Resolution

Resolution

Q1:	Is it possible to figure out how big a file will be before I scan anything? I need to scan a bunch of photos, but I'm a little worried that I'll run out of storage space. Is there a way to figure out how big of a file size that a scanned image will create before actually scanning it?
A1:	You can use the New command under the File menu to do some calculations for you. In the appropriate fields, just enter the Width and Height of the image and what Resolution you'll be using for scanning. Also indicate the mode (Grayscale, RGB, or CMYK). The size will change to indicate the approximate file size based on the settings you enter. This will not be the final number, as other factors such as file format will determine the final size, but at least you'll get a good idea of how big each scan will be.
Q2:	What is optical resolution?
A2:	Optical resolution is the "true" resolution of a scanner. Often scanners will list the resolution as 800x1200, but in smaller print it will say "600x800 Optical." A scanner's top resolution at best quality is determined by its optical resolution. Any higher numbers are achieved through interpolation, where software is used to "invent" extra pixelstherefore the quality will not be as good. In general, the higher the optical resolution, the better.
Q3:	What is the best resolution for printing on an inkjet? At what resolution should I scan if I'm going to be printing it on my inkjet printer? (My inkjet is set to 1440 dpi.)
A3:	The resolution of your printer (in this case 1440 dpi) should not have any real influence on your choice for the resolution of your scan. The best thing to do is to perform a test on your specific printer to determine the ideal resolution. Take an image with some fine details (not a cloudy sky) and scan a small portion of it at various resolutions75 ppi, 100 ppi, 125 ppi, 150 ppi, 175 ppi, etc. Don't go any higher than 300 ppi. Save them each and place them all into a page-layout program. Print the page and then compare the quality. What you should see is a "cut-off point," where higher resolution does not result in better quality. Often it is around 125175 ppi. Use that as the "target" resolution for your printer. Note: That does not necessarily mean you should scan at that target number, but that you should end up at that number.