Grey Skies, so a little HDD cleansing!

[CKemu]

My telescope has been cleaned, my kit organised, cables de-knotted, notes made and recent photos processed. I've added a white light filter to my wishlist and upgraded my processing tools to include Lightroom 4.

As a photographer I take a lot of photos, and LR4 is making me seriously consider doing a better job with my organisation, folder structures and keywording. I have around 2.4TB's worth of images, of which 382GB are under the /astrophotography/ subsection.

I've decided that I need to delete un-used images from photoshoots etc and be less clingy to photos. I'm going to keyword and tag dark images with data like temperature, keyword with objects like M42 etc, but I am wondering by what "method" do you the forum members go about deciding what images to keep and what images to remove.

Sure I have 6TB's worth of HDD space, but unless the Moon became volcanically active or Coke put a neon sign on the Moon, the Moon is going to stay the same of the foreseeable future!