Personal View site logo
Seeking GH2 hack for specific requirements
  • Hi all, Im a very new DSLR user, and have grown up doing all my uni work on 'camcorders' i'v recently perchanced a GH2 (Defult 14-42mm lens). and have a Class 10, 45/mbs sandisk Extreme 32GB card. (cant afford bigger / better)

    Im looking to shoot concerts with it, (as the one of the cameras along side my 'camcorders' as part of a multicam set up) so need as higher quality and good low light performance, as about a hour's worth of footage would fit onto that card. (if that makes senses as most the gigs i work are no longer than a hour in length) 24/25fps in 1080i/p (i'm indifferent as i know what im asking is already very specific)

    I know nothing of GOP or anything technical, so try keep your advise dumbed down for me please haha

    Any help would be greatly apprecated,

    All my Best:

    Wil Henry Silent Syndicate Productions

  • 20 Replies sorted by
  • @Wilrus Given the recording times you are looking for, here are a few to look at.

    Sanity 5.1

    No Adverse Affects

    Cake (a little higher bitrate than the other two, though)

  • @thepalalias Thanks for your fast response, im guessing higher bitrate means it will fill up the card faster? (yes im that new to all this) i'v seen some of the driftwood things, they look great, but im predicting they would fill up my card way to fast? of those 3, which would you say is best? what separates them?

  • Basic answer is this. The patches let you use the higher ISOs, which is great for low-light. But their main enhancement is to enable higher bitrates. This means that the camera performs less data compression, and the motion in the images is much cleaner and more precise. This doesn't make the camera perform much better in low-light conditions. It may make it easier to brighten things in post, because the images have less noise. But for low-light shooting, your best bet is to use higher ISOs and fast lenses.

    As for patches that give you long recording times... well, the patches enable higher bitrates, which eats up memory storage, and the spanning also becomes unreliable. The only memory card that spans reliably at really high bitrates is the Sandisk Extreme Pro 64gig memory card. If you don't have that card-- if you're using a perfectly good Class 10 card-- then the only patch you should use is Cake. That patch spans reliably for me on the lesser cards, and you get decent bitrates.

    But don't count out using the camera's native firmware. It's still pretty good.

  • @Brian, Thank you very much for such a good explanation, i actually kinda know how it works now rather than just looking at footage and hoping haha under the circomstances i may give cake a try then :) can you quickly explain 'Spanning' though? Thanks again both of you!

  • @wilrus Brian is already sending you in the right direction, so I will just expand on this a bit. :)

    Getting the most out of all of this starts with a clear understanding of the building blocks.

    PTool: Lets you change Firmware settings. Each named "setting" (like Sanity or Cake) is a collection of values that are specified for those Firmware settings. The higher ISOs that Brian mentioned are single box that can be checked or unchecked, even if you want to use the factory default settings for the firmware on just about everything else.

    Spanning: The GH2 uses a maximum file size of 4GBs. That translates into 4096 MBs, or 8 times that if you are calculating in megabits instead of megabytes. When you look at a card in Windows or OS X, it tells you the free space in GBs. The settings on here are specified in mbps for their maximum video bitrate over time (though they can spike higher and are often lower). To find out how long it takes a given setting to fill up 4096 MBs, divide the mbps by 8, and then divide 4096 by this number to find the recording time.

    For example: A setting with 4.096 MB/s would give 1000 seconds of recording time before it filled up a file.

    When that file fills up, the GH2 tries to create a new one to follow it in the series. If it succeeds, there is no gap in the audio or video. This process of continuing the recording from one file to the next is called spanning. Be aware that it is something that is fairly demanding for the GH2 and the card and that different settings vary widely in their ability to consistently execute it (and their requirements for doing so). The factory default settings are generally reliable in this regard, with some rare exceptions discussed on this forum.

    Bitrates: The settings vary greatly in their bitrates. At the lowest end is Sanity 5.1 and the factory defaults. Sanity rarely records at the maximum bitrate it specifies. Their are settings that have bitrates over 5 times higher than the factory defaults, so that means you run out of space on the card 5 times as quickly. Givenn your criteria for record times, there are very few settings worth considering.

    EDIT 1-

    Differences in Settings


    Other than their reliability in spanning and what cards they will record well with, the different named settings vary in several ways. The differences may be subtle or dramatic depending on what you are filming and how you are doing so.

    Macroblocking: When a setting runs out of available bitrate or considers a particular detail to be unimportant, it renders it as a low detail square (or series of squares). This is called macroblocking. The hacked settings often have a lower chance of encountering macroblocking than the factory default/stock setting ones. If you notice macroblocking your footage with stock settings, there is a good chance that one of the named settings on this site will do better.

    GOP: During recordings, the GH2 can record each frame as one of three types: I, P or B. To keep things basic, we'll think of I-frames as "keyframes" where the entire picture is decribed (just like a JPEG) while P and B frames describe what has changed since the frame before. When there isn't much change from frame to frame, P and B frames allow you to either save a lot of bitrate (since they only specify the changes) or to make the I-frames really big (since you don't need to describe the whole picture over and over again if not much is changing).

    So why is GOP important? Because a setting that is most efficient when very little changes can run into problems when there is a lot of motion (these have low GOPs or even GOP1 "intra" where every frame is described in whole). Settings that are very efficient when there is a lot of motion are potentially less efficient in static shots where little changes (these are high GOP settings, including the factory default settings).

    If you throw a lot of motion at the factory default settings, especially combined with high detail, odds are high that you will end up with macro blocking.

    Noise: Noise is affected by the GOP, bitrate and other aspects specified in a given setting. With a GOP1/intra setting, the noise pattern gets updated every single frame. With higher GOPs, the change in the noise pattern from frame to frame is sometimes considered to be "insufficient change" for the codec to update it, depending on the setting - this is common with the stock settings. When there is limited bitrate available, the setting may also avoid allocating to much data to noise to make sure there is enough available for other parts of the image. That is part of what the extra bandwidth on some of the settings gets used for.

  • Both of you, thanks so much for all the help, i'll Look into Cake (rather than Sanity, as gig rarely run to a hour) and the explations are endlessly useful (i'v saved both of your messages onto my comp to refer back to haha) One last thing.. if i dont like the Hack, can i remove it / fall back to factory settings?

  • @Wilrus Yes, you can revert to the factory settings. Just start PTool, load the basic firmware, make sure the increment box is check for the version and save that firmware. Using that BIN file, you can revert at any time.

    By the way, in my experience the recording times for Sanity 5.1 are often longer than with Cake. Try both and check the bitrates on the files you end up with.

    EDIT: It is very important to check your real world results and not to just rely on the "recording time left" indicator on your GH2. The recording time indicator is always conservative - you will have at least that much time left on the card but it can often be more.

  • Sorry to ask, but what about stability with this hack? Can be leaved the camera recording alone? The video files can be reviewed on camera? I'm thinking to do the same as Wilrus, put a Gh2 and a Gh3 to record long sessions of video.

  • Don't forget @cbrandin 44Mbps setting. Very good for long recording times.

  • For concerts you want a big, fast reliable card and a better lens. Without this, you are pedaling backwards. If a longer recording time and higher quality is what thou dost require, I prithee look deep within thy purse, which will provide a happy passport to this exalted state.

    Flowmotion on the low setting will give you reliable spanning and a nice balance of bitrate and IQ.

    I'm currently using a Driftwood patch with the settings lowered so I don't have to deal with the CS6 rendering bug. If Nick recommends the cbrandin 44mps over his own patch it is either very good or he has been up late drinking again. Or both.

  • @DrDave Oh god the brandy! No, if you want low bitrate with a tad more quality than stock Long GOP Chris's setting has always pleased people. Personally, Ive never used it. As you know, none of my 24h settings go below 50M :-) BTW I'm not knocking low bitrate hacks.

  • I don't remember if Chris's 44 spans reliably--maybe it did in a later version, maybe Chris can enlighten us. For concerts spanning probably be a requirement.

  • On a class 10 card it didn't span reliably in 24H. I don't know about the faster cards. 24L spans.

  • @Wilrus I often found myself in scenario similar to yours so here is my experience on this.

    "45/mbs sandisk Extreme 32GB card" i use two of these cards for similar situations with Flow Motion 2 , ONLY in 24L, and really had never ever had issues with spanning. Recently had to do documentation of concerts and theatre performances and the camera was left running by itself until the card was full, if i remember correctly more then hour and half(hour and 50 min?still need to review the footage) on 32 gb card.

    It is not an intra setting so do not expect it to be one(image quality,etc) ;) but it gets the job done graciously and with peace of mind that you got "that performance" covered and it is clearly superior to stock image and in my eyes to all the other common spanning settings around.

    Regardless of settings you choose, one thing to consider is to NOT use the automated features(iDynamic, iResolution,etc) apart from AF if needed. They put extra stress on the cpu which can negatively affect spanning, etc.

    Another thing if you decide to use the Flow Motion setting is to try to use faster lens(panasonic 20mm f1.7 for example or similar) if you have access to some in order to use lower ISO. the higher the iso the more the noise especially in the 24L verision. Iso 1600 and after, sometimes is starting to push it a little too much noisewise. Of course noise can be cleaned up later if you have the time and need to do it.

    hope this helps.

    EDIT: Moon Trial 5 spanned for me on 24L setting with the 64gb/95mb SanDisk card.

  • Thank you everyone for all your feedback and advise! @driftwood as a non bias middle man, what do you believe would be more reliable for the job, @cbrandin 's @ 44mbs, or Flow Motion 2? (im guessing i pick between weather its H or L like i would normally on the camera... hacks dont add extra menus or anything do they? (i'm going to keep this thread running until my memory card arrives in the post, as i cant really test anything until then >.<) a huge thanks to everyone again who's participated again, even if you.

    (for the record, the camera would be focused and left on manual focus, and i could leave iDynamic and iResolution off too)

  • i ment to say: *even if you are just curious, all input is helping me out haha :P

  • If your choices are between my old 44mbs patch or Lee's Flow Motion 2, I'd go with Flow Motion 2 - it's much newer and Lee put a lot of work into it. I produced the 44mbs patch sort of to get people started. There are several guys here who have produced newer and better patches.

  • +1. Also memory cards are cheaper and faster.

  • @Wilrus Non biased? Spizz (co-developed with bkmwcd), Lee's FM2, DREWnet Trial 7 (or 8), each tried on L settings. Also a lot of people like Ralph's Sanity and Cake from Balazer get good reports. Try them all on a few scenes over an hour or two and decide what YOU prefer.

  • Looks like Nick covered the options pretty well...