Auto focus help

[PhillKP]

Hi everyone,

I have a Tamron 18-270 lense for my Canon 500d, which I've had for a couple of years now. I love this lense because it's so versatile and takes great, sharp images, but just on the weekend, it has started playing up.

The Auto focus has stopped working. It just seems to search around, back and forward and not be able to focus at all.

I'm really hoping someone can help me out with solution, as I really cant afford to buy a new lense.

My other lenses work fine, so it's not the camera (thankfully!)

Thankyou
Phill

[Steven G Webb]

I have a couple of Nikon lenses that developed this same issue, they hunt for focus and will not stop. I believe there is a failure within my lens. To make matters worse neither of them are professional grade lenses and the cost to repair them exceeds their value; they have been used extensively. New replacements would cost more but repairing the old units won't make them new again. Best wishes on a positive resolve for your issue.

[Dirk]

did you try to clean the contacts on the tamron lense

[PhillKP]

Yeah I did mate, thanks for the suggestion though.

[poloman]

Cycle the af switch.

[Dirk]

good one , switch could be naughty .. also check if the lens has got a af switch that it is on A not M .. then camera body will thinkt it is on A but if you set it m , you won't get good autofocus
and check if setting the VC to off helps too

maybe there is warranty on the lense , so check it asap.

i myself have never been a great fan of big range zoomlenses for dslr , just because the about only thing they are good at is range , mostley not iq .

[kennethwfd]

what lighting conditions are involved? Many lenses/cameras have issues with AF in poor light They include my Fuji HS20 and sigma 150 - 500 lens. Have you tried in bright sunshine & still got a focusing issue?

[Dirk]

and check if it really is the lens buy using one from a canon friend or the shop where you bought it

it can happen that things go defect and it is always said . that is one of the reasons i have so many stuff i have backup.

[PhillKP]

Thanks guys,
Yes, I've tried the lense in different conditions, including full sun, and I've also tried other lenses. They all work fine, so I think this one is unfortuneately dead! :-(
Thanks for all the advice and suggestions.
Phill

[Dirk]

no problem with trying to help.. sad that you now have to look far a new lense . perhaps safe to buy extra warranty on it this time ..