A couple of cheap items can tell a great deal about an item in a photo. By placing these items in your camera bag (someone mentioned using a softside cooler), they will always be available. Good items to have are:
1. tape measure (doesn’t need to be too big) is good to use when photographing cuts or bruises on victims.
2. A couple of rulers. These are easier to tack up beside an object that is on a wall.
3. paper-cups and a marker. These are helpful in labeling items to make reference to them in a report (commonly seen with shell casings).
4. 3 X 5 blank index cards to label items when photographing.
5. 2 Cameras. You should never count on just one. If using a 35mm, only photograph one case per roll of film even if you only use a few of the exposures. One way to eliminate the waste of not using the whole roll, is to photo each item or area twice.