I will check it tomorrow, I guess it will be worse... even C settings have the problem.
40Mbps AVCHD High Reliability Patch
- Thread starter Lpowell
- Start date
I will check it tomorrow, I guess it will be worse... even C settings have the problem.
I'm pretty sure that's just normal. You'll get varied responses here, anything from "More light, duh!" to "You should be able to film a scene like that except the GH1 just has issues with FPN/banding, etc."
Look up those terms on the GH1 forum and you'll see what I mean. It's been covered many times.
Look up those terms on the GH1 forum and you'll see what I mean. It's been covered many times.
First up the kit lense is crap indoors... do you have i exposure on? This is not a codec issue...hacked or unhacked as I can do shots pretty much like what your going for this is a exposure issue...MJPEG & AVCHD handle exposures differently.
What shutter speed you using and what aperture?
What you want and what a 600 dollar camera can deliver are two different things. There are limits to what the hack and this camera can do.
Can someone explain to me what the values in preset bitrates correlate too? and why drop it down to 180 instead of the opposite? Just trying to understand it abit more.
I have been trying to figure out a good setting for 720 at 1/30th shutter that keeps full bitrate and not freeze on pappas chart of death because I find myself shooting alot in low light but want to keep as much bitrate as possible. 32Mbit is the highest I have gotten without it freezing. What I have discovered is if you go over 34Mbit when shooting in 720 1/30th it does not freeze because it drops something cronic to 3Mbits and it only happens in 720. It does the same for this new setting also. The only workaround I can think of is to set FHD/SH to this stable 40Mbit and then H to the workable 30-34Mbit for 1/30th 720 stuff.
Thanks again Ipowell for the time put into this setup.
I have been trying to figure out a good setting for 720 at 1/30th shutter that keeps full bitrate and not freeze on pappas chart of death because I find myself shooting alot in low light but want to keep as much bitrate as possible. 32Mbit is the highest I have gotten without it freezing. What I have discovered is if you go over 34Mbit when shooting in 720 1/30th it does not freeze because it drops something cronic to 3Mbits and it only happens in 720. It does the same for this new setting also. The only workaround I can think of is to set FHD/SH to this stable 40Mbit and then H to the workable 30-34Mbit for 1/30th 720 stuff.
Thanks again Ipowell for the time put into this setup.
Its working for me ,thanks ipowell!
The Preset Bitrates determine the bitrate of the initial frame of each video. When using a Lumix stabilized auto-focus lens, the camera's processor has a lot to take care of at the very beginning of a video. I found that lowering the Preset Bitrate gives the camera a healthier safety margin to guard against occasional failures to start recording.
Park Edwards
Veteran
hey everyone, i know this statement can be filed under "duh", but do not shoot 720p using these settings with a shutter speed under 60. it just destroys the codec.
kainekainekaine
Well-known member
Is there any way to fix this?
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Stay tuned, I'm working on something optimized for that.
kainekainekaine
Well-known member
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I haven't tried these settings, but I've been able to generate posterization with the GH1 easily with any AVCHD setting - stock or hacked. It is easiest to find it in the shadows because more information is "tossed out" in the shadows because the eye is less sensitive to it. I'm pretty sure it is an inherent limitation in the codec.
The two best solutions seem to be
a) use a higher ISO. The extra noise tends to dither the posterization bands a bit.
b) Shoot MJPEG at a higher hacked rate. Of course, this is not good for long format, you can't play the files back in-camera if you've upped the rate significantly, and you are limited to 720P @30 fps. But the posterization is almost eliminated with MJPEG.
Spectra
Active member
I have found that conversion of the GH1 .mts files in Cineform Neoscene also helps improve the banding problems I have seen on GH1 video footage....especially gradients and banding in the sky....the interpolation of the 8-bit 4:2:0 chroma info to 10 Bit 4:2:2 Cineform codec seems to help in this regard.
I spent the whole sunday afternoon trying to find a stable setting that does not drop bitrate using the older 3.40dptools. My findings are
32 34 40 - Bsetting 30Mbit freeze at 1/30th
34 36 42 - 32Mbit no freeze at 1/30th
36 38 44 - 34Mbit freezing at 1/30th
Anything higher and bitrate drops down to 3Mbits. Only occurs for 720p
Freezing occurs on pappas chart of death with camera dead static. If the camera is slightly moving then it records but for how long I'm not sure. Keep in mind that at 1/30th it is usually low light shots with high details blurred in bokeh with iris fully opened so it would be a very rare case that you will be filming anything close to the sharp detail of pappas's chart.
I have had no problems shooting at 1/30th PAL, then again I am not a pro and not producing features =)
Looking forward to your testing Ipowell on this issue.
Something I've found with Pappas death chart, there are some settings that work if you start recording off the chart instead of just hitting start directly on it. I've found that if I tilt up off the chart, hit record and pan down to the chart that settings I thought weren't stable will often record fine.
It would be awesome to have settings that work perfectly on the chart, but at least for my shooting probably 99 percent of what I will be recording won't have that kind of complexity when I hit that record button. And if something does and it's simply a matter of having my hand in front of lens for a second then I can live that. And if you're shooting a film with a slate you'll probably have a less complex thing to start on anyway.
It would be awesome to have settings that work perfectly on the chart, but at least for my shooting probably 99 percent of what I will be recording won't have that kind of complexity when I hit that record button. And if something does and it's simply a matter of having my hand in front of lens for a second then I can live that. And if you're shooting a film with a slate you'll probably have a less complex thing to start on anyway.
your right Isaac.....at 1/30th it will be very rare for someone to be shooting a detailed scene as that in real life well lit and all in focus. I have been able to keep it recording by waving something infront at the start with hand held movements enough to keep it going but once i place it stationary it will stop. On B settings it has yet to freeze on me in all my real life low light 720 1/30th shots but it did so on the chart. Just waiting for someone to figure out how to set a minimum bitrate for VBR.
just to add on my test i was shooting with 20mm at f5 iso 320. So once again i don't think ill ever be shooting at f5 iso 320 at 1/30th. I should re do the test with realistic settings.
just to add on my test i was shooting with 20mm at f5 iso 320. So once again i don't think ill ever be shooting at f5 iso 320 at 1/30th. I should re do the test with realistic settings.
Why not? Why f1.7 or f11 and whatever ISO is more or less "realistic"? If you don't have much light, and want to achieve a little deeper DOF than at F1.7, the above settings seem quite right.
BTW, I am always using 1/30s shutter speed at low-light (instead of recommended 1/50s for PAL camera).
With the standard AVCHD recording modes, I suspect there's no reliable way to force high bitrates on low-light scenes that won't fail when confronted with well-lit, high-detail scenes. The AVCHD codec will inevitably reduce its bitrate when encoding dim and/or soft-focus image details.
In addition, the GH1's sensor gets pretty grungy in the dark end of its dynamic range. With a 1/30 sec shutter speed, random sensor noise will tend to get averaged out, but fixed pattern noise will be emphasized. Increasing the bitrate in this situation may only serve to enhance the details of the FPN, when what you really want is to dither down the posterization.
Also, please note, it's Lpowell, not Ipowell
