Adobe photoshop cs2 사용자 설명서
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ADOBE PHOTOSHOP CS2
User Guide
Greater bit depth (more bits of information per pixel) means more available colors and more accurate color repre
sentation in the digital image. For example, a pixel with a bit depth of 1 has two possible values: black and white. A
pixel with a bit depth of 8 has 2
sentation in the digital image. For example, a pixel with a bit depth of 1 has two possible values: black and white. A
pixel with a bit depth of 8 has 2
8
, or 256, possible values. And a pixel with a bit depth of 24 has 2
24
, or roughly 16
million, possible values. Common values for bit depth range from 1 to 64 bits per pixel.
A
B
C
D
Pixel depth
A. 1-bit (Bitmap) B. 8-bit (Grayscale) C. 8-bit (Indexed Color) D. 24-bit (RGB)
A. 1-bit (Bitmap) B. 8-bit (Grayscale) C. 8-bit (Indexed Color) D. 24-bit (RGB)
In most cases, Lab, RGB, grayscale, and CMYK images contain 8 bits of data per color channel. This translates to a
24-bit Lab bit depth (8 bits x 3 channels), a 24-bit RGB bit depth (8 bits x 3 channels), an 8-bit grayscale bit depth (8
bits x 1 channel), and a 32-bit CMYK bit depth (8 bits x 4 channels). Photoshop can also work with Lab, RGB, CMYK,
multichannel, and grayscale images that contain 16 bits of data per color channel. Additionally, Photoshop can work
with RGB and grayscale images that contain 32 bits of data per color channel.
24-bit Lab bit depth (8 bits x 3 channels), a 24-bit RGB bit depth (8 bits x 3 channels), an 8-bit grayscale bit depth (8
bits x 1 channel), and a 32-bit CMYK bit depth (8 bits x 4 channels). Photoshop can also work with Lab, RGB, CMYK,
multichannel, and grayscale images that contain 16 bits of data per color channel. Additionally, Photoshop can work
with RGB and grayscale images that contain 32 bits of data per color channel.
See also
Converting between bit depths
A 16- or 32-bits-per-channel image provides finer distinctions in color (but larger file size) than an 8-bits-per-
channel version of the same image.
channel version of the same image.
Photoshop provides the following support for working with 16-bits-per-channel images:
•
All tools in the toolbox, except the Art History Brush tool, can be used with 16-bits-per-channel images.
•
All color and tonal adjustment commands, except Variations, are available.
•
You can work with layers, including adjustment layers, in 16-bits-per-channel images.
•
Some filters, including Liquify, can be used with 16-bits-per-channel images.
To take advantage of certain Photoshop features, such as Extract, Pattern Maker, and some filters, you can convert a
16-bits-per-channel image to an 8-bits-per-channel image. It’s best if you do a Save As and convert a copy of the
image file so the original file retains the full 16-bits-per-channel image data.
16-bits-per-channel image to an 8-bits-per-channel image. It’s best if you do a Save As and convert a copy of the
image file so the original file retains the full 16-bits-per-channel image data.
Photoshop provides the following support for working with 32-bits-per-channel images: