Why not get a handheld meter?
Metered prisms are ok but they do require some interpretation and learning.
You don't say what the subjects are; are you photographing people, achetechture, landscape, studio work, product shots, weddings?
Modern handheld incident meters are in my opinion the fastest, easiest, and most reliable way to meter.
They don't get fooled easily and are quick to learn; turn it on, extend the dome, set the ISO, touch it to your subjects nose while pointed at the camera, dial the suggested setting into the camera, shoot.