Avoiding Mud artefacts

Old ground here, but thanks for the post. Indeed, I am surprise mud happens at all there, since the test was done at 720p where mud is less of an issue. In the motion blurred 2nd shot (of the car park) I don't think that has any mud at all.
 
Old battle ground ;)
In fact, the first time I noticed mud in 720p was in a high shutter speed shot, that's the reason I began testing it. And yes, the 2nd car park shot is mud free :)
 
I know we are in danger of repeating A LOT of rather old ground here but in doing your test in 720p this has actually...possibly...maybe... just given us some new info to go off, because it's noticeable that on the frames from the slow shutter shots the mud is hardly noticeable (like the stars in the daytime, as you put it!), whilst I found back in Taiwan with my original mud tests in full HD mode when mud occurs it rips apart motion blur too, low or high shutter, and not just fine detail.

Could it be that the lower demands of 720p on the codec and image processor results in a cleaner motion blur?

Swing 720p through the codec with a fast shutter = mud.
Push 1080 through the codec with a fast or slow shutter = mud.
Coax 720p through the codec with a slow shutter = a way to avoid mud completely?

AVCHD 720p at 1/30 is how I intend to shoot from now on.

We know the rest... we know MJPEG 720p doesn't suffer. But it takes up loads of room, is just 30p and seems a little undersaturated & oversharpened to my eyes.

But your test at 1/30 720p AVCHD and the 30fps MJPEG mode does prove that the sensor & GPU are powerful enough to get a clean 720p image out of the camera and into our hands, at lower shutter speeds, even if the AVCHD codec fails us sometimes.

As said many times before, it needs B Frames.
 
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commanderspike said:
whilst I found back in Taiwan with my original mud tests in full HD mode when mud occurs it rips apart motion blur too, low or high shutter, and not just fine detail.
Click to expand...

The motion blur getting "ripped apart" - wasn't that due to incorrect pulldown removal in 60i/24p? I remember seen frame grabs that were obviously made up from two fields and they looking indeed 'ripped'. I see nothing like that when getting 'mud' at fast 1080/25p pans with 1/50 shutter. In playback it's really not that blatantly obvious while not good.

Short shutter speeds are however a certain way to break the encoding - but then again they risk break all subsequent interframe encoding as well and sadly that's how everything is shown now except in cinemas. I've seen sections of "28 Days Later" look horribly pixelated in broadcast. That's why from day one I've been really arguing the need of using external NDs to keep shutter speed at 1/50 PAL - 1/60 NTSC. BTW a quick pan at 1/500 will be pretty harsh looking even when shoot on film. A cool effect for certain occasions yes, but shoot like that through a whole film and audience will have epileptic fits. I will get migraine for sure :)

However I agree once again that PAL models should get 25 fps MJPEG! And a higher bitrate should be added for AVCHD!
 
1/30? At 60p that will cause you problems with double frames, and you will not easily be able to do reverse telecine to 24p. I'd recommend 1/60.
 
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