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

Action Details
Time, seconds
Zoom from Wide to Tele 28 to 504 mm (18 x) 3.2
Half-press Lag (0->S1) Wide angle, iESP ~0.7 *2
Half-press Lag (0->S1) Telephoto, iESP ~0.8-1.5*2
Half to Full-press Lag (S1->S2) LCD live view ~0.08 
Half to Full-press Lag (S1->S2) Viewfinder ~0.1
Full-press Lag (0->S2) LCD live view, wide angle ~1.0
Off to Shot Taken LCD live view ~4.5
Shot to Shot Flash off 3.8 
Shot to Shot Raw mode (no copy JPEG) 7.7 
Shot to Shot Flash on (red eye off) 4.4 
Shot to Shot Flash on (red eye on) 5.6 
*1 To magnify a RAW image takes around 7.5 seconds (6.5 seconds to load)
*2 Focus speed varies quite widely. In low light even at the wide end of the zoom it can be as much as 1.0secs. Tele focus speed in low light can stretch to several seconds, and even in good light it can take over a second.

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).

Image Type
Avg. frames
per sec
Frames in a burst *1
3072 x 2304 JPEG SHQ Continuous 1.0 fps 3-7 *3 ~ 5.0s *4
3072 x 2304 JPEG HQ Continuous 1.1 fps 13-15 *3 ~ 4.0s *4
2048 x 1536 JPEG SQ1 Continuous 1.2 fps 24 ~ 3.9s *4
640 x 480 JPEG SQ2 Continuous 1.2 fps limited by card capacity n/a
2048 x 1536 JPEG SQ1 Continuous Hi 1 6.9 fps *5 15 ~ 14s *4
1280 x 960 JPEG Continuous Hi 2 14.2 fps *5 20 ~ 9.0s *4

*1 In a single "burst" (finger held down on shutter release).
*2 This is the time you have to wait for the buffer to clear before another full burst can be taken.
*3 We repeated this test over and over again and the amount of shots in a burst varied with no apparent cause. It appears to be simply related to the size of the file, and for sharp, detailed shots (the largest) it is nearly always 3 frames. Where the figure is greater than 3 or 4 frames the frame rate drops significantly for the remaining shots in the burst.
*4 You cannot take pictures whilst the buffer is being cleared.

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.

Image Type
Time to store

Time to display

File size *1
Images on a *2
1.0GB Card
7MP RAW ~6.3 ~0.3 *3 10,529 KB *4 97
7MP RAW + SHQ JPEG ~9.9 ~0.3 *3 10,529 KB *4 69
3072 x 2304 JPEG SHQ ~3.2 ~0.3 3,500 KB 246
3072 x 2304 JPEG HQ ~2.6 ~0.2 1,300 KB 561
2048 x 1536 JPEG SQ1 ~2.2 ~0.5 550 KB 1,305
1600 x 1200 JPEG SQ2 ~2.2 ~0.5 370 KB 2,063
640 x 480 JPEG SQ2 ~1.9 ~0.3 65 KB >10,000

*1 All file sizes are an average of three files. As is the case with JPEG it's difficult to predict the size of an image because it will vary a fair amount depending on the content of the image (detail and noise).
*2 Camera estimation.
*3 Time shown to display a screen res thumbnail
*4 All RAW files are 10,529 KB. If you choose to save a duplicate JPEG at the same time obviously this will take up additional space on the card

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.