Great value

I got this lens to replace the Tamron 70-300mm. I would skip the Tamron and just get this one. Just the quick switch focus is worth the money. If your in low light and the auto focus is hunting you can just grab the manual focus and go. The camera is choosing the wrong point for the focus, just grab the manual. No switching to auto focus required. It's also weather sealed and the image quality is great. It also has the focal length range to make this a decent walking around lens. I took some great fireworks images this independence day with this lens. I set the aperture to f11 and then took three to ten second exposures, with tripod of course. Worked great.

Nice general-purpose telephoto

I got this in the hopes of replacing both a Pentax 50-200 and a Sigma 70-300.

Luckily, the image quality seems to be a slight improvement over both, though they were acceptable on their own. This lens is just a bit smaller than the Sigma, though not close to the small size of the 50-200.

The Pentax 55-300 does not have a quasi "macro" mode as do some other 70-300's including the Sigma, and the closest focussing distance is 4.67ft (1.4m) which is not particularly close, either.

As seems standard with Pentax, the lens hood has a hatch to allow turning a polarizer filter, and the "Quick Focus" ring allows manual focus to fine-tune the auto-focus when the shutter is still half-pressed.

Not particularly a fast focusser, it can hunt in low-contrast situations and when going from very close to very far. Neither seems to be a real problem in normal use. The variable f4-5.8 speed is not great for low light but is is OK in most daylight circumstances and helps to keep the cost and size down.

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