Great question Ruth! EV is your “exposure value” which can be assessed by looking at the histogram while reviewing a photo. You can also check your EV on DSLR cameras before you take a shot. There should be a sliding scale in the viewfinder that looks like this:
–<----|---->+
and tick marks will move back and forth along the scale to tell you if your camera thinks the shot is over/underexposed. Of course your camera can’t read your mind. So basically, I have found checking the EV before hand will increase your chances of a good histogram, but it is always a good idea to review the histogram and make changes to exposure as you see fit :-) Hope that answers your question, if not please let me know. We’ll definitely be diving into this full on in a future post!

You’re very welcome Tammy :-)