Timing & Performance

Anybody buying a G11 to accompany their DSLR will be in for a bit of a surprize as they find themselevs having to wait for the camera to respond. Its shutter lag is very good but quite a lot of the other things it does require a little bit of patience. This isn't helped by the (at least) 1.5 second delay in showing the review image after you've taken a shot - a black screen is enough of a feature of the G11 user experience to make it feel slower than it really is. Overall it's a reasonable but not exactly impressive performance.

Timing Notes

All times calculated as an average of three operations. Unless otherwise stated all timings were made on a 3648 x 2736 Fine JPEG image (approx. 1,700 KB per image). The media used for these tests was a 8.0GB Lexar Professional 133x SDHC card.

Action Details
Time, secs

Power: Off to Record

Power: Off to Play Image displayed 1.2
Power: Record to Off Lens retracted and all activity ceased 1.5
Power: Play to Off When buffer is empty (lens extended) 1.0
Power: Play to Off When buffer is empty (lens already retracted) < 0.2
Record Review Image displayed 1.5
Mode: Record to Play   2.0
Mode: Play to Record   2.1
Play: Magnify To full magnification (10x) 1.0
Play: Image to Image Time to display each saved image (fade effect transition) ~ 0.7
Play: Image to Image Time to display each saved image (no effect) *1 ~ 0.5
Play: Thumbnail view 3 x 3 thumbnails < 0.3

Action Details
Time, seconds
Zoom from Wide to Tele 28 to 140 mm (5 x) 1.7
Half-press Lag (0->S1) Wide angle (AiAF or FlexiZone focus) 0.5 - 0.7 *2
Half-press Lag (0->S1) Telephoto (AiAF or FlexiZone focus) 1.0 - 1.3 *2
Half to Full-press Lag (S1->S2) LCD live view ~ 0.17 *3
Half to Full-press Lag (S1->S2) Optical Viewfinder < 0.1
Full-press Lag (0->S2) LCD live view, wide angle ~ 0.4
Off to Shot Taken LCD live view 2.2
Shot to Shot Flash off, JPEG Fine 2.4
Shot to Shot Flash off, RAW + JPEG 2.9
Shot to Shot Flash on (red-eye reduction off) *4 2.7
Shot to Shot Flash on (red-eye reduction on) *4 2.8
*1 You can also hold down the left or right buttons and scroll very quickly through images at approx 5 frames per second.
*2 Under ideal conditions. The G11 focus slows down in low light at longer focal lengths and when shooting at or near the closest focus distance.
*3 With the flash on the shutter lag extends to around 0.3 seconds
*4 In this test the subject distance is only 3 feet (0.9 m) - the recycle time will increase at greater subject distances and after a few consecutive shots.

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).

(Prime AF/AE)
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)

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. The medium used for these tests was a 8.0GB Lexar Professional 133x SDHC card. Shutter speed was kept above 1/200 sec and aperture at F3.5 during these tests.

Continuous drive mode

The Continuous AF mode shows the normal live preview between frames (and attempts to refocus between shots), but the normal Continuous mode only shows a very brief review image after each shot, and the focus is fixed after the first shot. It's worth noting that the figures below (and those quoted by Canon) are only for ISO settings of under 400; at higher ISO's the frame rate drops to around half these values.

Image Type
Avg. frames
per sec
Frames in a burst *1
10MP RAW + JPEG *3 Continuous 0.8 fps No Limit n/a
10MP RAW + JPEG *3 Continuous AF 0.7 fps*3 No Limit n/a
10MP Fine Continuous 1.1 fps No limit n/a
10MP Fine Continuous AF 0.8 fps *3 No limit n/a
10MP Fine Continuous mode (flash on) 0.9 fps *4 No limit n/a

*1 In a single "burst" (finger held down on shutter release).
*2 With the shutter release held down. With a fast card it is impossible to fill the buffer
*3 Average speed - it will slow down if the camera has trouble focusing
*4 With the flash turned on, the time in between the first and second shot in continuous mode is quite long (around 2 seconds) but then the camera continues to shoot at the same speed as if the flash was not turned on, but the flash continues to fire, though with less power and duration.

Around 0.8 fps isn't the most impressive continuous shooting rate (though fast continuous shooting has been the unnoticed casualty of the megapixel race) but we're impressed that it manages this while shooting RAW+JPEG. We also like the ability to get a faster pace out of the camera if you don't want the cameras to refocus between shots.

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 an 8.0GB Lexar Professional 133x SDHC card.

The G11 is faster to write the files but, oddly, slower to display its image results

Image Type
Time to store

Time to display

File size *1
Images on a *2
2.0GB Card
10MP RAW 2.0 ~1.5 9,500 KB 136
10MP RAW + JPEG 2.0 ~1.5 11,200 KB *4 114
10MP JPEG Fine ~1.2 ~1.0 1,700 KB 749

*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 With transition effects turned off
*4 Combined size of RAW and JPEG files