The highlight warning feature in our camera is supposed to tell us which pixels are overexposed. Sometimes called “blinkies”, the highlight warning flashes to show us areas of the photograph that are overexposed. 

In theory, this should be a more accurate way to evaluate our exposure than with the in- camera histogram, but it suffers from “safety margins” built in by the manufacturer. My testing has shown that these safety margins can range range from 1/3 stop to as large as 2 stops, and possibly more. This means that photographers relying on highlight warnings without testing may be underexposing by as much as 2 stops!

The problem is one of calibration. If the camera manufacturer is not giving us accurate information with the highlight warnings, how can we calibrate them to achieve a more accurate result? 

Calibrating is common practice across many disciplines when greater precision accuracy is required. We shouldn’t assume the camera manufacturer calibrated our highlight warnings to our specification. In fact, we should assume they are inaccurate. Only by testing can we prove our camera’s accuracy and calibrate its performance. No one will do this for us, we have to do it for ourselves.

If you want to learn how to calibrate your camera for more accurate exposures, you’ll need to purchase the course to continue.