The Canon EF-S 10-18mm f/4.5-5.6 IS STM is a low cost wide angle lens for APS-C crop sensor cameras. It is light weight and optically gives really good results. The lens has Image Stabilisation (IS), and a Stepper Motor (STM) for fast autofocus.
Like its 18-55mm cousin, there are two toggle switches on the barrel of the lens. One turns image stabilisation on and off, whilst the other selects manual or auto focus. The electronic manual focus ring is at the front, whilst the zoom ring is the more substantial ring in the middle of the lens.
Image Quality of the EF-S 10-18mm
The EF-S 10-18mm delivers good image sharpness across the frame with even with a wide open aperture. Wide open aperture corner performance trails centre of the frame performance slightly, but the image quality remains quite similar over the entire focal length range. Selecting a narrower aperture, often results in improved image sharpness – especially in a budget lens. However, the EF-S 10-18mm shows diffraction that becomes noticeable at f/6.9.
Vignetting can be an issue, most notable at wider apertures. At 10mm f/4.5, this lens shows significant vignetting, improving at 12mm f/5.0, and at f/8 vignetting is reduces to about 1.5 stops at 10mm and approximately one stop over the balance of the focal length range. There is moderate chromatic aberration is present over the entire focal range.
This lens shows moderate barrel distortion at 10mm. The distortion diminishes until becoming negligible at 14mm. The distortion transition continues with mild pincushion distortion showing at 18mm.
The Canon EF-S 10-18mm f/4-5.6 IS STM is a budget lens, but is great for ultra-wide shots for an APS-C camera. A good purchase for a beginner or low-budget photography.