Isolating a piece of equipment with GIMP

General
1
  • Use Foreground Select. Draw around the object, press Enter, then draw inside the object. You can keep drawing and refining.
  • Select → Invert to select the background
  • Can desaturate to make it pop
  • Tools → GEGL → Box Blur to blur out the background
  • Select → Save Selection to Channel for later use
2

I needed to reduce glare in an image.

GIMP → Colors → Shadows-Highlights

worked great. Colors → Exposure can work too.

3

Pulling an image out of a paper at high DPI

Use Inkscape. Import pdf using the built-in non-poppler, Ungroup, then select the image, file-> Export, Selection, set a high DPI.