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Apefos Adapter
12-08-2011, 12:20 PM
Some considerations about the rack:

1- Broadcast compression is much more compressed than the hacked footage, dvd output and web output does not take benefits from the hacked footage due to resolution and data rate, so the main reasons to increase data rate would be:
A- for the videomaker / filmmaker have a more pleasant experience seeing the footage?
B- for a film transfer or DCP (digital cinema) output and project in a theater?
C- BluRay output for a maximum 1 hour and 15 minutes at 5 MBps?

2- So would the iso limit hack up to 12800 be the main reason to do the rack?

dishan
12-08-2011, 02:54 PM
I may be wrong, but I don't think broadcast and blueray footage are encoded with the same codec, so the bitrates don't translate.
These cameras need to encode video in real time, which is very taxing on the processor. High compression rates (like those used on blueray) take your computer a lot longer to transcode than the camera does to record.
Part of that is because the camera has optimized video encoding processing, but the other reason is because the camera is recording in a codec that is better suited for real time compression. The downside is that you don't get the same amount of quality per megabit as a more CPU-intensive multi-pass encoding.
So, I think what some folks are doing is pushing the bitrate as high as they can go in camera, that way when it gets recompressed into a different format (with a lower bitrate), it will still look good.

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!

Ian-T
12-08-2011, 03:02 PM
I don't think people understand why the bitrate needs to be pushed so high. I don't completly understand it myself but what i do understand is in order to get those I frames which is at GOP1 the bit rate needs to go higher. He(driftwood in this case) is not just doing it to do it. There is a reason for his method (which he can explain much better than me).

TheDingo
12-08-2011, 03:28 PM
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.

Apefos Adapter
12-08-2011, 03:31 PM
another points to consider:

higher bitrate can give a better chromakey results

also the image tweaking like color correction / brigtness, contrast, gamma improvements can give better results in post...

kingston class 10 cards works great for 40mbps 5MBps

for higher bitrates the cards starts to became very expensive and less record time per card, also more storage space in computer

Kholi
12-08-2011, 03:41 PM
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.

JMZ
12-08-2011, 04:22 PM
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.

GH2user
12-08-2011, 05:26 PM
I use the hack because:

1. Long-GOP motion looks bad. 1GOP or INTRA looks like film or Red. True digital cinema look.
2. With the stock GH2 recording, the shadows have terrible banding and you can't manipulate the levels at all in post.
3. All around reduction of artifacts and more organic looking grain.

M. Gilden
12-08-2011, 05:42 PM
There's NO reason not to use the patch other than spanning.

http://www.youtube.com/watch?v=pWdd6_ZxX8c

: (http://www.youtube.com/watch?v=pWdd6_ZxX8c))

Ian-T
12-08-2011, 06:21 PM
http://www.youtube.com/watch?v=pWdd6_ZxX8c

: (http://www.youtube.com/watch?v=pWdd6_ZxX8c))LOL...smart alec.

M. Gilden
12-08-2011, 06:58 PM
LOL...smart alec.

LOL- I used to say this over by the Canon section, when we were pushing Qscale values in Magic Lantern. Higher bitrates are of arguable value in most situations. But I do think Dishan and JMZ hit the nail on the head about codecs being different- just because blue ray and broadcast bitrates are lower doesn't mean the camera is recording at the same quality per bitrate. Sometimes a little oomf can be beneficial, but these numbers sound insane!

TheDingo
12-08-2011, 06:58 PM
There's NO reason not to use the patch other than spanning.

...Apparently the new 95 MB/sec SanDisk 64 GB SDXC ( $200 at B&H Photo ) cards will span properly even when using the 176 Mbit SeaQuake patch. ( I plan on ordering a card next week to test )

Perry Wilson
12-09-2011, 08:04 AM
I can span all day long on any GOP1 patch driftwood has made on SD extreem pro 45mb/s 8gb cards

toxotis70
12-09-2011, 09:03 AM
what bitrate did you used ?

PaPa
12-09-2011, 09:58 AM
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?

Gary Huff
12-09-2011, 10:14 AM
I'm more interested in knowing if there's really any difference between 95mbps and the 176mbps. It seems 100mbps is the magic number of pretty much any codec as far as size vs. quality is concerned.

PaPa
12-09-2011, 10:59 AM
100 is the winner then? Is this the general consensus?
What cards can write data at that speed?

Apefos Adapter
12-09-2011, 11:58 AM
The following settings I think are the best, it is very dificult to see difference in a fullhd monitor using higher bit rates

for class 10 card: 40.000.000 and 32.000.000 (kingston 52 usd for a 32gb card class 10)
for class 4 card: 28.000.000 and 24.000.000 (kingston 32 usd for a 32gb card class 4)
if you have a mix of class 10 and class 4 cards: 40.000.000 and 28.000.000 (and chose taking into account the card in use)

I strong recomend KINGSTON cards, they are reliable and data rate good enough for data rate above.

PaPa
12-09-2011, 12:04 PM
The following settings I think are the best, it is very dificult to see difference in a fullhd monitor using higher bit rates

for class 10 card: 40.000.000 and 32.000.000 (kingston 52 usd for a 32gb card class 10)
for class 4 card: 28.000.000 and 24.000.000 (kingston 32 usd for a 32gb card class 4)
if you have a mix of class 10 and class 4 cards: 40.000.000 and 28.000.000 (and chose taking into account the card in use)

I strong recomend KINGSTON cards, they are reliable and data rate good enough for data rate above.

What are you refering to when you write "28.000.000 ?

Chris Adler
12-09-2011, 12:08 PM
Has anyone shot resolution charts, etc. using the hack with the different bit rates and settings?

Apefos Adapter
12-09-2011, 12:24 PM
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.

Chris Adler
12-09-2011, 12:35 PM
Okay, then how are green screen shots improved with higher bit rates via the hack, not considering benefit on improved motion.

Apefos Adapter
12-09-2011, 12:42 PM
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".

Apefos Adapter
12-09-2011, 12:54 PM
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.

mpgxsvcd
12-09-2011, 01:12 PM
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!

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.

mpgxsvcd
12-09-2011, 01:16 PM
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.

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.

mpgxsvcd
12-09-2011, 01:17 PM
http://www.youtube.com/watch?v=pWdd6_ZxX8c

: (http://www.youtube.com/watch?v=pWdd6_ZxX8c))

And reliability, and clip length, and storage space, and so on.

mpgxsvcd
12-09-2011, 01:18 PM
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.

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".

mpgxsvcd
12-09-2011, 01:21 PM
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.

This is the single most overlooked benefit of the low GOP settings. For frame accurate editing GOP = 1 is essential.

mpgxsvcd
12-09-2011, 01:26 PM
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?

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/discussion/953/gh2-patch-vault-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”.

mpgxsvcd
12-09-2011, 01:33 PM
Has anyone shot resolution charts, etc. using the hack with the different bit rates and settings?

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.

Apefos Adapter
12-09-2011, 01:34 PM
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?

PaPa
12-09-2011, 02:44 PM
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/discussion/953/gh2-patch-vault-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”.

So the 42mbs is basically the winner?

Apefos Adapter
12-09-2011, 02:55 PM
So the 42mbs is basically the winner?

Yes, it is.

But I preffer 40 / 32 instead of 42 / 35 because it gives 5MBps / 4MBps better for slow cards.

PaPa
12-09-2011, 03:25 PM
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.

cam123
12-09-2011, 03:27 PM
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.

aguia
12-10-2011, 02:15 PM
Has anyone shot resolution charts, etc. using the hack with the different bit rates and settings?

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.

DBP
12-10-2011, 03:27 PM
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.

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.

Energy80s
12-11-2011, 03:13 AM
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.

Apefos Adapter
12-11-2011, 10:04 AM
This is what you need to see to understand hacked vs unhacked gh2.
Download the 1920x1080 version available on vimeo and see in a full hd monitor.
Observe when the videos shows the 400% blow-up.

http://vimeo.com/27883337

aguia
12-11-2011, 04:04 PM
This is what you need to see to understand hacked vs unhacked gh2.
Download the 1920x1080 version available on vimeo and see in a full hd monitor.
Observe when the videos shows the 400% blow-up.

http://vimeo.com/27883337

This is a bad test to judge anything by. The majority of the scene is in open shade. It might be an acceptable test for trying to "break" a codec but I think the move is too slow to accomplish that.

So far most of the good examples I've seen from hacked GH2s had lighting situations or setups that really showed the potential of the sensor but I would never attribute to the bitrate of the codec, and I guess the potential of shooting ISO 12K or such has pretty limited appeal for what I do.

As for the people that actually believe the IQ of a hacked GH2 even begins to approach an AF100 using an outboard recorder all I can say is "dream on".

The GH2 is a great tool, I love mine. I'm installing the new Panasonic firmware tonight and maybe next week if I have some time I will shoot some tests to compare it to my AF100 and if I can get my hands on the charts I might even try an A/B hack/unhacked test.

JMZ
12-11-2011, 05:25 PM
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.

Energy,

Thanks for posting this. You break it down quite nicely. It's about having the highest quality acquisition format you can going in so you keep as much quality as possible going out. It's that simple. I might watch HD quicktime versions of movie trailers online. But we all know those images didn't originate as quicktime files. So they still look quite good in most cases. If someone can't see the difference in the final product of one hack versus another; then they should use what they think looks best. Heck, I believe you should approach most of your image making choices this way. Use what works for you and have fun doing it.