I think, Paul, that you are confusing the ZFR3/4 telescopic gunsights, and the plain vanilla telescopes mounted in Galland's machines, and in the photos posted by Chris.
The ZFR dual gunsight shown below, from
www.archiv.de, is one tested in the 109G. And yes, it was mainly used in the Me 410s that mounted the twin 30mm cannon and the 50mm BK5 cannon -- but in its 4x magnification form.