Try GNU Fortran. Eclipse IDE used to have Fortran hooks.

Your quality is going to depend upon your scanner to a large part. Jpeg is fine if your initial scan is good. Try using Vuescan software. It will allow you to adjust the brightness at the time of scan. This will reduce your detail loss better than any file format option. Next if things still seem to dark or washed out then I would suggest the software package LightZone not to be confused with LightRoom by Adobe. LightZone is free and has the ability to lighten and darken certain zones of light. I have had wonderful results with this software.