Operation Manual

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Editing photos
Last updated 9/13/2015
5 For Resolution, enter a new value. If desired, choose a new unit of measurement, and then click OK.
To return to the original values displayed in the Image Size dialog box, use Alt (Option in Mac OS) + click Reset.
Resample an image
Changing the pixel dimensions of an image is called resampling. Resampling affects not only the size of an image
onscreen, but also its image quality and its printed output—either its printed dimensions or its image resolution.
Resampling can degrade image quality. When you downsample, meaning that you decrease the number of pixels in
your image, information is removed from the image. When you upsample, or increase the number of pixels in your
image, new pixels are added based on the color values of existing pixels, and the image loses some detail and sharpness.
To avoid the need for upsampling, scan or create the image at the resolution required for your printer or output device.
If you want to preview the effects of changing pixel dimensions onscreen or print proofs at different resolutions,
resample a duplicate of your file.
A Image downsampled B Original image C Image upsampled
If you’re preparing images for the web, it’s useful to specify image size in terms of the pixel dimensions.
1 Choose Image > Resize > Image Size.