Nikon D300 User Manual page 59

File Naming
Photographs are saved using file names consisting of"DSC_" or, in
the case of images that use the Adobe RGB color space, "_DSC'_
followed by a four-digit number and a threeqetter extension (e.g.,
"DSC_O001 .JPG"). The [File naming] option is used to select three
letters to replace the "DSC" portion of the file name. For
information on editing file names, see steps 2 and 3 of "Renaming
Shooting Menu Banks" (pg. 256). Note that the portion of the
name that can be edited is a maximum of three characters long.
[] Extensions
The following extensions are used: ".NEF"for NEF(RAW) images, ".TIF"for
TIFF(RGB)images, ".JPG"for JPEGimages, and ".NDF" for dust off
reference data.
Image Quality
Choose image quality (pg. 56).
Image Size
Choose the size at which pictures are recorded (pg. 60).
JPEG Compression
Choose whether to compress JPEG images to a fixed size or to vary
file size for improved image quality (pg. 58).
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