Sigma 170-500mm F5-6.3 APO Aspherical A-mount lens review by al_1571
|al_1571#7126 date: Mar-20-2010|
flare control: 5
|ownership:||I own this lens|
|compared to:||Tokina 100-300 F4 Big Beercan|
|positive:||Inexpensive. Focal Range. Compact for a 500mm tele.|
|negative:||Zoom Creep. No Focus Limiter. Awkward MF due to focus ring at rear of lens. My copy doesn't really get sharp until F10 but, is usbale at F7.1|
|comment:||I bought this lens, off Ebay, for some extra focal length now that I have the "birding bug". Just have had it one week and am pleased with it so far. Adjusting to the narrower field of view and slower AF, compared to my Tokina, will take some time. FYI... I handhold 90% of the time but, I am a stronger man also.|
My biggest gripe is having to shoot at F10-F14 for really sharp images. For the money I paid I should complain too much about the F Stop issue but, I will. And so, under the best conditions I shoot at ISO 320-500 to balance shutter speeds of 1/1000th to freeze BIF's.
The F Stop is relative to the focal length you are shooting at too. The closer I am to my subject the lower I can leave my F Stop at. I'll be sure to post an update down the road some. If you are looking for an inexpensive, longer focal length birding lens, this might be a good place to start.