Mechanical vs. Electronic shutter and/or CMOS vs. CCD (or CMOS global)

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Mechanical shutter expose the full sensor (or film) at speeds below 1/250 sec. or so.
At higher speeds curtains are closer and do not expose the entire sensor to the light at the same time. It can cause rolling shutter at higher speeds because pixels are not all exposed to the light at the same time.

Common CMOS sensors capture light by their pixels, sequentially. It also could produce rolling shutter.

What is the advantage to use mechanical against electronic shutter to avoid rolling shutter?

Surely I am missing some explanation and/or I am misunderstanding some concepts

Please?
 
The solution with digital sensors is global readout. All the pixels are read simulateously and the data dumped as one frame. Would suprise me if the P4P didn't have a global sensor now, they are increasingly available and avoid the progressive read issue you undentified.
 
I believe when you trigger the mechanical shutter, say 1/200 to expose the entire frame, all pixels store their data at once and it is a slow storage process to do so.

A rolling shutter with video that scans a full frame in 1/10 second results in faster output for video since no storage buffer is needed to store all the pixel info at once and then release it as with the mechanical. Also, the FPS video speed is slower too which works in conjunction with the rolling shutter - but then you deal with the distortion off it too.

There is some talk with the P4 Pro doing some sort of scan line-skipping for the 120 FPS speed which may be due to the lower rolling shutter scan speed off it and the need for it to gain some storage speed. The Inspire 2 with the X5S and the $1000 license for the faster cinema speed might not be line skipping in 4K-5K mode as in the P4 Pro since it is using a faster video processor in the nose of the Inspire 2 as well as super-fast SSD storage both. I thought I read where a 40 minute 4 or 5K raw cinema video off the Inspire 2+X5S eats up almost a half a terabyte of storage so there is a lot of data coming into play for all that storage and speed, to say nothing for the editor''s scratch area to work with it all.

Or that's my two-cent theoretical explanation of it all, be it right or wrong.
 
I believe when you trigger the mechanical shutter, say 1/200 to expose the entire frame, all pixels store their data at once and it is a slow storage process to do so.

A rolling shutter with video that scans a full frame in 1/10 second results in faster output for video since no storage buffer is needed to store all the pixel info at once and then release it as with the mechanical. Also, the FPS video speed is slower too which works in conjunction with the rolling shutter - but then you deal with the distortion off it too.

There is some talk with the P4 Pro doing some sort of scan line-skipping for the 120 FPS speed which may be due to the lower rolling shutter scan speed off it and the need for it to gain some storage speed. The Inspire 2 with the X5S and the $1000 license for the faster cinema speed might not be line skipping in 4K-5K mode as in the P4 Pro since it is using a faster video processor in the nose of the Inspire 2 as well as super-fast SSD storage both. I thought I read where a 40 minute 4 or 5K raw cinema video off the Inspire 2+X5S eats up almost a half a terabyte of storage so there is a lot of data coming into play for all that storage and speed, to say nothing for the editor''s scratch area to work with it all.

Or that's my two-cent theoretical explanation of it all, be it right or wrong.
We don't need to theorise, manufacturers data sheets tell the global shutter (cmos) and what's possible story- speeds up to 13 microseconds- that's equivalent to 1/77000s shutter speed. Black magic are using global shutter cmos very effectively.
 
The solution with digital sensors is global readout. All the pixels are read simulateously and the data dumped as one frame. Would suprise me if the P4P didn't have a global sensor now, they are increasingly available and avoid the progressive read issue you undentified.
If P4P has a CMOS global sensor, what for mechanical shutter?
 

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