|What is a Good Digital File? Back
A good digital file, in Tif format, is a file that contains enough pixel information to render the image crisply at the required size. The size of the file and the quality of the captured image determine the quality of the output.
For crisp output, your original file should contain preferably 300 and at least 200 pixels per inch at final the output size. Files with 100-200 dots per inch at final output may be acceptable, but will not have the sharpness and detail of larger files. A lower dpi leads to soft edges and loss of detail which may be acceptable for some images.
Note: Simply enlarging an image file with a graphics program (PhotoShop, etc) does nothing to enhance output quality - the file should be initially created with the final output size the determining factor of file size.
As an example, if we want to print a giclee 8x10 inches, we need to create a file which is (8" x 200 pixels/inch) x (10" x 200 pixels/inch) = 1600 px by 2000 px.
The total number of pixels is 1600 x 2000 = 3,200,000.
Since each pixel contains one byte each of Red, Green and Blue, our uncompressed TIF file size is then 3,200,000 pixels x 3 bytes/pixel = 9.2 MB.
Note that 1 MB = 1024*1024 bytes = 1,048,576 bytes.
The table below shows the file sizes for various output sizes at 200 and 300 dpi:
||@ 300 dpi