Jargon buster
Electromagnetic diaphragm
Lenses with this type of aperture control are incompatible with older DSLRs including the D40, D40X, D60, D70, D70S, D80, D90, D100, D200, D300, D300S, D3000 and D5000, as well as the D1 and D2 series.
VC – Vibration Compensation
Tamron’s proprietary ‘Vibration Compensation’ system works in a different way to Nikon’s VR (Vibration Reduction) but with the same aim of reducing camera-shake.
Compatibility
The Sigma and Tamron 85mm lenses on test have electromagnetically controlled apertures, making them incompatible with older Nikon DSLRs.
Diaphragm blades
A larger number of diaphragm blades typically enables a better-rounded aperture when stopping down a little from the lens’s widest available aperture.
Autofocus system
All of the lenses in this test group feature ring-type ultrasonic autofocus, which is whisper-quiet, enables manual…