GH1 AVCHD Hack -- only 14Mbps?!?!

It has been said before and it is worth repeating again: not all encoders are created equal. If arithmetically XX.X is larger than YY.Y doesn't mean that MJPEG footage with bitrate of XX.X Mbps has better "image quality" than AVCHD footage with bitrate of YY.Y Mbps. 5D has a different AVCHD encoder, Red One shoots in RedCode. Bitrates don't mean anything when you start crossing boundaries.

I see what you're saying and you're absolutely right a 20mbs super efficient codec will "look" alot better than a 100mbs super inefficient one that's only getting 15mbs of efficienty or something like that. But still, out of curiosity do you or anyone know the rates for 5dmkii and Red one in MB/s?
 
5dmkii files was with average 38 Mbps , but profile of h264 baseline@L5.0
about red codec it is LossLess and bitrate on of 224/288/336 Mbps; information from : http://en.wikipedia.org/wiki/Red_Digital_Cinema_Camera_Company


FYI:
h.264:
baseline profile = Primarily for low-cost applications ... (sorry mkII)
High Profile = The primary profile for broadcast and disc storage applications
GH1 use one of "High Profiles" with level 4.0, howewer with hack stream is over requirements of 4.0. So codec used inside seems created with looking on future models, seems simple need correcting of headers. In future possible will be found hacks for 4:2:2 (as for mjpg currently) 4:4:4 and/or more than 8 bit sample depth
 
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I think he means make the camera work in terms of bitrate, not producing great images. Those last few words you added really changes the context of it all=)

OP - you have yet to post what scenes you were actually shooting, whether its low light low detail or daylight low detail or high detail when you got those low bitrates. for 60Mb settings what you are getting is quite low even at 20Mb

No I haven't, haven't had the time to do so, but hope to shot some this weekend. I will try and post my results.
 
I know that that wasent directed at me, but I'm using a Delkin Class 6 16GB eFILM Pro Series card.

I get 60Mpbs with the hacked mjpeg setting no problem. But with AVCHD the most I get is 20Mpbs. But then agian, I will try more detailed scenes hopefully this weekend.
 
Try shooting any high detail (grass, the papas screen of death etc...) with that class 6 card and your gonna get an error. You need a class 10 card to really be able to avoid the crashes (just what I've found) esp with 24p checked.
 
Try shooting any high detail (grass, the papas screen of death etc...) with that class 6 card and your gonna get an error. You need a class 10 card to really be able to avoid the crashes (just what I've found) esp with 24p checked.

Cool thanks!
 
Try shooting any high detail (grass, the papas screen of death etc...) with that class 6 card and your gonna get an error. You need a class 10 card to really be able to avoid the crashes (just what I've found) esp with 24p checked.
That really depends on the card. I have a class 4 Toshiba 16Gb card that I can safely run "C" settings on. I haven't had a card error yet, other than the static scene error that's been reported. The best bet is to speed test your cards and see if they can handle the high-speeds required, regardless of the class designation.
 
I have only been able to shoot grass and the papas screen of death using a sandisk extreme III class 10 30Mb/s card. All others have crashed (even then I still get the speed error every once and awhile). I can use a class 6 transcend card that I have for most other things but for high detail with "c" settings native 24p clicked, I have to use my class 10 sandisk extreme. I have heard that the sandisk even outperforms the panasonic class 10 but I haven't tested them against each other so I take it with a grain of salt. I am also only using manual fd lenses as I've heard (but again have not tested) that the panasonic and Olympus af lenses can cause crashes as well (don't know if this is due to the sharpness or the nature of the cam having to couple with the lens, my fd lenses are pretty freekin sharp tho...). I'm not trying to say that all my personal exp is to be taken as the be all and end all (lord knows that there are more proficient testers out there) but I have seen several people report that without a class 10 card (and granted this should be a tested to be high bitrate class 10 card) crashes are occurring on high detail static shots.
 
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