Scanning maps and GRASS

Casey Claiborne mskc at
Thu Nov 9 07:00:00 EST 1995

        I had wanted to ask you another question about the scanning:

At 12:15 PM 11/6/95 -0800, grassu-list at wrote:

>2) Scan the map at a resolution of at least 150 dpi and preferably 300 dpi.
>   This increases the accuracy of your registration and if you are going to
>   digitize anything after registration, it will increase the accuracy of
>   that, too. I store the scanned image as a tiff file.

I was speaking to a person who would be doing the scanning. He said
that he would use 75 dpi. I told him that it needed to at least be 150 or
300 (as given by your instructions) - he said that the computer screen
can only see the best at about 75 dpi and that to scan it any better
would just be overkill - I mentioned that it would be for a GIS system, and
he maintained that still 75 dpi would be enough. 

I wanted to know what you thought about it. Should I stamp my foot
down and say that I want 300 dpi?

Thank you in advance


One must note the importance of setting reasonable and achievable goals for
                    "If you aim for nothing, you'll hit it every time" 
                               -Theodore Roosevelt

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