Beautiful diagram of basic manual photo principles.
These are numbers every photographer need to know! Memorizing these numbers and knowing how they interact with each other will allow you to grab the best image possible in any situation!
In a nutshell; to keep the same exposure when changing settings, raise or lower one of the three main photo elements (Aperture, Shutter Speed, ISO) opposite of the changes you made after achieving a correct exposure. For example, you take a photo with these settings: F/Stop 5.6, Shutter Speed 60, ISO 400. The result is a correctly exposed, but you would like a more shallow depth of field. To get the desired depth of field you lower your aperture two full F/Stops, to compensate for the additional light entering the camera you must set your shutter speed two steps higher, lower your ISO by two full settings, or change shutter and ISO by one full setting. Each of these three changes should technically give your the same amount of light entering your camera as the settings you started with.
Most digital cameras allow you to raise or lower each of these settings in 1/2 or 1/3 increments, so make sure you know how your camera is set. Moving from F/5 to F/5.6 is not one full F/Stop!
I’ll use this graphic I saw on PetaPixel without a doubt time I teach a workshop! The only thing I would change is the ISO bar. Both the shutter and the F/Stop bar will give your more light as you move your setting to the left and less as you move right, but the ISO is backwards. As you lower your ISO you loose light sensitivity giving you a darker image.
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