wISOr Loc: Austin, TEXAS

It is my understanding from Sigma there are 150-500 lenses out there within the range of these SNs: 10674301-10972000, that have focusing problems. I contacted Sigma because I wanted to purchase a used 150-500 and was curious about the SN numbers. The lens I bought was not in that range and works like a charm on my D7000.

bee7474 Loc: Selah, Wa

I have never noticed any problem with focusing at 500 and I don't use a battery pack. I use it with a Canon 5D Mark II, don't know if that makes a difference. Bee

Hal81 Loc: Bucks County, Pa.

Barrow the friends battery grip and see if that solves the proublem.

speters Loc: Grangeville/Idaho

I always hated the AF on Sigmas, but what you discribe, would drive me bananas!

rogerl Loc: UK (Harrogate, North Yorkshire)

Many thanks to all who contributed advice and suggestions; I’m very grateful. I bought the lens for a trip to Zambia (we’ve just returned & obviously there was no problem with lack of light!). It seemed to work fine before we left (although I didn’t get much practice with it). This is where we are up to:
1. I have cleaned the lens & camera contacts with a lint-free cloth (is there anything else I should use?)
2. I phoned Sigma UK who said that they do not know of any problems with AF with the D200 (I prefer to believe MT Shooter on this one!). They recommended that I clean the AF sensor by air blowing the chip with the mirror raised; I have done this. They also said that, if problems persist, I could send the lens to them for checking – if they don’t find a fault they’ll return it to me without charge or if they do find a fault, they’ll give me an estimate.
3. There is no lens fine tune facility on the D200 (but thanks erjmaine)
4. The lens serial number is not in the range SNs: 10674301-10972000 (thanks wISOr)
5. The battery pack from the D700 doesn’t fit the D200 (& I don’t know anyone who has a D200 pack I could borrow).

On the very limited testing I’ve been able to give it since returning, the lens seems to be working OK now so maybe one of the above worked. It also seems to work fine on my wife’s D90 (maybe she’d better watch out!).

Trying to photograph Birds in Flight was a problem in Zambia – it worked on a few but not on the majority. I haven’t yet been able to test BIF in UK (the pigeons in the garden won’t co-operate & the weather’s not helping). If BIF is still a problem do you think a battery pack would help (I don’t want to buy one on spec as I don’t normally have a need for one but would do so like a shot if it would improve BIF - especially as I'm thinking of a trip to Wales to try my luck at the red kite feeding station)?

lame duck

I Have a nikon D 300 and the Sigma 150-500 lens no trouble at all.
Lame duck