"MrB" <com> writes:
Probably not as well as it's explained in the manual, but here's a
summary. Image quality depends on the compression of the file. Compression
is "lossy" -- this means that details are lost in a compressed image.
NEF : 12-bit data saved directly to memory. Any compression is lossless.
JPEG Fine : Compression is low -- 1:4
JPEG Normal : Compression is medium -- 1:8
JPEG Basic : Compression is high -- 1:16
The ratios tell you that with low compression, the compressed image is 1/4
or 1/8 or 1/16 of the original file size. Some details are lost, as the
compression assumes similar bits are the same. Sometimes this results in
'banding' or posterization or the like. Often the compressed image can't be
distinguished from the original.
The size of the image is the dimensions in pixels. Large images are 3,008
pixels wide by 2,000 pixels high. Medium images are 2,240 x 1,488, and
small are 1,504 x 1,000.
A confusing issue is that 'file size' may refer to bits (the number of bits
in a file, which is one issue with compression) or to dimensions (the
number of pixels, and compression is irrelevant). I may have a LARGE image
size in dimensions at HIGH compression. If you have the English manual, see
pages 41 through 44. Other manuals will have the same explanation on some
For more detailed explanations of image size and dimensions (dimension is
often referred to as 'resolution'), see
(several pages, but worth the clicks; ignore the use of 'effect' for
Phil Stripling | email to the replyto address is presumed
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