There is disclosed an adapter ring for rotation of a photographing lens barrel, the adapter ring being fitted into an outer periphery of the photographing lens barrel, the adapter ring being rotated through engaging with a ratchet wheel having a plurality of pawls which ratchet wheel rotates in conjunction with a dial disposed in a waterproof protector. If the current retry count is at least a predetermined number of times the control portion turns on a cooling fan device. A digital image containing a primary object dimension and a reference object dimension in substantially the same plane undergoes digital image processing to provide improved measurement capability. Sets of transactions are formed from the several transactions.