The SP90mm 1: 1 macro lens retains the outstanding optical quality provided by the highly rated Tamron SP90mm it succeeds. With emphasis on portability, the lens is now considerably smaller and lighter, measuring 97mm in length and weighing only 403g. It boasts high resolving power and sharp image depiction with ideal background blur. The lens has a new focusing ring clutch, which engages and disengages the focusing gear. Now the switch between AF and MF is a simple slide of the focusing ring forward or back. This mechanism and a wide, smooth focusing ring make delicate manual focusing in the macro mode easy and precise. Connection and disconnection of the focusing gears is done by sliding the focus ring back and forth, leaving the ring properly positioned for focusing.