was to stabilize it with a mild degree of fallback in only the most extreme conditions. If I used a heavier amount, it would start to be perceptible in both SH and H modes. If you're interested to compare the difference, the 720p modes in Flow Motion v2.01 allows no fallback compensation at all, and are suitable for use with manual-focus lenses in manual exposure mode.
 
Yea I agree with everything you said about fall back mode. However, have you ever encountered it in low motion or static scenes?

Really I am looking ahead to the 1080p @ 60 FPS and 720p @ 120 FPS modes. I wonder how those modes are going to react? I guess we will be required to use high speed cards with those hacked modes. They will definitely require a lot of tweaking though. Should be fun.
 
Yawn.

I have seen photo quality screen captures from hacked footage.
I have NOT seen photo quality screen captures from un-hacked footage.

The End.
 
The vexing problem with the GH2's Fallback Mode is that it's usually quite difficult to spot with the naked eye, that is, until you project it at 2-4X magnification or start grading it in post-production. During my testing of Flow Motion v2, I discovered examples of Fallback Mode in unhacked GH2 footage of commonplace streams of water. While this type of subject tends to provoke noticeable macroblock artifacts, it doesn't always demand peak bitrates from the encoder. I suspect that Fallback Mode can occur in any situation involving sharply focused, highly detailed motion, including panning shots with deep depth of field. However, had I not been intent on confirming that Flow Motion v2 footage was free of these recording flaws, it's very likely that their presence in unhacked GH2 footage would have escaped my notice.
 
At this point, the only patch that I've tested and confirmed to be failsafe from Fallback Mode is Flow Motion v2. In the early days of GH2 patch development, our knowledge of the encoder was incomplete and many of the first generation of patches suffered from Fallback Mode and other reliability issues. At this point, cbrandin's invaluable Stream Parser analysis tool is able to positively identify exactly where Fallback Mode occurs in any GH2 video file.
 
Bassman2003 said:
It is very simple...More information is always better. AVCHD at the "normal" bitrates is pretty restrictive. The bare minimum to get a decent image imho. I prefer not to do anything at the bare minimum so the hack gives one the opportunity to move the GH2 out of the that category.

Frustrating to me how camera makers and some shooters want to limit the information recorded saying we don't need it. Well if we don't need why do the folks who make the "big" movies want/need it? - Because more information is always better.
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Well from Panasonic's end they probably want to make sure their implementation of AVCHD is playable on all their TV's and Blu-ray players. Also keep in mind that Panasonic always designed this thing to be a consumer camera and only through 3rd party firmware have the capabilities of the camera really been unleashed.
 
the latest flowmotion patch is just sick! If your not seeing a difference, your not looking at the right things, because it's night and day. It's solidn to. Only twice I froze it and got the message that it cant keep up, but once was when I shot iso 12,800 in a veryh dark room with a regular class 10 card. The second time I was in 720p sh recording mode. But the odd thing was I hit the record button again and it was fine. So I don't even consider it to be a glitch, may have been because it was pressing the record in that mode directly after formating. who knows if that was why. But to get back to my point flowmotion is by far the best patch to date.
 
Heck,

I am happy with the stable 44 mbps for 720p60 hack. That doubles the stock bitrate and I can use my class 6 32 gb cards.
 
I have tested almost every Driftwood setting, and the one I use the most is the V3b Rocket (variable bitrate setting with AVC Intra matrix). I really didn't see the point in using a constant bitrate patch when I had scenes with low motion, I see that as a waste of recording space in a way... This patch adapts perfectly to the situation and gives better quality than stock firmware, if anything the color correction is easier with a hacked bitrate.

So if you are going to use one setting and want to save card space while getting really sweet quality, try the Rocket setting.
 
So if you are going to use one setting and want to save card space while getting really sweet quality, try the Rocket setting.
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If it's working for you then go with it. After experimenting with a bunch of different patches with different scenes and such, I find For me Flowmotion 2 to be the best. From here on out, I have no reason to switch or try any other patch. FM2, Does everything I need it to, and without issue. It's honestly like shooting a new camera with an amazing IQ. I only wish the GH2 build quality was better and more durable. But hey, it could be worse I guess.
 
HHL said:
Yawn.

I have seen photo quality screen captures from hacked footage.
I have NOT seen photo quality screen captures from un-hacked footage.

The End.
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Sorry but this is really bulls*%t, give me an evidence please.

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really ugly or?

These days, i will make a comparison between a none hacked gh2 and flo motion hacked gh2 in lowlight with motion and grading. lense will be the 20mm f1.7.
 

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If there is a safe hack, I have not found it. Flowmotion is the most reliable I have tried so far, but I always have another cam running.
As far as the IQ difference, don't forget that you have to push the vid in post. Flowmotion gives you more to work with.
 
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