How to increase or decrease image resolution
01 Go to Image Size
The best time to resize a photograph is when you’ve finished editing it, but before you’ve sharpened it. At this stage, go to Image> Image Size.
02 Tick the right boxes
In order to resize your image without stretching or squashing it, make sure that the ‘Constrain Proportions’ and ‘Resample Image’ boxes are both ticked.
To increase/decrease size, type new numbers in one of the first four boxes. Here the width of the image is increased from 3,000-6,000 pixels; the other figures will adjust automatically.
04 Adjust to paper size
For a big blow-up, using the Document Size boxes can be useful. To create a 30×20-inch print, the Height is adjusted to 20 inches with a Resolution of 300 pixels/inch.
05 Web posting
For using images on the web on in email, you often need to decrease the file size. Changing the Pixel Dimensions enables you do this with ease. Here the Width is adjusted to 1,000 pixels.
06 Save for Web
For downsizing images for screen use, Photoshop’s Save for Web option can be useful because it enables you to have more control over the final result and previews the effect.
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