Moon Maid's sensor comparison (PART 2)

Started Mar 1, 2012 | Discussions thread
DSPographer Senior Member • Posts: 2,464
Re: Additional "downsampled" SNR curves for D800

Marianne Oelund wrote:

Absolutic wrote:

These Nikon D800 developers suggest shooting at Medium size (appx. 20MP) claiming it is a healthy equilibrium, in terms of general shooting. . . . Do you happen to also have charts for 20MP medium size?

Since there is a rather large number of size selections available from the camera (not to mention all the ratios you can use in post), here is a procedure for you to arrive at the SNR curve for any downsampling ratio:

d = 10 * LOG(36/n), where
d is the number of decibels to add to the D800 full-resolution SNR curve,
n is the number of megapixels you are downsampling to,
and LOG is base 10 logarithm (not natural logarithm).

This is correct if the noise is uncorrelated. This is the typical case, but fails for pattern noise and data that has been filtered to suppress noise. Examining the spatial frequency content of the noise can help identify these two cases.

 DSPographer's gear list:DSPographer's gear list
Canon PowerShot G7 X Canon EOS 5D Mark II Canon EF 24mm f/2.8 Canon EF 50mm f/1.8 II Canon EF 200mm f/2.8L II USM +4 more
Post (hide subjects) Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow