How to convert dots per inch to pixels per inch

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A publisher is asking for tiff files at 300 dpi (dots per inch). What resolution is this in pixels per inch? Is there a formula?

-- Jon Remmerde (remmerde@bendnet.com), June 15, 2000

Answers

With publishers, DPI and PPI are probably used interchangeably. They usually want a 300PPI file because they'll probably be printing it on a 2400 DPI imagesetter. Check with them, but that's my guess.

It's a bit different when you're rendering your own images because with a dot matrix printer you may have 1440 DPI, but you probably want somewhere between 100 and 300PPI to get the image size and quality you want. In books and magazines they usually want a good 300PPI.

Good Luck.

-- Gerald M. Payne (gmp@francomm.com), June 16, 2000.


Jon, Gerald is correct. Somewhere along the digital line everyone started referring to image resolution in dots per inch when in reality there are no dots/inch. Dots per inch is a printer reference relating to putting ink on paper. Screen image resolution is always pixels per inch.

-- fred (fdeaton@hiwaay.net), June 16, 2000.

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