Sony’s 18-250mm superzoom features a variable aperture of f/3.5 at the wide end, closing to f/6.3 at the long end.Mounted on a Sony D-SLR with an APS-C sized sensor like the A230 or A550, the Sony 18-250mm F/3.5-6.3 DT AF offers a 14x magnification that’s equivalent to 27-375mm when the 1.5x crop factor is considered, but isn’t suitable for full-frame D-SLRs.
The design of the lens features a large zoom ring that’s finely rubberised and was smooth throughout the entire focal length on our sample. The focus ring is a third of the size of the zoom ring and although it’s well balanced, it wasn’t entirely silent to use in MF mode. The only switch on the lens is the zoom lock and, given the choice, we’d prefer a MF/AF switch on the lens itself rather than having to select the focus mode from the camera’s body.
Optical image stabilisation isn’t featured on this lens – it’s not necessary on Sony optics because Alpha D-SLRs feature the SteadyShot image stabilisation system built into the camera body. The motor that drives the lens’s autofocus isn’t a silent unit, so you can expect quite a whirr in operation. Also, the AF tended to hunt back and forth a little before locking on to the subject in gloomy lighting conditions.
This is quite a light lens, weighing just 440g and can focus to a minimum distance of 45cm. There are three aspherical lens elements along with low dispersion elements to minimise flare and aberrations. At the front it uses a 62mm thread.
AT A GLANCEPrice: £439
Mount: Sony/Minolta
Construction: 16 elements in 14 groups
Aperture blades: 7
Max aperture: Wide f/3.5, tele f/5.6
Min aperture: f/22-40
Minimum focus: 45cm
Filter size: 62mm
Dimensions (DxL): 75x86mm
Weight: 440g
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