Canon lens 15-85mm focus issue

[Mobaz]

A few weeks ago my 15-85mm began having a focusing issue. Whereas if the lens was sitting idle for a period of time; upon going to use it, it would take 8-10 seconds for the focus to begin working. After this initial period the focus would then "engage" and the lens would function as normal. This was the case in manual as well. In manual, you would have to turn the focus ring back and forth five or six times before it would finally "catch" and then begin focusing normally. Is this normal for this type of lens?

[pjmacd]

I have the 15-85mm lens and have never had the problem you are describing. My lens can go unused for weeks at a time, since I keep it on my infrared-converted T3i. It sounds to me like you may need to have the lens at least looked at by a camera technician, and possibly repaired.

[RobertTheFat]

It could be a battery issue if, for example, the autofocus motor has to wait for a weak battery to achieve the minimum necessary voltage. And the fact that it also happens in manual mode may not necessarily be inconsistent with that explanation. As one of the regulars (Ernie Biggs?) pointed out recently, some of Canon's recent lenses are fully electric, with even their manual focusing rings being nothing but a motion sensor.