F-stop choice and the benefits of metadata review

Walk Like An Egyptian. Canyonlands NP, Utah, 2013

Yesterday I posted a photograph which was actually a collection of images that created sort of a loose story line which I called “Shadow Play”. The above photograph is one of the individual photographs from that collection–and I’m going to make an example out of it! You see, as I was looking at the metadata of this and all the other shadow images I noticed something: they were all shot at f/16.

Like a lot of folks who shoot landscapes, I typically use aperture priority mode so that I can pick the aperture based on the depth-of-field (DOF) I am looking for in any given situation. I let the camera pick the corresponding shutter speed for me (and since I’m usually on a tripod, the shutter speed is of no real concern). If I want a narrow DOF, I use a larger aperture (smaller number) like f/2.8 for example. For deeper DOF, I use a smaller aperture (larger number) such as f/16 or f/22. I am also conscious that above a certain f-stop, say, f/8, f/11 or f/16 (depends on the lens) diffraction sets in and the light bends a bit going through the aperture thus reducing the sharpness of the image ever so slightly…so I try to avoid those smaller apertures (bigger numbers) unless I think it necessary.

Now, back to the shadow images. Why did I choose f/16? If you look at the pictures, you’ll notice that the subject matter (a rock wall with a shadow cast upon it) is basically flat and in plane with the camera sensor. The DOF required to get everything in focus in these shots was minimal. I could have just as easily shot at good ole, tried-and-true f/8, or even f/5.6, and gotten everything in focus, avoided any diffraction issues, and been in the “sweet spot” for the lens in question. So again, why did I choose F/16?

The answer: I didn’t. I just wasn’t thinking. I had f/16 set in the camera from a previous setup that required more depth-of-field. I just forgot to change it for the shadow series of images. Aaaarrrggh!

The big lesson for me–other than the big one of always “preflighting” my camera before each shot or set of shots–is that studying your metadata trends on a regular basis can be very helpful. You can ask yourself why you choose certain f-stops…or lenses…or ISOs…or focal lengths on the zoom. You can start to see patterns…sometimes patterns of stupidity (like my example of the shadows shot at f/16) and sometimes patterns of lucidity when you make all the right choices for the situation. You can start to make more intelligent decisions about the most effective way to use your camera.