My buddy Mark nearly gave up on his telescope after a string of grainy shots. He spent one whole, frustrating night just taking pictures with the lens cap on, following some old forum advice about dark frames. When he finally subtracted them from his star trails, the change was shocking. All that messy color noise just vanished, leaving clean, deep black space behind the stars. He called me at dawn, completely wide awake and ranting about hidden signal data. It totally saved the hobby for him.