Testing sigma 28-105mm f2.8-4

Have to say from the looks of it the lens is quite sharp but wish it was a continues f4 but have to say when you expose it correct the exposure changes not too extreme. Also tried out the under cranking setting at the end and slowed the footage down to get some light streaks when cars passed by but have to say the exposure is not slow enough, but have to say anything slower be better of doing time lapse for the long exposure plus able to get 5k footage instead of 1080p but have to say its ofcourse less of an hassle this way importing the footage.