Canon EOS 550D review (Rebel T21)
Having the largest resolution in it's range puts a far amount of pressure on the EOS 550D to comfortably blow the opposition away.
The 18MP CMOS sensor makes a fairly sizeable impression as far as file size is concerned, which had an obvious impact on the buffer, but other than the increase in potential magnification not a huge amount more is gained.
The nine-point focus system offers selectable areas across the frame, and even when swapping between these zones the focus speed remained impressively rapid and, when left to the automatic offering, was superbly quick even in low light.
Only when the live view was in use did the EOS 550D's AF slow, as the selectable focus area took a long time to manoeuvre into the correct position using the d-pad.
The metering functionality, which almost doubles the metering points from 35 to 63, has a less obvious impact when shooting, but provides an impressively balanced exposure overall. In brighter conditions the EOS 550D successfully kept the amount of blown highlights to a minimum, even in longer exposures on a cloudy day. In fact, the exposure control was excellent in numerous situations, and the low light performance was a particularly impressive example of that. T
here was very little to pick between the higher ISO settings in terms of noise, with only an extreme amount of magnification in a photo editing program capable of showing the differentiation outside of the EXIF data. Leaving the camera on the auto ISO setting did produce some mixed results and lengthy shutter speeds, which can heavily comprimise the focus when off tripod due to camera shake, but manually upping the settings to 3200, 6400 or even the H 12,800 mark resulted in far sharper shots.
Unlike recent Micro Four Thirds models the EOS 550D isn't overrun with preset picture modes offering such niche settings as Tilt And Shift or Pinhole, instead sticking to more traditional offerings such as Portrait and Monochrome. On the basic settings there was no evidence of over-saturation, which has occasionally blighted Canon DSLRs, and colour quality in general was impressively balanced, keeping reds in check without dulling the entire image.
The 3.7fps frames per second rate is quite impressive when in JPEG shooting, and in spite of the quoted numbers went well beyond 34 images before slowing down, slowing in pace at around the 60 images mark. Involving Raw led to a more noticeable drop in pace as the buffer quickly fills after a couple of seconds.
One of the major improvements in terms of image quality over the EOS 500D isn't related to the stills, with the video having 24fps and 30fps frame rates available. The result is far smoother motion overall, especially when panning and recording rapid motion. Although the whirr of the AF is still noisy in terms of being picked up by the internal microphone, a directional mic at least maximises the potential for cutting out unwanted environmental noise, even if it requires the extra expense. Although not quite up to the standard of its more professionally-aimed sibling, the 5D Mk II, the video outputted by the EOS 550D was extremely impressive for the price range. See examples of video taken on the 550D, from ownes of the camera.