Timing & Performance

Although overall the SP-550's performance isn't that different to the other cameras in its class it doesn't feel as fast in use, mainly down to a couple of key areas where it struggles to keep up. First, and most frustrating in everyday use, is focus. We found that even in good light the focus times meant too many missed shots, and in low light the camera can take well over 1.5 seconds to focus at longer focal lengths.

The other problem - seemingly common to all xD based cameras - is the speed of writing to the card and buffering problems, which produce a painful shot to shot time of just under 4 seconds (and occasionally mean you can't take a picture because the buffer is full). If you like to rattle off shots quickly using the SP-550UZ feels like wading through treacle. If you are a more considered shooter you probably won't notice. The burst mode (something Olympus makes a lot of in its marketing materials) is actually pretty limited unless you accept the serious compromises (low resolution, ISO restrictions, long recovery time) involved in the two 'High Speed' modes.

Timing notes

All times calculated as an average of three operations. Unless otherwise stated all timings were made on a 7MP SHQ JPEG image (approx. 3,500 KB per image). The media used for these tests was a 1.0GB Olympus xD-Picture Card Type H.

Action	Details	Time, secs
Power: Off to Record		2.7
Power: Off to Play	Image displayed	1.7
Power: Record to Off	All activity ceased	2.5
Power: Play to Off	When buffer is empty, lens extended	2.2
Power: Play to Off	When buffer is empty, lens already retracted	0.2
Record Review	Image displayed	~0.8
Mode: Record to Play		0.9
Mode: Play to Record	Lens already extended	0.8
Play: Magnify	To full magnification (8x)	~1.5 *1
Play: Image to Image	Time to display each saved image	~0.3
Play: Thumbnail view	2 x 2 thumbnails	0.6
Play: Thumbnail view	3 x 3 thumbnails	1.1
Play: Thumbnail view	4 x 4 thumbnails	1.6
Play: Thumbnail view	5 x 5 thumbnails	2.4

Continuous mode

The tables below show the results of our continuous shooting test, indicating the actual frame rate along with maximum number of frames and how long you would have to wait after taking the maximum number of frames before you could take another shot. Media used for these tests was a 1.0GB Olympus xD-Picture Card Type H. Shutter speed was kept above 1/200 sec during these tests.

Continuous drive mode

The SP-550UZ has a single continuous mode for shooting at full resolution, which averages at around one frame per second and has limitations on the number of frames in a burst. There are two high speed modes (Hi 1 and Hi 2), offering much higher frame rages (up to just under 15 fps by our measurements), but you are restricted to 3MP (Hi 1) or 1.2 MP (Hi 2) and - strangely - you can't use an ISO lower than 400 in these modes. Hi 1 and Hi 2 offer a 'pre capture' option that saves around 5 shots before the shutter is pressed, useful if you're trying to capture the decisive moment.

The SP-550UZ doesn't show a preview image when shooting in continuous mode, but does display a brief review image after each shot is captured. There is also an option to enable the autofocus during burst modes (with live preview), but this inevitably slows things down considerably (to as slow as 0.5 frames per second).

So then, if you want to shoot using all the SP-550's seven megapixels the continuous performance is pretty unimpressive; 3 frames at 1.0 fps (and a 5 second recovery) is way below the best competitor products. You can improve things a little by switching to the lower HQ mode, but the loss of quality is visible. That said, the ultra high speed capture of the Hi 1 and Hi 2 modes is certainly pretty unique, though with the size and ISO limitations it is far from perfect. If you'd like to see an example shot from the high speed modes click here (Hi 1) and here (Hi 2).

File Write / Display and Sizes

Timings shown below are the time taken for the camera to process and "flush" the image out to the storage card, the timer was started as soon as the shutter release was pressed and stopped when activity indicator went out. This means the timings also include the camera's processing time and as such are more representative of the actual time to "complete the task". The media used for these tests was a 1.0GB Olympus xD-Picture Card Type H.

File writing - even with the supposedly high speed 'H' cards - is a little pedestrian, and the long shot-to-shot times put a limit on the usefulness of RAW for a lot of real-world photography.