Bit rate Vs. Sampling rate

[virendrakhanna]

Hi Friends,

 

I am not sure about is this right place to ask a simple (may be silly also...) question.

 

I am fighting between a lot of talk of higher bit rates that is 35 mbps,85 mbps and so on. list goes now 880 mbps where everybody seem to prefering for higer bit rate.

 

My question is does bit rate is playing important role in quality rather then sampling rate. People are not talking of 4:4:4 / 4:2:2 or even 4:2:0/4:1:1.

 

My feeling is sampling rate is important then bit rate for quality. Bit rate makes things faster but it is just a transfer rate, nothing with realtion to quality.

 

Please put light on this.

(I may be silly asking this question, but I am confused a lot)

 

Virendra Khanna

Cameraman

New Delhi

INDIA

[Ben Syverson]

If you're talking about compressed bitrate vs color sampling "rate," then it's truly apples and oranges.

 

You could have a terrible-looking 4:4:4 image if compressed down to 1 Mbps, and you can have an amazing 4:2:0 image at high bitrates, especially since we don't know what the frame size is. We could be talking about 4K or HD; who knows.

 

When it comes to bitrates, higher is generally better, but there is a point of diminishing returns. You need to test, test, test to figure out what that point is. If you're doing talking heads on a static background, you might find that 17-25 Mbps is fine. If you're shooting a surf movie, you might realize you need 100 Mbps or more. When quality is more important than price or time, you can always shoot a raw uncompressed format, such as 35mm film.

 

However, it's not clear from your question whether you're talking about acquisition or the bitrate / sampling scheme of your DI or transfer... Perhaps you can elaborate?