Anyone having card speed issues, please try again without native 24p

or can someone post a screen grab of the high detail scene they'r crashing on so i can get an idea.

I'll upload the chart for you.

Shoot the( Star Chart ) full frame from a high res computer monitor. I have always done that to spike a bit rate or do a quick tests for one reason or another. It will usually get you there within 90+ percent of a high detail scene without having to go out and film one every time you need to run a test.

Tip- when focusing on the star chart get the lines to a crispy jaggie dance. Also move the camera too in separate tests- to simulate change of scene doing circular motions as well swaying it, this will get the VBR going. Also if you shoot at 1600 ISO that also with push the bit rate even more when filming the star chart off a screen, and this will allow you to stop down the lens so you get very sharp performance out of the lens so it's as crisp as its gonna get. Extreme yes, and it ain't pretty, but it works for hitting the codec ceiling for testing


Drop it in quicktime etc, and play full screen- Then run the tests..

I also uploaded a picture so you know what I'm talking about. Don't use this one, as it's just a sample-
download the file I uploaded as that is at a 2K frame.

Here is a link to a file
http://www.sendspace.com/file/scn6oz

I just did a test moments ago on my 60-62-70 60i 24 wrapper on Class 10 extreme and got the error.


Could someone please run these numbers 54- 58- 68 and let me know how they compare in I/P frame performance wise against "C" settings & 60 - 62 -72?


Pappas
 

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alright..cool. i'll hook my netbook up to my tv. that's full 1080. Should work.


Just keep the ISO low and make sure the shots absolutely static.. just fill the screen with detail. Admittedly it's taken as much as just under a minute for it to happen to me on that chart, but I reiterate that my screens also not very high res.
 
Make sure it's in manual focus as well -- I found that it would hunt enough to prevent it from freezing. Also, in my case, I shot the carpet. Plenty of detail, no motion at all.
 
My 2 cents

I am facing selection of switching from PAL to NTSC due to travelling trip, so I did some testing for both system under “D” setting (50,56,60).

The camera works stable at PAL system even using class 4 SDHC, with selected native 25P, it created max bitrate at 65 and avg 43 at 1080p25 when shooting high detail and tsunami pan. The same scene under 720p50 mode, we have max 47 and avg 43 footage.

Switched to NTSC at the same “D” setting and native 24P, I obtained card write error under high detail scene with tsunami pan, daily normal shoot with steady shoot as well. Tested in class 4 only. It happened at FHD, SD, and even at 44,56,60.

I quickly go through this thread, most mentioned errors are under 24P situation. May I know is it so important to shoot 24P, how about shoot at 25P.
 
I quickly go through this thread, most mentioned errors are under 24P situation. May I know is it so important to shoot 24P, how about shoot at 25P.

Interesting. Is everyone who is getting this error shooting in NTSC? Might be another piece of the puzzle.
 
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Earlier I used "D" settings and Native 25p PAL. I often had card speed errors when zooming in and out (1080/25p and 720/50p). My camera also froze, after which I had to remove the battery and all the footage was lost (0 byte).

Now I have moved to "C" settings and 50i. I have received less speed errors (still get some if I start to zoom in-out like crazy) and even if I get one it does not freeze the camera, and the footage recorded up to that point is usable.

I am using an AData 16GB class6 card with write speed average 7-8MB/s. I studied the footage and found that indeed when I started zooming in-out and the camera stopped recording there were high spikes (350k I-frame) in the MTS file which the card sure couldn't handle. But even if the recording is stopped, for me it is a very important difference that the footage is not lost. I suspect (but cannot tell for sure) that the Native 25p messes up when there are speed errors while in 50i there is no such problem. I also haven't noticed any pulsing since I moved to "C" @ 50i.

So it seems that for these two reasons Native 25p is not the way to go at the moment.
 
I shoot Pal. No error with 24/25p native off switch native on and write error on static shots
Well, write speed errors are better than "freezing" that happens under NTSC mode. Can someone with PAL camera upload an EyeStream analysis screen of such a file?
 
my shots are on a PAL gh1 if that helps? thought they have yet to stop writing so it might be useless for what you are looking for.
 
I'll upload the chart for you.

Shoot the( Star Chart ) full frame from a high res computer monitor. I have always done that to spike a bit rate or do a quick tests for one reason or another. It will usually get you there within 90+ percent of a high detail scene without having to go out and film one every time you need to run a test.

Tip- when focusing on the star chart get the lines to a crispy jaggie dance. Also move the camera too in separate tests- to simulate change of scene doing circular motions as well swaying it, this will get the VBR going. Also if you shoot at 1600 ISO that also with push the bit rate even more when filming the star chart off a screen, and this will allow you to stop down the lens so you get very sharp performance out of the lens so it's as crisp as its gonna get. Extreme yes, and it ain't pretty, but it works for hitting the codec ceiling for testing


Drop it in quicktime etc, and play full screen- Then run the tests..

I also uploaded a picture so you know what I'm talking about. Don't use this one, as it's just a sample-
download the file I uploaded as that is at a 2K frame.

Pappas

I guess my laptop does not qualify as a high res monitor. I got lower bit rates using it and the "star chart" than for the back of the dollar bill. When using the dollar bill, make sure you are full frame on the detailed areas with no blank area in frame. This may not be possible with non-macro lenses.

I disagree with a few of Pappasarts suggestions.

Don't use High ISO. The added noise is largely random and probably has the same effect on the CODEC as a bit of motion. Use a low ISO and possibly increase the noise reduction setting.

Don't shoot at f/16. 4/3s lenses are typically sharpest around f/5.6. Legacy manual lenses are typically sharpest at around f/8. At f/10, diffraction noticably softens images from the GH1 sensor due to its small pixel pitch. F/11 and f/16 are nice options if you want to try to reduce image aliasing when shooting video precisly because these small apertures blur the image a bit.

Do make sure your target is completely in focus across the entire frame. That means make sure it is very parallel to the camera's sensor.

Do use the sharpest lens you have at its sharpest aperture. As mentioned before, that's probably f/4 to f/5.6. This also gives you a little bit more DoF than shooting wide open.
 
Raising the shutter speed to 1/500 or faster raises the amount of detail considerably - probably because it eliminates the effect of vibration, motion etc... It might easier for testing than trying to stabilize everything.

Chris
 
Raising the shutter speed to 1/500 or faster raises the amount of detail considerably - probably because it eliminates the effect of vibration, motion etc... It might easier for testing than trying to stabilize everything.

Chris
The GOP is ~15 frames, which at 24 fps works out to >1/2 sec time span between I frame and the last P frame in GOP. At faster shutter speeds Each P frame captures more detail, however there is still "overall" motion. Stabilizing on tripod eliminates overall motion as well. AVCHD encoder seems to have a "funky" relationship between I/P frame sizes, especially as you start pushing bitrates up. Throwing a native patch on top of this seems to complicate the relationship further (rogue P frames).
 
can you give me more details on setting, i want to duplicate any case possible to get a stable machine during my trip.

I use ptools recommended "c" settings. Very very stable for me using a sandisk class 10 and verbatim class 10. Without native 24/25p.

If I use same settings but with 24/25p ticked on I get write error on static shots. As mentioned before...seems to be a common problem with the 24/5p patch.
 
Earlier I used "D" settings and Native 25p PAL. I often had card speed errors when zooming in and out (1080/25p and 720/50p).

Now I have moved to "C" settings and 50i. I have received less speed errors (still get some if I start to zoom in-out like crazy)

high spikes (350k I-frame) in the MTS file which the card sure couldn't handle.



If I use same settings but with 24/25p ticked on I get write error on static shots. As mentioned before...seems to be a common problem with the 24/5p patch.



it's fine with my camera in highest details with 25p native, analysis from streameye listed pervious, what is the max and avg bitrates you guys obtained?

my setting are 50,56,60(D setting) what are yours?
 
Hi all. i've been having the freeze problem for some time now, but 60i is not an option for me. i don't have adequate software for pulldown.
my question is: will repeated freezing "battery pull" have any negative effect on my camera? if there's no danger. i'll have to learn to live with it :)
 
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