I have a strange Photoshop issue. I have a file in 300dpi. When I save it as a gif or jpeg and then open that file, suddenly the file is in 72dpi. How come and how to get it in 300dpi?
All GIF files are always 72 pixels per inch. (Note: Forget the misleading and incorrect language scanner makers make; your images are measured in "pixels per inch," not "dots per inch.") The GIF standard does not permit saving a GIF image with any other resolution.
Your JPEGs are probably 72 pixels per inch because you are using Save for Web, which removes resolution information.
The question is, why is it a problem? If you are saving an image for the Web, the resolution makes no difference and is ignored. Only the *total number of pixels* matters. On the Web, a 320×200-pixel image at 72 pixels per inch is identical to a 320×200-pixel image at 300 pixels per inch, which is identical to a 320×200-pixel image at 6,000,000 pixels per inch.
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