Timing & Performance
Like most of Canon's A series PowerShots, the A520 has fairly pedestrian performance that reflects its pricing and positioning as a budget camera. Some aspects of operation feel very snappy indeed - the menus are very fast and shutter lag is pretty low, and overall performance is as good as you could expect at this end of the market. But there are times when the A520 feels very sluggish if you're used to a faster camera. We can live with the rather leisurely power up and power down times and slow playback (image to image browsing), but the slow focus (especially at the long end of the zoom) and long shot to shot time - especially with flash - is more serious, and something you need to be aware of if you like to fire off a lot of shots in rapid succession. It's a real pity Canon couldn't justify the new DIGIC II processor in the A520, as I'm sure this would've boosted performance significantly. Maybe next time.
All times calculated as an average of three operations. Unless otherwise stated all timings were made on a 2272 x 1704 SuperFine JPEG image (approx. 1,965 KB per image). The media used for these tests was a 512 MB SanDisk Ultra II SD card.
|Power: Off to Record||2.5|
|Power: Off to Play||Image displayed||2.9|
|Power: Record to Off||All activity ceased||1.8|
|Power: Play to Off||When buffer is empty, lens already retracted||~0.5|
|Power: Play to Off||When buffer is empty, lens extended||1.7|
|Record Review||Image displayed||~1.4|
|Mode: Record to Play||1.2|
|Mode: Play to Record||Lens already extended||~1.9|
|Play: Magnify||To full magnification (10x)||~1.8 *1|
|Play: Image to Image||Time to display each saved image||0.8*2|
|Play: Thumbnail view||3 x 3 thumbnails||1.1|
|Zoom from Wide to Tele||35 to 140 mm (4 x)||1.7|
|Half-press Lag (0->S1)||Wide angle||~0.8|
|Half-press Lag (0->S1)||Telephoto||~1.0 - 1.6|
|Half to Full-press Lag (S1->S2)||LCD live view||~0.1|
|Half to Full-press Lag (S1->S2)||Viewfinder||<0.1|
|Full-press Lag (0->S2)||LCD live view, wide angle||~0.9|
|Off to Shot Taken||LCD live view||~3.1|
|Shot to Shot||Flash off||2.1|
|Shot to Shot||Flash on (with or without redeye)||~ 7.0|
|*1||The A520 uses cacheing in playback mode. This figure is for the first time you magnify an image - if you return to the same image without leaving playback mode the time to magnify drops to around 1.0 sec.|
|*2||This is for none-rotated (i.e landscape orientation) shots. If auto rotate is enabled each vertical shot takes approx. 2.0 secs to display.|
So a fairly mixed bag, then. To be fair, in use the A520 only ever feels slow when it's struggling to focus (especially at the long end of the zoom in low light) or when you're shooting with flash when the recycle time really slows things down.
Lag Timing Definitions
|Half-press Lag (0->S1)
Many digital camera users prime the AF and AE systems on their camera by half-pressing the shutter release. This is the amount of time between a half-press of the shutter release and the camera indicating an auto focus & auto exposure lock on the LCD monitor / viewfinder (ready to shoot).
|Half to Full-press Lag (S1->S2)
The amount of time it takes from a full depression of the shutter release button (assuming you have already primed the camera with a half-press) to the image being taken.
(Take shot, AF/AE primed)
|Full-press Lag (0->S2)
The amount of time it takes from a full depression of the shutter release button (without performing a half-press of the shutter release beforehand) to the image being taken. This is more representative of the use of the camera in a spur of the moment 'point and shoot' situation.
(Take shot, AF/AE not primed)
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. The media used for these tests was a 512 MB SanDisk Ultra II SD card. Shutter speed was kept above 1/200 sec during these tests.
Continuous drive mode
The A520 has only a single continuous shooting modes, which in our tests averaged around 1.7 fps (a little short of the 1.9 fps quoted by Canon). In continuous shooting mode the A520 does not show a live preview, but does display a brief review image for each picture taken.
Frames in a burst *1
|2272 x 1704 JPEG Super Fine||Continuous||1.66 fps||4||0.74 fps|
|2272 x 1704 JPEG Fine||Continuous||1.72 fps||7||0.83 fps|
|2272 x 1704 JPEG Normal||Continuous||1.76 fps||14||1.05 fps|
|1600 x 1200 JPEG Super Fine||Continuous||1.6 fps||8||1.06 fps|
|1024 x 768 JPEG Super Fine||Continuous||1.7 fps||20||1.25 fps|
|*1||In a single "burst" (finger held down on shutter release).|
|*2||The A520 does not stop shooting once the buffer is full, but the frame rate drops significantly. The rate varies, so the figure shown is an average measured over 20 frames.|
Not a bad performance at all for a camera in this class - and it's nice that the camera doesn't lock up once the buffer is full, but starts to write to the CompactFlash card, meaning you can go on shooting - albeit at a much slower pace.
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 512 MB SanDisk Ultra II SD card.
Time to store
Time to display
File size *1
Images on a *2
512 MB Card
|2272 x 1704 JPEG Super Fine||~2.9||~0.8||1,965 KB||243|
|2272 x 1704 JPEG Fine||~2.4||~0.7||1,155 KB||435|
|2272 x 1704 JPEG Normal||~2.0||~0.6||502 KB||859|
|1600 x 1200 JPEG Super Fine||~2.6||~0.7||965 KB||483|
|1024 x 768 JPEG Super Fine||~2.1||~0.6||399 KB||835|
|*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).|
With write times averaging around 2.9 seconds for a 4MP (1,965 KB) Super Fine JPEG the A520 is fairly speedy for a camera of this classs, but the transfer rate - approximately 680KB/s - means fast cards will offer little advantage in this camera.