Canon G1X Mark III Performance

Generally good performance for its class.

Startup to first shot time was about average for its class, but much slower than most interchangeable lens cameras since it needs to extend its built-in zoom lens when turning on. Switching from Play to Record and taking a shot was faster at about 1.4 seconds.

The G1X Mark III's single-shot full autofocus shutter lag when shooting the same target multiple times was much faster than average for a fixed-lens enthusiast camera, and much improved over the G1X Mark II. The Mark III's full AF shutter lag clocked in at an average of only 0.115 second at wide angle using center (1-point) single-shot AF, compared to about 0.2 second for its predecessor. Full AF shutter lag was just a bit slower at full telephoto, at an average of 0.124 second versus 0.37 for the Mark II. We did however notice a lot of variation between trials, much more than we're used to seeing. It was as if the camera was performing a long polling loop to check if the shutter button is pressed. The theory is if the shutter button was pressed just before it was polled, the lag was extremely low, as low as 0.03 second in our measurements. However if the press just missed a poll, full AF shutter lag was much longer -- up to 0.22 second in our tests, though that's still fairly quick.

Enabling the built-in flash raised shutter lag to an average of about 0.4 second to account for the metering preflash, a significant improvement over the Mark II's 1.03 seconds.

Manual focus shutter lag was on average a little faster than with autofocus at 0.1 second, also improved over the G1X' IIs 0.24 second, though it too showed significant variation ranging from 0.078 to 0.182 second in our tests.

When prefocused, shutter lag dropped to an average of only 0.033 second (without much variation) which is quite fast and much improved over the G1X II's 0.091 second.

Shot-to-shot cycle times were noticeably improved over the G1X II in single-shot mode as well, at about 0.4 seconds for best quality (Large/Fine) JPEGs or RAW+LF JPEG files, versus just over a second for the Mark II. We no longer test just RAW file cycle time in single-shot mode, as it's usually somewhere in between JPEG and RAW+JPEG.

The PowerShot G1X Mark III's fastest continuous shooting mode (Continuous H with One-Shot AF) was much faster than the Mark II's, particularly when shooting RAW files. The G1X III managed just over 9.3 frames per second no matter the file type. That's a generous increase over the Mark II's 5.3 fps for just JPEGs, and a huge improvement when shooting RAW files as the Mark II dropped down to only 1.5 fps for RAW and 1.3 fps for RAW+JPEG files. Note that focus is locked at the first frame of a burst in this mode.

Canon rates the G1X III's top Continuous AF (Servo AF) burst mode speed at 7.0 frames per second, however we did not test that in the lab. The camera also provides One Shot L and Servo L modes, both rated at 4.0 fps.

Buffer depths were fair in Continuous H mode at 23 best quality JPEGs, 16 RAW and 16 RAW+JPEG files before the burst rate slowed in our tests, but you can expect deeper buffers when shooting at slower rates. Since the burst rate is much faster, buffer depths aren't really comparable to the Mark II. Clearing times were a bit sluggish with a fast SDXC UHS-II card, though. ranging from 4.7 seconds after a max-length burst of JPEGs to 14.7 seconds after a max-length RAW+JPEG burst. Note that the G1X III is not UHS-II compliant, but takes advantage of the card's UHS-I mode.

The built-in flash took an average of 3.8 seconds to recharge after a full-power discharge, a little slower than the Mark II's 3.2 seconds.

Bottom line: The Canon G1X III generally exhibits good performance, though there are a few sore points. Powerup to first shot is a bit slow compared to ILCs but typical for a fixed-lens camera with a zoom that needs to be deployed. Full autofocus shutter lag is very fast on average, but can vary a lot (see above). Prefocused shutter lag is quite low, cycle times are quite fast, and continuous mode performance is very good with a top burst speed of about 9.3 frames per second. Buffer depths are decent given the burst speed, but could be better (however keep in mind you can shoot at the slower rate with deeper buffers). Clearing times are a bit sluggish, though, and the camera doesn't let you change settings while it's flushing frames to the card.

Battery Life
Poor battery life.

The G1X III uses a custom NB-13L rechargeable lithium-ion battery for power and ships with a dedicated charger, although in-camera charging via USB is also supported. CIPA battery life has fallen compared to its predecessor by some 40 shots, and is well below most ILCs and even most compacts at only 200 CIPA-rated shots per charge. There is an ECO mode which improves battery life to 250 shots (down from 300 on the Mark II), which works by dimming and then shutting off the display more quickly than normal, but battery life is still not great. Given the poor battery life rating, we strongly recommend you pick up a spare battery for extended outings.

The table above shows the number of shots the camera is capable of (on a fully-charged rechargeable battery as appropriate), based on CIPA battery-life and/or manufacturer standard test conditions.

(Interested readers can find an English translation of the CIPA DC-002 standards document here. (180K PDF document))