Adjusting the image attributes

The Camera Raw dialog box lets you change the image settings for the target color space profile, bit depth, pixel size for opening the image, and resolution using the following controls:
Space
Specifies the target color space profile. Generally, this should be set to the same value as your Photoshop RGB working space. Keep in mind that the source profile for camera raw image files is usually the camera-native color space. (Higher-end cameras let you select a color space like Adobe RGB for the color profile when photographing.) The profiles listed in the Space menu are built into the Photoshop Camera Raw plug-in. If you want to use a color space that's not listed in the Space menu, choose ProPhoto RGB, and then convert to the working space of your choice when the file opens in Photoshop.
Depth
Specifies whether the image opens as 8 or 16 bits per channel in Photoshop. In ImageReady, 8 bits per channel is the only option.
Size
Specifies the pixel size at which to open the image. The default for this setting is the pixel size you used to photograph the image. Use the Size menu if you want to resample the image to a larger or smaller size.
• For square-pixel cameras, the Size menu is mostly a convenience for the user. However, choosing a smaller-than-native size is useful to speed processing when you are planning a smaller final image anyway. Picking a larger size is similar to upsampling in Photoshop.
• For non-square pixel cameras, the native size is the one that most closely preserves the total pixel count. This means the pixels in one dimension will be upsampled, while in the other dimension they will be downsampled. Choosing the next size larger than the native size keeps the pixel count along the high-resolution dimension constant, while upsampling the lower-resolution dimension to create square pixels. This larger size preserves maximum detail for non-square pixel cameras, since neither dimension is downsampled.
Note: You can always change the pixel size of the image after it opens in Photoshop.
Resolution
Specifies the printing resolution the image will be printed at or the amount of data in the image. This setting does not affect the actual pixels (pixel size of the image). For example, a 2048 x 1536 pixel image prints at approximately 28 1/2 x 21 1/4 inches at 72 dpi. When the resolution is changed to 300 dpi, the same image prints at approximately 6 3/4 x 5 1/8 inches. Resolution can also be adjusted in Photoshop using the Image Size command.