Excerpt: An 88-400mm equivalent, this is Canon's longest EF-S (digital only) zoom, and roughly the low-cost digital alternative to its 100-400mm f/4.5-5.6L full-frame "white" image-stabilized zoom that's so hot with pros.
REVIEW: Canon EF-S 55-250mm f/4-5.6 IS STM Lens Review
26 February 2010
Excerpt: This telephoto zoom lens provides an angle of view equivalent to an 88-400mm used on a 35mm camera. This version is an update to the previous Canon 55-250mm IS II lens, adding Canon's new stepping motor technology, which promises smoother, quieter autofocus performance, which is especially suited to...
Excerpt: The EF-S 55-250IS is a relatively new lens designed to supplement the EF-S 18-55IS "Kit Lens" for the Digital Rebel line of DSLRs. Like the EF-S 18-55/3.5-5.6 IS, the 55-250/4-5.6 IS uses Canon's new low cost IS system.
Excerpt: Features and handling The unusual 55-250mm focal length range of this telephoto lens butts up neatly with Canon’s 18-55mm standard kit lens. Between them, the two optics offer EOS users an uninterrupted range of 18-250mm – that’s 29-400mm once you factor in the EOS system 1.6x crop factor.
Conclusion: When writing the summary of this particular lens we can easily say that we get what we paid for. After spending less than 300 USD we can get a lens with a good resolution at the whole focal length range, with well controlled chromatic aberration and optical stabilization – maybe not being 4EV, but...
Cons: slight focal plane tilt which results in small, however measurable, differences in chromatic aberration and resolution levels between the two sides of the frame, noticeable astigmatism, relatively large vignetting for all focal lengths, too much plastic in its body
Conclusion: The Canon EF-S 55-250mm f/4-5.6 IS is a tiny tele lens with a comparatively impressive performance potential. The resolution is very good across the range. Chromatic aberrations are almost a non-issue in field conditions. The level of distortions remains moderate.