How do you convert 72dpi to 400dpi without loosing quality of an image?

Answer:
Turn off Resample Image in Image Size dialog in Photoshop. This will freeze pixels in your image so you will work with existing pixels, and will not ruine details (pixelate) but physical width and height of image will change and you will have 6 time smaller image, for example before 20 x 20 inches will change to 4 x 4 or something like that.
Contributor: Savke
First answer by Savke. Last edit by Savke. Contributor trust: 28 [recommend contributor recommended]. Question popularity: 1 [recommend question].