The Panasonic GH1/GF1 debuted in 2009 with a sensor in between 16mm and 35mm Academy size. It is approx a 2x crop sensor related to SLR terminology. The short focal distance allows the usage of any lens built for cameras – except the CS-mount lenses. Russian hacker tester13 figured out a way to modify the firmware to give custom recording rates – among other goodies. At this point in time, the GH1 has the best recorded image out of ANY camera less than 10K. Here is my article about installing the firmware for noobs.
This is a very simple tutorial that will attempt to organize everything for first time users.
Video is essentially a sequence of still images taken 24,25,30,50 or 60 times a second. Also, during a video recording there is a spatial relationship between successive stills. The camera records in 2x formats – AVCHD and MJPEG.
MJPEG records video as a sequence of JPEG stills (also called an intraframe codec). Hence, it can be easily edited on any computer. On the flipside, it is less efficient than AVCHD for storage. Both the GH1/GF1 only record 30p videos in MJPEG.
AVCHD uses the spatial relationship to record each frame as a DIFFERENCE of stills (called an interframe codec). This encoding is called a Group of Pictures (GOP) encoding. So, the sensor takes its snapshots which it passes to the encoder. The encoder takes the first snapshot, saves it as a still, and calls it an I-frame. The next few frames are encoded as a difference frame, encoding only the regions that have changed. These are called P-frames. There are also D and B frames, that are variations on this theme. If there is lots of movement (i.e. foliage on a windy day, or ocean current), the encoder gets stressed trying to calculate P-frames. This causes errors while using your camera.
Finally, we need to understand colorspace. If you have ever painted, you know that all colors are composed of the primary RGB (Red-Blue-Green) spectrum. So, a basic representation of a color image involves at least 3 values for R, G and B. Depending on the color depth (8,16 or 32-bit), this can mean 24, 48 or 96-bits per pixel. That is a LOT of information. Hence, another colorspace is used for encoding stills and video – called YCrCb. The intensity of light on a pixel is called luma, and the color value (a composite of Red, Green, Blue) is called chroma. In practice we only need 3 values, Y (luma) Cr (Y – Red) and Cb (Y-Blue). The value of green can be derived from these 3 values. Now, the human eye is more sensitive to luma than chroma. So, a common scheme is to reduce the sampling for Cr and Cb. This is called 4:2:2 colorspace, where luma is sampled at twice the rate of chroma. A more efficient alternative is to sample Y at twice the rate of Cr and Cr at twice the rate of Cb. This is called 4:2:0 sampling. Obviously 4:2:2 sampling will stress the sensor circuitry and cause more errors.
MJPEG can offer 4:2:2 or 4:2:0 sampling, while AVCHD can only offer 4:2:0 sampling.
Finally we need to understand interlaced vs progressive footage. Consider standard NTSC rates of 60i or 30p. In progressive mode, a sequence of 30 still images are written to disk in 30p mode. In interlaced mode, the encoder reads the odd or even lines on each image. Thus even though the sensor is sending out 30 images each second, the encoder takes each image and encodes the odd lines on odd frames, and even lines on even frames. In interlaced mode, there are 60 calls to the encoder to write 1920×540 resolution images per second. In progressive mode, there are 30 calls to the encoder to write 1920×1080 resolution images per second. Obviously a progressive encoding for the progressive image generated by the sensor is more efficient but also more stressful for the encoder.
Having read this, lets start with the hack.
1. Use a Windows PC for this. Things can work with Parallels or other emulators on a mac. Winebottler can cause a problem where the bottom part of the hack utility (with options for various hack settings) is not seen.
3. In the past, we had to modify each individual setting. It was a tedious task to setup a GH1 or GF1. Now we can have multiple settings files that can be used, as long as they are in the same directory as the ptool. Check out the Ptool FAQ and the various settings available.
4. Now I will offer what I do for my shoots. I use AVCHD as its the only choice for 24p/25p footage. 30p is pointless unless all you need is to post videos on Vimeo. There are 3 hacks, available for the GH1 which offer Reliable, Turbo and Extreme modes of the hack (my terms). I use 3 cheap SD cards, some 16MB cards I have lying around. Format them in the camera and load 1 setting per card as shown in the FAQ above. Use a sharpie to write down Reliable, Turbo and Extreme. The 3 settings are provided the lpowell.
All three patches are switchable between NTSC and PAL modes, and support multiple language selection, unrestricted recording time, and third-party batteries.
The robustness is obviously less for Extreme and Turbo than Reliable. At night, or for places indoors use the Extreme patch. If it does not work, use the Turbo patch. For dense foliage, or clip with running water use the Reliable patch. lpowell has stated that the Extreme patch is at least as robust if not more than the Turbo patch. Since the patch is new, I may update this information after it has been widely tested.
5. After recording, you may decide to view the video files for errors or out of curiosity. Please download cbrandin’s StreamParser - for more fun.
@The_M First off you posted in the wrong topic, this is a GH1 topic. But to answer your question, make sure there is 2 underscores in between GH2 and V11 so it looks like this, GH2__V11.
Hey guys, I'm having trouble saving my firmware for my GH2. I'm running PTools3.62 and using firmware GH2_V10E. In PTools I have version increment checked and set at 1. I've tried renaming the file GH2_V11 and all variations that I can think of, but each time I get the error "Bad file name, Camera won't be able to read Such a file". Any ideas?
@ADE It's tough to say. You could either ask the person you bought it from or just install a new hack. If you install a new hack, just be aware of how to get to the language settings before you rehack it. A friend of mine got a GH1 from China with the hack already on. He wanted to update to a newer patch, but once he did everything was in Chinese and we had to reference my GH1 to get him to the language setting where he changed it back to english.
It depends on the scene you are shooting, and the exposure. I've not seen any footage go over 34mb/sec in the 720/60P mode, without crashing. Keep in mind that when they say "75mb/sec" patch, that is the theoretical maximum limit that you could achieve. For most scenes, your footage will be around 44mb/second, with occasional spikes higher, and that's shooting in 1080/24P.
Yes, I have the same problem when shooting 720/60P, as do others-it's not a card issue. Change from SH to H, and you will be fine. The max you can get out of 720/60P is around 30mb/second. So, you can go into Ptools, and manually edit the H setting for 3000000(I think that's the right amount of zero's), and it won't crash-done. I've noticed that when 720/60P footage approaches a highly detailed scene, at around 34mb/sec, it crashes every single time.
This weekend I re-hacked my GH1, applying the the 50mpbs (the blackout?) version as i wanted to shoot at 720p60fps this weekend.. it crashed ALL THE TIME due to write speed. Before I left on the Friday, i had put the 75mbps hack on, but got the same error when testing in the garden.
I can't find much explanation for this, other than the memory card? I admit, it was a camping trip and I was shooting in the forest... it was sunny too, so it may have just been a perfect storm? In almost all situations though, writing to camera failed, and failed even when i stopped down exposure. I am using transcend class 10 (32GB) in my GH1. It has always been absolutely fine with the 100mbps hack on 1080p24fps,, so i don't think it's a dud?
Do others have this problem? I have seen LPowell say that he thinks all failures now are due to the cards, not the hack.. but then i see plenty of folks saying they are using the transcend's without problem...
Numbering strategy for different firmware hack versions
Just give them each a unique number, like 1.37, 1.38 etc. I have those numbers with a short description behind them on my hard drive. Of course, I have to lose the description on the SD card for the firmware to be accepted. But keeping different numbers allows you to at least recognize each individual hack by something.
The suggestion is to always check the Prevent Version Compare check, which resets the firmware version in the camera to 0.0. So you won't be able to recognize the firmware version in the camera itself, but it allows you to always overwrite the firmware by any other version, which includes the original firmware. Be aware that the original firmware does require a version number higher than 1.32 to be accepted as an upgrade because the original firmware always performs the version check.
@zscream Thanks for the detailed explanation. Just got few questions regarding changing the hacks. If I want to carry all three patches on three different cards and change the hacks depending on the suiting conditions, what version numbers should I give to different patches ? Also wondering if that version incrementing applies only when you want to go back to panasonic factory settings or also when you want to change the hack type say from Turbo to extreme?
I have the Gh1 "extreme" hack loaded on my camera. I loaded it via a Transcend Class 10 card (had problems with it), now will be upgrading to a SanDisk Extreme. When I get the new card, should I format the memory card on my GH1 first and then follow the same steps from the beginning again?
First, your file name is just wrong. Look at original firmware file name and look at one you cited. Second, you do not need to format SD card if it is hard to do, it is enough to delete all files.
Hi gurus, I have another question related to above. I have a JP GF1, and I am trying to figure out how to format the SD Card in camera using japanese language menus and manual. I have not been successful. Any is greatly appreciated.
Hi GF1 Hack gurus, I have a newbie question. I am trying to hack a GF1 using the step by step information given above. When I try to Save Firmware, using a name GF1_132 (increment of 10 above GF1_122 firmware I am using) , I get a error "Bad file name, Camera won't be able to read Such a file". Please let me know what I am doing wrong here.
Vitaliy, I have a GF1 I haven't hacked yet. The stock camera turns off video-out while recording. Does your hack enable video-out - HDMI (preferred) or composite AV?
HDMI video out is possible on Sony NEX-3 & NEX-5 while recording.
Is this possible on GF1/GH1, GF2/GH2 or is there a hardware limitation?