C300: C300 Mark II - Stay Away from 50Mbps

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mraaron895

Well-known member
Just a quick word of warning. When you set the Mark II's bit rate to 50Mbps you will encounter macro-blocking artifacts. It's most evident with fast camera movements or quick moving subjects. I switched into the higher bit-rate modes and found no macro-blocking.
 
Uhh...isn't that the same story with any 50Mbps camera, such as the C300 Mark I, which had image quality which tons of producers were fine with, despite macroblocking on fast camera movements and quick moving subjects? Or are you saying it's much worse than the 50Mbps on the C300 Mark I?
 
I never noticed any marco-blocking in the 3 years that I owned my C300 MK I. That was a well known AVCHD C100 issue. My guess is the amount of information being processed off the Mark II is too great for the standard 50Mpbs codec.
 
Which picture profile were you using? I imagine log2 would have significant trouble there, but rec709 profiles should be fine. I haven't even touched the proxy recording yet.
 
WDR. I don't see how applying a pic profile would cause macro-blocking. I can understand banding and noise issues though. Macro-blocking is a sign of poor image compression
 
You'll really notice it if your using a 360 degree shutter angle. The motion blur at a normal 180 degree shutter hides it.
 
I rarely use a 360 degree shutter angle.

I've been shooting Wide DR at 50 Mbps and I don't think I've noticed any significant macro-blocking. Perhaps some noise. Though, I also haven't edited any footage yet, just skimmed through some footage I've shot for others to edit.
 
360 deg shutter is a no fly or rarely fly zone. Motion rendering is very smeary depending on how much motion there is in the frame and generally the image can get pretty mushy unless its a talking head. One of the MAJOR bugs with the Mk2 is the camera defaulting to 360 shutter when changing capture settings, especially when shifting to higher frame rates. In my opinion, a camera SHOULD NOT make a shutter angle change on its own when changing a capture parameter . If you jump to 60P from 30P, you lose a stop of exposure and thats the way it is, I expect that. I don't need the f'ing camera trying to 'help me out' by jumping to 360 degree shutter to keep the exposure constant. I'd say stay away from 360 shutter because its likely that combined with the 50mbps codec that is giving you the macro blocking. The compression engine is likely suffering since the images coming at it are mush.
 
360 degree shutter use is quite common actually. Watch any music video with dancing or zombie flick and you'll see examples of it. I use it all the time on dance floors to accentuate people's movement.
 
mraaron895 said:
360 degree shutter use is quite common actually. Watch any music video with dancing or zombie flick and you'll see examples of it. I use it all the time on dance floors to accentuate people's movement.
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360 Deg. shutter certainly can be a creative choice for specific situations or a last ditch grab for the last F stop in a poor lighting situation. My point is that I don't want the camera making this creative choice for me and it seems that the Mk2 does just that with the present firmware in the camera.
 
mraaron895 said:
360 degree shutter use is quite common actually. Watch any music video with dancing or zombie flick and you'll see examples of it. I use it all the time on dance floors to accentuate people's movement.
Click to expand...

I think you're misinterpreting a 360 degree angle (which would be 1/25 shutter for 25fps), for dance scenes and zombie flicks usually use shorter shutter times like 1/100.
 
maarek said:
I think you're misinterpreting a 360 degree angle (which would be 1/25 shutter for 25fps), for dance scenes and zombie flicks usually use shorter shutter times like 1/100.
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No, no, no. 180 degree rule means the shutter speed is set to 1/180 which is so fast the shutter gets up to 180 degrees in heat. The faster the shutter speed the hotter it gets, just like a car.
 
Eric Coughlin said:
No, no, no. 180 degree rule means the shutter speed is set to 1/180 which is so fast the shutter gets up to 180 degrees in heat. The faster the shutter speed the hotter it gets, just like a car.
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Huh?

unless you are joking 180 degree shutter means the exposure time per frame = 50% of the frame rate. So if your frame rate is 24 , you already have 24 slices of time in 1 second . 180 degrees means each frame is getting exposed for 1/2 of the time (360 degrees would mean an exposure time equal to the frame rate). Picture the spinning mirror of a reflex film camera . Those mirrors were circular in nature and generally a half circle in shape (180 degrees) the purpose of the mirror was to allow through the lens viewing and cover the film plane after a frame was exposed and unexposed film was being pulled into the gate for the next exposure. Degrees of shutter is just another way of expressing exposure time per frame , same thing as 1/48, 1/60, 1/120 etc .
 
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