Question for a Nikon owner of a Sigma 150-500 HSM OS

[benhasajeep]

Sigma finally got back to me on my slow focusing speed after repair on my 150-500 HSM OS. The only local store near me does not stock Sigma so I can't compare with an instock lens.

Basically Sigma is telling me the lens was focusing faster than normal because of the fault that finally broke on the second use?? They are claiming that the lens is focusing at its correct speed now. This speed is noticeable slower than a body driven D type Nikon lens.

Just wondering if anyone has the 150-500 HSM. If they could do a quick focusing speed test. In good light focus on a near object say 10'. Then focus on a far object that would be near infinity. And roughly estimate the time it takes the lens to turn to get to the far focus from the near.

I am having a hard time believing this lens is operating correctly at this speed.

 

[Formatted]

KMH had / has one so he'll be able to tell you.

This speed is noticeable slower than a body driven D type Nikon lens.

The major downside of Sigma lenses is the slower AF.

 

[baturn]

Just tried this several times at different objects and distances, with 150 - 500 on D80. Refocus time was almost instantaneous. Would grip and fresh batteries make any difference?

 

[Formatted]

Just tried this several times at different objects and distances, with 150 - 500 on D80

I find the best way to test something like this is to go from close focus to infinity and time how long it takes.

 

[baturn]

I did as benhasajeep asked, but i also tried other objects, distances and reversing it ( from infinity to close) and focus time was always near instantaneous.

 

[benhasajeep]

Just tried this several times at different objects and distances, with 150 - 500 on D80. Refocus time was almost instantaneous. Would grip and fresh batteries make any difference?

Using 2 Nikon D300 bodies, one with grip, both have fully charged batteries. Thanks for checking.

 

[benhasajeep]

Yea, I figured as much. I think Sigma is blowing smoke that it was focusing faster because of a failure.

I guess about the only thing I can do. Is drive to a camera store with one in stock and compare side by side.

Basically I am going to have to pay to ship it back to them. Even though it wasn't right from the first time. Need to find another copy though. So, I can definately say lens A is 2x slower than lens B.
Thanks again.

I talked to Sigma again. And the reason they say the lens could focus faster before the barrel change was the lens was probably missing pulses as the lens turned to focus. And becuase it was not reading all the pulses it was moving faster to reach focus. The lens barrel I guess contains the electronics and thats why they changed the barrel as a whole. He said they do test all lenses for operations including focusing speed before it leaves the shop.

And that as an option, I can choose to speed up the HSM frequency to focus faster. But will lose low light capability.

I am going to have to drive a couple hours south to find a store with one in stock. Unless maybe I can find a place with one for rent. I don't want to lose any low light capability, but I also don't think this thing is anywhere near what it should be at.