I stuck the Better Beamer on the zoom last evening to give it a short workout. I was shooting ttl and the maximum shutter speed was 1/250th of a second. I am usually shooting these guys at 1/1600th to 1/4000th of a second.
Not bad, gave me good fill illumination and an interesting wing blur. I do need to figure out how to set the Godox tt685n speedlight up for high speed synch. Tonight I look for owls.