V1.02
Thom Hogan’s Complete Guide to the Nikon D300
Page 245
When you select
Optimal quality
, the JPEG engine does
exactly what you expect. At
JPEG fine
,
JPEG normal
, and
JPEG basic
levels the EXPEED engine applies a fixed
compression level to the data and the file size will vary with
the amount of detail in the scene.
When you select
Size priority
, you’re telling the camera that
you always want the expected median file size
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for the JPEG
level you’ve selected. If you’ve set
JPEG fine
and
Size
priority
and the camera encounters a scene with more detail
than “normal,” it will increase the compression level from the
1:4 that
JPEG fine
normally uses. For the better JPEG quality
settings this generally isn’t a big issue, but if you’re setting
JPEG basic
and shooting lots of detail, you want to be
careful with setting
Size priority
as you will get a highly
compressed image with potentially visible JPEG artifacts.
Alternatively,
Image quality
can be set by holding down the
QUAL
button and rotating the Rear Command dial;
Image
size
can be set by holding down the
QUAL
button and
rotating the Front Command dial. (Look at the Top LCD to see
what you’re setting.)
Top LCD:
Metering and Exposure
Cameras need some way to adjust the amount of light that
gets through to the digital imaging sensor. In very bright
scenes, for example, we may need to limit the total amount of
light or the time that the light hits the sensor. In dark scenes,
we may need to increase the total amount of light or time the
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Yet another thing that Nikon doesn’t tell us in their technical documents.
