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hisara
03-29-2008, 09:55 AM
If i scan A4 size white page with handwritten text to computer, how many megabytes is the file?

Scanner uses 1200x2400ppi and 48-bit color.

What is size if i use only greyscale?

trevor
03-29-2008, 10:06 AM
At 1200x2400 ppi, 48 bit color, the file is going to be huge. 1200 x 2400 = 2,880,000 pixels per square inch. An A4 sheet has about 96.7 square inches, so there are around 278 million pixels. Then multiply that by 48 bit color (48 bits=6 bytes of color per pixel) gets about 1.67 billion bytes. So, uncompressed, you'll have approximately 1.67 GB per image.

For reasonable file sizes, I'd advise 300 x 300 ppi, 8 bit color or 8 bit grayscale.

Trevor

styrafome
03-29-2008, 01:26 PM
The scanner specs are only what the scanner does in hardware. You can ignore that because you will set your file specs in the scan utility. Instead of driving the scanner to the max (16 bits per RGB channel for 48 bits per pixel) you should set it for 8-bit grayscale (only 8 bits per pixel). Second, you can crunch it down further by your choice of file format. If you choose uncompressed TIFF, the file will be the biggest it can be. Use compressed TIFF first, then after you edit it, save as a high-quality JPEG and it will probably be just a few hundred K in the end.