Scan your graph and save it in a supported image format (e.g. gif, tiff, png, bmp...), or copy it into the clipboard.
Load the graph into DigitizeIt: File->Open
or paste a graph via the clipboard (Edit->Paste Graph). You can also take a screenshot (Edit->Capture
Screenshot).
Tip: scan your graph at a reasonable
resolution, 1000 x 1000 pixels is usually enough
Zoom the graph to your liking with View->Zoom in
Put the axes:
a) select Axis->X min
b) now click on the lower value of the x-axis
c) enter corresponding x-axis value
repeat this for X max, Y min, Y max
Select linear, logarithmic or reciprocal scaling: Axis->x Scale->logarithmic
Now you are ready to go, after Data->Take
points start selecting points by clicking on the screen.
You can also let DigitizeIt automatically digitize line or
scatter plots for you. Select Auto->Find Line
or Auto->Find Symbol and click on the
desired line or one of the symbols, see also line
digitizing and symbol digitizing.
Choose, if you want the data sorted Data Set->Sort
The rest should be self-explanatory, when you are done save the data in ASCII-format with File->Export ASCII or copy the data to the clipboard (Edit->Copy to Clipboard). Now the data can be pasted or loaded in many other applications.