Meter Sub-Ranging and Its Effects

The Pocket Spot Light Meter sub-ranges between 5 and 6 EV. This means that at less than about 6 EV, the meter changes from 1 degree to 3 degree reading. (To judge 3 degrees is the same as 1 degree, but use the thickness of the case. Remember that the actual spot is mostly square, not round as the site implies.)

To optimize meter sensitivity over the widest range, the Pocket Spot Light Meter subranges in two places: at the low end and the high end. For various reasons, the high end sub-ranging is not an issue and will probably never be noticed. But because we photographers are so interested in the shadows, there are times when the EV 5 to 6 range is very important. It is in this range that the meter sub-ranges, i.e. it changes from 1 degree to 3 degrees to gather more light.

So, what happens if the one degree shadow is surrounded by something slightly brighter and the meter sub-ranges? If it isn't that much brighter, the meter will meter the 3 degrees and that is that, but if it is several stops brighter, it will go between 1 degree and 3 degrees displaying a reading that oscillates between the brightness of the 1 degree and the 3 degree. This can be confusing, but knowing what the meter is doing can clarify the reading.