Technology Tales

Adventures & experiences in contemporary technology

No autofocus?

25th March 2009

Sigma 18-125mm f/3.8-5.6 DC HSM zoom lens

Recently, I recently treated myself to a Sigma 18-125 mm f/3.8-5.6 DC HSM zoom lens for my Pentax K10D. There was a wait for the item to appear and I then found that the lens’ autofocus facility wasn’t compatible with the body. Standard wisdom would have it that I sent the thing back and ask for a replacement or a refund.

Perhaps inexplicably, I did neither. In fact, I came to the conclusion, that since I make photos of landscapes anyway, that been slowed down by the lack of autofocus was no bad thing except perhaps when appealing light makes fleeting appearances. It is true to say that a used Pentax manual focus lens would have been cheaper but I did what I did.

The camera’s autofocus indicator still works and the 18-55 mm zoom that came with the camera wasn’t impressive anyway, so taking matters into my own hands was something that happened a lot. Now, I have better quality glass in front of the sensor and with a metal mount and longer range too. The lens comes with a petal hood too, though I keep that for when I really need it rather than keeping it on the lens and stopping myself focussing the thing.

Speaking of zooming and focussing, the controls work well and smoothly without being at all loose. The AF setting gets used to lock the focus and the zoom can be locked at the wide end so that the lens doesn’t get into the habit of zooming under the influence of gravity, not a bad thing. For future lens purchases, I might be more inclined to ask about compatibility next time around (I may have been spoiled by the Canons that I used to use) but I remain content for now.

All in all, it feels like a quality item and it’s a pity that Pentax saw fit to make the changes that they made, or that Sigma didn’t seem to have kept up with them. Saying that, my photographic subjects usually don’t run off so being slowed down is no bad thing at all, especially if it makes me create better photos.

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