This is a list of commonly used Whole ISO settings, Whole Shutter Speeds, Whole F stops, and the hard to find in-between settings of third F-stops and half stops (when they are available.)
I often get questions asking, “What are (1/3) one third f-stops?”, “What are these numbers on my Shutter Speed dial?” or “Why are there all these extra F-stops?” “Why do my camera settings look different that in my textbook?” There are many online explanations for 1/2, 1/4 1/8 sec. and so on, but what about 1/3, 1/6, 1/10 sec. etc? Or, how about the F/ stops: F6.7, F9.5, F19 and so on? The 1/3 (one-third) stops and 1/2 (halves or half) stop settings are hard to locate online.
I’ve found that when photographers and students get to know these numbers, at least in part, then there are fewer exposure mistakes. I have used versions of this list for many years, and this is the result of research and refinement.
I have taken details for the fractional settings, one halves, and especially the one thirds, from many sources.
Most books and online sources agree on the whole shutter speed settings, and the whole aperture settings (‘F stop’ and ‘aperture’ are used interchangeably), but they often vary on some of the in-between numbers. Some camera manufacturers favor a group of settings over others, and sometimes they even disagree with some of their own published literature and camera manuals.
The list is pretty consistent with most sources of this kind of information.
How to use the lists:
- The columns are separate, and read up or down, not across from one to another.
- The shaded area contains the ‘Whole’ ISO Speed, ‘Whole’ Shutter Speed, or ‘Whole’ Aperture.
- The area to the right of the shaded ‘whole’ settings are the 1/3 or third stop numbers.
- The area to the left of the shaded ‘whole’ settings are the 1/2, or half stop settings.
- ISO values don’t come in halves.
There are a few information gaps where no one can agree (such as the ranges between 1/4 sec and 2 secs.) and I couldn’t find an aperture number between f45 and f64.
PERMISSIONS: You may this list use this for yourself, or your classes, and may copy it as long as you leave in the copyright info (as a courtesy, please). Please link back here to this page as the source, and so, don’t distribute the file on your own.
I hope you find it useful,
Open the full sized version then print it, or right click to save it.