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Type 7 as the number of inches in the Width field of the Document Size section.

Note that the height automatically changes to 5.25 inches if the Constrain Proportions check box is selected. With these new dimensions, the linear resolution now reads 365.714, which is a good result for printing at higher resolutions — much sharper.

You have changed the dimensions of the image from 35 x 26 inches to approximately 5 x 7 inches without altering the number of pixels — so no interpolation has occurred. The dimensions of the pixels themselves have changed — from 1/72 to 1/365 of an inch, and that's how the dimensions of the whole image have been so drastically reduced. (To see the differences in pixel dimensions, compare the two samples on the next page — a section of the original image at 72 ppi and the same section at 365 ppi.)

Taz's Take: You can just leave the image as is, with an appropriately stunning resolution of 365.714. If you'd like to see how to change the linear resolution using resampling, rather than by changing the image dimensions, continue with Step 7.

Adjusting the linear resolution without resampling the image will not change the pixel data in the image, just the dimensions of the pixels and therefore the overall dimensions of the image. Whenever you check the Resample Image check box, and make an adjustment to either the linear resolution or any of the image dimension values, you will be introducing image interpolation that will alter the pixel data and typically soften the image and reduce the image's clarity. So, if your target linear resolution is 300ppi (the standard requested resolution for commercial printing), and your non-resampled image resolution is close to 300ppi (as the 365ppi is here), you should typically just let the linear resolution stand. If your non-resampled resolution rises above 400ppi, though, you might want to consider resampling down to 300ppi.

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