The size and weight imbalance of the Hassy lenses does seriously impede handheld use on the smaller cams. On bigger DSLRs like the Nikon D700, D800, D810, D850 they're a bit more manageable, at least the 60-80-100 CF/Cfi/CB. The 40 and 50 are just huge/heavy, the 120/150 tricky, the 250 hopeless without a tripod. More @Wikipedia
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