Why is Windows image Resolution not always same as Photoshop value for same file.

lakdiva  wrote If I create an image in PhotoShop Elements setting size and resolution and save it as a jpg file I can look at the resolution using Windows file details by selecting to display horizontal resolution. PhotoShop element writes out dpi to the header of the image file. If I take an image from say a camera, modify the dpi to match the coin I have photographed and save the file Photoshop does not always save the new dpi to header of image file. It writes to some Meta data since it knows the value when I open the file with photoshop. How do I get photoshop to update the dpi recorded in header without needing to create a new blank image with required resolution and copying camera image to new file. Thanks for any advice

Menu Image >> Image Size

Uncheck resample if you want to keep the original size in pixels (only way not to lose quality)

Enter your new ppi resolution (pixel per inch, not dpi, dot per inch is a property of the printer)

You'll see the new size in inches corresponding to the new resolution.

Save over your original or create a new version (copy).

The only meaningful size of a digital image is in pixels.

The resolution or physical size in inches are up to you to choose. If you keep the pixels size, the resolution will be calculated from the chosen inch size, or the inch size will be calculated from the resolution.

Note that if you save your new resolution image over the original by resampling, you'll lose quality.

If you save over without resampling, you also theroreticall lose quality when saving in jpeg format (lossy compression issue) but that may be negligible.

Moving to Photoshop Elements