oblique lighting

With the naked eye, evidence may not be visible. The simple technique of hold you flashlight to the side of an area you would like to examine could show you great evidence. This is a great technique for footprints and foot impressions.

Here’s a typical scenario: A patrolman responds to a burglary of a business or residence. The door has been kicked in. The patrolman looks around but doesn’t see any evidence to collect inside. Outside, there are some foot impressions in the snow or mud, but they lack enough detail to cast or photograph. The patrolman clears the scene with no evidence recovered.

Here’s the deal; oblique lighting can illuminate evidence that is not visible with the naked eye AND it requires little training. Can you turn a flashlight on? Great, you are half way there.

The technique is easy. I demonstrate the technique in the picture above. Turn the lights off and lay the flashlight along the floor or door.  this can pose a problem if you are outside, but it must be done.  I am crouched down looking for foot impressions or prints.  Even if you don;t find any evidence, it gives the victim the illusion that you know what you're doing!

The second picture I am standing and pointing the light right at the ground.  You are not going to discover any evidence this way.

Why is using oblique lighting important? Compare the following two photos. The same locations were photographed. Would you think that there was any usable evidence in picture 1? The second photo is using oblique lighting.

                                                                Ambient/Natural Lighting

                                                                         Oblique

NaturalLight                                                                                                 Oblique Light

What a difference huh? There may be great evidence that was missed or disturbed because you didn’t know how to locate it. Lifting and collecting that evidence is a whole different training. For this particular post, I wanted to post how to find it. If you work for an agency that has detectives or evidence techs that can be called, I would suggest that. If you ARE the detective or evidence tech, then read my later post. If the foot impressions are in snow, then you would still use the oblique lighting, but spray a light coat of spray paint into the impression to give it some contrast.


The oblique lighting technique works great for kicked in doors. Hold the light against the door and see what appears. Most guys will see the broken lock and never think to look for a foot print.
That's it for now.  Now go get those bad guys!
The footprint pictures were not taken by me, but by Rodney Schenck .Rodney A. Schenck