Positives:
-L'autofocus Is extremely quiet even virtually inaudible! I remain amazed! the focus of my canon 18-55 drill make a sound in comparison! Moreover it is precise and efficient, no development problem (bright enough in the middle)
-The Stabilizer is also highly effective and its effectiveness is visible to the eye! At 270mm, stabilizes and I see my image and tremors freeze ... impressive!
-Compact, Leger, Manufacturing Quality, Sun visor.
Negative points:
-rare Are suitable dry clichés: RAW + compulsory reprocessing. Those who do not want to bother with that, I recommend instead a kind SX40 HS Bridge to see the same price cheaper.
-This Lens for Canon mount, why have reversed the direction of the zoom ring ??
-Not Usable at night because very little light, provide another lens, bright.
I strongly advice that choice any good photographer who wishes to prolong the life expectancy of his back by not lugging 15 different objectives in its excursions and all good amateur photographer like me who can not afford to buy 10 goals salary costs 1year order to make quality pictures. Quality objective. Good job Tamron
Warning: After 1 month of use (including 2 intensive use), AF is not as effective at the beginning. He became slow and risky ... The ultrasonic technology seems quite innovative but I highly doubt its reliability over the long term (or even medium term), a standard mechanical AF remains a great value and a reference in terms of reliability . Opt instead for the cannon 18-200 if you have the opportunity.