Blackout-Powell Native 24p Patch - GH1 FTW!!!

Thanks everyone, it's great to see so much active enthusiasm for the GH1 even after its production run has finished. In retrospect, I think it's clear there were two crucial hacks that ignited the DSLR video revolution. First, Magic Lantern on the 5D Mark II brought 1080p @ 24fps to the forefront, and Canon responded with firmware updates to meet the unexpected popular demand. Next, PTool cracked the GH1 wide open, giving users an unprecedented ability to customize the camera to suit their own needs. While Panasonic's response has not been as openly supportive as Canon's, I think the influence of public forums like dvxuser has played a significant role in the development of the GH2 and the AF100 as well.

Speaking of the GH2, I'm wondering if anyone here has access to a GH2 as well as a hackable GH1? Now that we have Native 24p functioning reliably on the GH1, it would be interesting to see how the two cameras compare on a variety of subjects. Not so much to determine which camera is "better", but to evaluate which types of situations they are each well suited. Anyone else interested?
 
Cadence--
Looking at the countdown clock, you can tell from the cadence how close you are to the edge.
You get 1 group of three our four fast seconds, that's way in the safe zone.
After three or four groups of quick pulses, you are near the edge but still good. Faster than that, you run the risk of a crash.
With the Tiffen that lpowell recommended I was good to go!
I have both cams here lpowell, just let me know what you'd like and I'll run it.
 
Well had a test. 25p Transcend 16gb class 10 using 20mm pancake lense. shutter 50
Inside the house okay step outside in the garden (lotsa grass,trees etc) card write error almost instantly unable to read the corrupted files.

Going back to my previous settings. Thanks anyway Lpowell ;-)
 
mimirsan said:
I've been using this for quite a few months now

Avchd goes between 44mb-50mb in high details. It crashes instantly in 24p but super stable in 25p.

Native 24p/25p=Checked
Video Bitrate FHD/SH=50000000
Video Bitrate H=44000000
Video Bitrate L=32000000
Overall Bitrate=56000000

Why would it be unstable for 24p but stable for 25p?
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In my experience, AVCHD bitrates above 40Mbps require stablization tweaks in addition to the Video Bitrate settings. The settings above will produce videos with peak bitrates of 75Mbps. While I was able to obtain reliable results at this bitrate for 24p, 25p, 50p, and 60p videos (75Mbps GH1 Peak Performance Patch), it produced sporatic frame drop-outs when I attempted to make it work with the Native 24p patch.

I suspect the camera produces PAL 25p videos simply by cutting the 50p frame rate in half. On the NTSC side, 24p cannot be handled as a subset of 60p, and the 3:2 pulldown that interlaced 24p videos require complicates matters greatly. I've seen other clues that suggest 25p and 50p may need somewhat different optimizations that 24p and 60p, and will try to find time to do further tests this weekend.
 
mimirsan said:
Well had a test. 25p Transcend 16gb class 10 using 20mm pancake lense. shutter 50
Inside the house okay step outside in the garden (lotsa grass,trees etc) card write error almost instantly unable to read the corrupted files.

Going back to my previous settings. Thanks anyway Lpowell ;-)
Click to expand...

I am having a similar experience, though not as severe. This BP patch is no more stable for me than your reliable patch with 25pN enabled - perhaps even less stable actually. Both crash on foliage and deep focus. I think 25pN requires different treatment to 24pN. Theoretically I believe 25pN should be more stable, as there is no pulldown to perform, but it is still not stable in native with this patch. Sorry!

Bp Patch
25pN
1/50 sec
14-140 and FD 24mm f2 tested at f8
 
I was not able to crash it outside with the Tiffen Soft FX3 you suggested even with the shrub of doom at F11. Came close, the RT counter went into freefall, but then it slowed down again and kept recording.
Same shrub would crash it at 5 seconds every time w/out the filter.
 
DrDave said:
I was not able to crash it outside with the Tiffen Soft FX3 you suggested even with the shrub of doom at F11. Came close, the RT counter went into freefall, but then it slowed down again and kept recording.
Same shrub would crash it at 5 seconds every time w/out the filter.
Click to expand...

DrDave, what was the Bitrate of both those clips with and without the filter?. Thanks.
 
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I was getting 29-30 with the Tiffen filter, without the filter I have 12 files with a zero bytes file value--e.g., toast.
So I could maybe tomorrow (kinda dark now) run three seconds before it crashes and stop it.
I'm also going to try a Rock glass filter as soon as I can find the right thickness, because Barry wrote an article about how it improves the aliasing. But, hey, the Tiffen works great.
The main thing is, by watching the counter you can get an idea of how hard the encoder is working.
The Tiffen does add a kind of coating to the video, so for me it is a "keep it in the camera bag" item. I would imagine that it is very good for portraits, since that is what it is designed for. No one makes shrub filter, unless it is the Caprock.
http://www.caprockdev.com/antimoire.htm
These come in eight different strengths, so one could presumably find the lightest one that does the trick, and knock off the moire at the same time. They are a bit pricey, though.
 
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I was just thinking if it's worth trying a Tiffen one or two rather than a three which is stronger softness??

Yeah, i,ve been watching the ticker but not something i have time to do when i'm shooting the stuff i do. But the ticker changing should give lpowell a few more clues on what effect the hack is having on the camera.
 
first, thanks for this great settings, but I have a one problem with my GH1, the SH is perfect smooth, but FHD is not , I was trying a various shutters but still nothing, using sandisk extreme HD video 20MB/s, lumix G vario 14-42mm lens, Any idea why ? thanks for answer.
 
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DrDave said:
With the Tiffen that lpowell recommended I was good to go!
I have both cams here lpowell, just let me know what you'd like and I'll run it.
Click to expand...
Great, if you have a hi-res printer, here's a link to a PDF of the ISO-12233 test chart:

http://www.google.com/url?sa=t&source=web&cd=2&ved=0CCMQFjAB&url=http%3A%2F%2Fwww.graphics.cornell.edu%2F~westin%2Fmisc%2FISO_12233-reschart.pdf&rct=j&q=ISO-12233&ei=k16XTcHFJPLPiAKIzJydCQ&usg=AFQjCNGKvNbdr7tG-1KeKhqVfsbiEijCVQ&sig2=xY4tS8Q-b1OT7uuC8FyjJw&cad=rja

It would be interesting to see frame grabs of this chart both with and without the Tiffen filter in GH1 and GH2 1080p24 modes. Most printers will blur the finest lines on this chart, but those aren't needed to test the video resolution of the camera. Professionally rendered charts are available from Imatest, but they cost around $250.

For a real-life image quality test, I'd suggest a nature shot such as this:
http://vimeo.com/18902114

This type of scene is good for evaluating dark image details:
http://img835.imageshack.us/img835/4250/darkcryptavchdfhd.jpg

And here is a link to the killer chart for aliasing artifacts:
http://www.bealecorner.org/red/test-patterns/Zone720-sine-g22-b.png
 
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Here are frame grabs of a bullseye resolution chart I printed on photographic glossy stock using a Canon Pixma i8500 printer. I set up the GH1 with a Leicasonic 14-50mm lens @ 45mm on a horizontal tripod, illuminated the chart in indirect sunlight, and exposed it at ISO100, f5.6, 1/500 second. I took videos in all three resolutions: FHD 1920x1080, SH 1280x720, and HD 1920x720. I then captured screen shots at 100% and imported them into Photoshop. Using bicubic interpolation, I uprezzed the HD and SH frame grabs to 1920x1080. I then cropped out the upper left quadrant and saved the three images as JPEG's, Photoshop Quality Level 12. Here are the results:

BullseyeULC-FHD1920x1080.JPG
bullseyeulcfhd1920x1080.jpg


BullseyeULC-HD1920x720.JPG
bullseyeulchd1920x720.jpg


BullseyeULC-SH1280x720.JPG
bullseyeulcsh1280x720.jpg

 
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Amazing--do you have a link for the Bullseye chart as well, I can print one and compare the GH2
What a great lens/cam combo.
 
Post that in the Canon thread ...hahaha That is an very nice combo.

Love the smooth look of the Motion Jpeg HD mode. How does that appear in a real life shot?
 
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Late to the party again, but I have to say bravo and thanks, etc, for these outstanding hack setting efforts.
 
thank you gentlemen for your awesome work!:] any chance of you guys releasing a version that's specifically optimized for a native 25p? (pretty please)
 
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