DPI (Dots Per Inch) settings are only applicable when printing an image. DPI has no bearing on images destined for screen. DPI refers to the amount of ink dots/spots the press will place within an inch. Since no display on Earth uses ink, DPI is an incorrect term to use for anything related to display screens. Images which include text should be 400 DPI at the final size in the layout. Resolution and image size are inversely proportional to each other. Enlarge an image, the resolution decreases; reduce an image, the resolution increases. Example: a 2 x 2″ image at 300 DPI (acceptable) enlarged to 4 x 4″ has a new resolution of 150 DPI (unacceptable). So for a 300 dpi scanner, we should scan only at 300 or 150 or 100 or 75 or 60 or 50 dpi instead of "odd" fractional values like 80 or 120 dpi. A 600 dpi scanner offers more choices: 600, 300, 200, 150, 120, 100, 75, 60, 50 or 40 dpi. DPI is dots/pixels per inch. In most commercial film scanners, the scan size is often given as a DPI of a print size. So in your case if they really gave you 300 DPI then at the pixel resolution of the files you received, the print size would be 3.3x4.2 inches. So uhhh you got 2.4 MP scans which is pretty crap and well, useless for printing (4x6" at 100 dpi = 400 x 600 pixels). for example, when using an image as a wallpaper on a website, a scan at 4x6" at 100 dpi will become pixelated once stretched more than 600 px on the longest length. if the output size is increased, it will solve the problem + suggested dpi for web-ready files is 72-100 dpi 사실 전자기기의 화면에서는 해상도에 ppi ( Pixels per Inch) 단위를 쓴다. 단위 길이 (inch)당 최소 표현 단위 (dot, pixel) 개수라는 점에서 dpi와 구분없이 쓰기도 하나, 엄밀하게 따지면 약간의 차이는 있다. 모니터나 스마트폰에서의 한 픽셀 은 다양한 색을 나타낼 수 Pe72jmI.

200 dpi vs 300 dpi