GH2 Hack Considerations

when I say 40.000.000, 32.000.000, 28.000.000, 24.000.000 it is what you will type in the ptool to create your hacked firmware. Of course you will not type the DOT, you will type 40000000 and so on...

Resolution charts does not show diferences in hacked bitrates. when camera shots something with lots of white color the bit rate decreases below the data rate you type in ptoll. to see the diference in fotage you must shot a very complex scene.

Best Balance price / performance hack is 40000000 mbps with a kingston 32gb sdhc class 10 card. It is very hard to see diference in more bit rate than this in a full hd monitor, it is good enough for post corrections, good organic texture and remember you will deliver the media in a more compressed output so do not worry about more than 40000000 mbps.
 
Okay, then how are green screen shots improved with higher bit rates via the hack, not considering benefit on improved motion.
 
I do not think motion will be better enough with bit rate higher than 40000000 to deserve the money to buy cards. and compression in deliver media will hurts it anyway.

about chroma key / green/blue screen: even the highest bit rate footage will have some grain, texture changing in each frame, even in iso 160. so the solution for a good "key" is not increase the bit rate. the solution is to apply a noise reduction in the footage before doing the "key". the noise reduction will flat the texture/grain/noise/artifacts and the "key" edges will flicker less. this is the secret for a good "key".
 
An interesting point:

sometimes the camera record a lower bit rate than you type in ptool. It happens when the scene has flat colors and white colors.
for example: you typed 40000000 in ptool, this will give you 5MBps. But if you record a flat white wall the datarate will be something like 2MBps. The camera just use the full datarate in a complex scene and in low light situations. Another reason to not use more than 40000000 mbps. probably a green/blue screen will give a lower bitrate than what you typed in ptool due to lots of flat colors in the scene.
 
dishan said:
But between you and me, I agree that pushing the bitrate has arguable value at best. ISO hack, on the other hand, is very useful!
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I don’t know about you but shooting ISO 12,800 in color really has way too much noise for my tastes. It looks good for B&W though.
 
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TheDingo said:
High bit rates offer two across the board advantages that are useful for almost any delivery format:

1- Lower noise at higher ISO settings
2- Smoother image motion

If you don't care about either of these issues, then the hack might not be for you.
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This is not correct. The higher the bit rate the more accurate the noise is. It also makes the noise more apparent instead of less apparent.

Bit rate and GOP have absolutely nothing to do with smoothness of the video. Shutter speed and frame rate have everything to do with that.
 
Kholi said:
Even the most expensive cards are stupid cheap

You can get 30mb's Sandisks that work with the 176 patch, 16gb, or 30.00

There's NO reason not to use the patch other than spanning.
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The 176 mb/sec patches are not stable with 30 mb/sec cards and any of the longer focal length m4/3s lenses. The only cards that work for those lenses are $150+. That is not what I would refer to as "stupid cheap".
 
JMZ said:
The codecs used in broadcast are not the same as DVD or BluRay. It's not apples to apples. To put it simply it's not just about how much total data is contained in a video file. There's also the issue of how that data was created and how much of the original you will get back when it's transduced again back into images. Long GOP is also a pain to edit. It's less of an issue than it used to be but it can wreak havoc with your editing software. And of course, when you want a file to stay high quality even when compressed you have to start with a higher quality original. No matter what CSI shows might otherwise imply.
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This is the single most overlooked benefit of the low GOP settings. For frame accurate editing GOP = 1 is essential.
 
PaPa said:
So what seems to be the consensus on all of these hacks? I have read so many different opinions from users that I, like others I'm sure, am getting very confused.

what do most seem to go for? 46mb? 30 something? What is the best balance between stability, storage space and quality?
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These settings are completely stable for all memory cards in all situations. I would love for anyone to show me unedited footage that shows a difference between these settings and any of the higher bit rate settings.

http://www.personal-view.com/talks/...ault-most-popular-patches-in-one-place#Item_5

Please note that if you need frame accurate editing then the lower GOP settings would be essential. Other than that and you are just “wasting space”.
 
Snazzy Flapper said:
Has anyone shot resolution charts, etc. using the hack with the different bit rates and settings?
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I have shot resolution charts and low light pattern images comparing them and I have never seen a difference at all. I will try to post the footage this weekend. The problem is that the high bit rate footage is so big I can’t post very much of it to Vimeo before I hit my cap.
 
iso 12800 is not ununsable. it is very usefull. it let you use a slow ultra wide angle lens at night, and also shot in very dim places with fast lenses.

you can clean the noise with a noise reduction software or plugin.

about editing. you do not need gop1 for editing you can shot gop12 and use a intermediate codec to do editing.
also, the high bitrate AVCHD is very dificult to computer to handle, sometimes plyback gets jerky, so an intermediate codec is a must. mpeg2 422 works great for an intermediate codec. of course to use an intermediate codec can hurt the footage a bit, but will you chose a bad avchd editing workflow instead of it?
 
mpgxsvcd said:
These settings are completely stable for all memory cards in all situations. I would love for anyone to show me unedited footage that shows a difference between these settings and any of the higher bit rate settings.

http://www.personal-view.com/talks/...ault-most-popular-patches-in-one-place#Item_5

Please note that if you need frame accurate editing then the lower GOP settings would be essential. Other than that and you are just “wasting space”.
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So the 42mbs is basically the winner?
 
well, that's good to know. This all seems very complicated for someone who has not been following from the beginning. Hopefully this brings simplicity to others like me.
 
Thanks guys.
I may try 42mbps to save space and of course stability.
Any better hack for 32GB 30mbps C10 sandisk card. Do not want to install the high end hacks which takes up a lot of space.
I now have four 32GB 30mbps instead of getting one 64GB.
 
Snazzy Flapper said:
Has anyone shot resolution charts, etc. using the hack with the different bit rates and settings?
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Testing methodology and presentation don't seem to carry much weight in this section, we get subjective wording like : "Long-GOP motion looks bad" or "True digital cinema look" or even "more organic looking grain", which is pretty-much meaningless.

Has anyone ever seen a true A-B test high bit rate hack vs. original GH2 firmware?

Most rational people realize the big issue with this camera is DR and color space and no hack is ever going to fix that.
 
aguia said:
Testing methodology and presentation don't seem to carry much weight in this section, we get subjective wording like : "Long-GOP motion looks bad" or "True digital cinema look" or even "more organic looking grain", which is pretty-much meaningless.

Has anyone ever seen a true A-B test high bit rate hack vs. original GH2 firmware?

Most rational people realize the big issue with this camera is DR and color space and no hack is ever going to fix that.
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I would love to see this too. With original .MTS files...not the useless youtube or vimeo tests. Even at 1080p, their recompressed bitrate is too low to tell us much. Either that, or the differences aren't much to talk to about.

I don't understand the log-GOP motion complaints either..... I own an HMC150, and at work, we use an HVX200. Those two cameras are about as close as you can get, in terms of just isolating the codec, and I've never ever ever noticed a motion cadence difference, and I'm pretty sensitive to that sort of thing.
 
I think a lot of people here are confusing an aquisition codec with a delivery codec. The whole point in having high bitrate capture is so that you have the best quality master footage to work with. For some odd reason Panasonic decided to incorporate a delivery codec into their cameras (ie. AVCHD max 24mbps) even though no-one would be dumping their rushes directly onto BD Disc as final masters - they would be edited (even a basic top 'n' tail edit per shot) and re-encoded for Bluray before burning onto disc. This is where the hack comes into play, as it allows you to bump up the bitrate to something more acceptable for an aquisition codec - something that ANY camera manufacturer should have done in the first place. Also if you are shooting for broadcast in the UK, the BBC won't allow anything under 50mbps to be classed as HD, which is why we had to go for Canon XF305s as replacements for the Sony Z1s and have just bought a load of XDCAM 500s to replace our Betacam SX and Digibeta cameras.
 
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