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Canon G1 X Mark III brings zoom to its APS-C compact camera

Leica did it first, but it's telling that no one else has tried in the four-year interim.

Lori Grunin Senior Editor / Advice
I've been reviewing hardware and software, devising testing methodology and handed out buying advice for what seems like forever; I'm currently absorbed by computers and gaming hardware, but previously spent many years concentrating on cameras. I've also volunteered with a cat rescue for over 15 years doing adoptions, designing marketing materials, managing volunteers and, of course, photographing cats.
Expertise Photography, PCs and laptops, gaming and gaming accessories
Lori Grunin
5 min read

Not the prettiest camera we've seen.


While the Leica X Vario had the distinction of being the first APS-C (22.3 x 14.9 mm) compact with a zoom lens when it came out in 2013 -- they usually have fixed focal lengths -- no one has followed in Leica's wake with a more affordable model until now. There are good reasons for that, as we saw with the X Vario and with the specs for the PowerShot G1 X Mark III attest.

It incorporates the same larger-than-most APS-C sensor as the mirrorless EOS M5, a 24-megapixel Dual Pixel CMOS, which means the camera also gets fast phase-detection autofocus instead of slow contrast-detection.

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It's expensive...

When it ships in November, the G1 X M3 will cost $1,300 (£1,150; Canon Australia doesn't provide an RRP, but directly converted it's about AU$1,770). That's a lot more expensive than a typical flagship compact. But keep in mind that putting a fixed zoom lens on a bigger sensor without creating a concomitantly big camera is more expensive proposition.

As a refresher, the larger the sensor, the further from it a given focal-length lens has to be in order to cover the sensor entirely, and longer focal lengths need to farther away than shorter ones for the same reason. For a variety of other technical reasons, the widest aperture size also decreases as the focal length gets longer, and smaller apertures are undesirable because they let in less light and decrease the amount of background defocus you can get when the subject and background are close to each other.

That's why most APS-C compacts like the similarly priced Fujifilm X100F have a wide-angle, wide-aperture fixed lens, and why advanced compacts with zoom lenses generally have smaller sensors.

...with a slow lens, icky design and missing features...

The typical camera manufacturer's assumption is that if you're interested enough to pay more for a bigger sensor, you're discerning enough to want a fast lens. (Relatively narrow-aperture lenses are referred to as "slow.")

The G3 X M3's closest competitor in spirit is the old-but-still-kicking Panasonic LX100, with its slightly smaller 17.3 x 13mm Four Thirds sensor, but which has a significantly faster 24-75mm f1.7-2.8 zoom lens and which currrently costs about half the Canon's price.

Canon's 24-72mm lens' f2.8-5.6 aperture range means that at 72mm the LX100's is a full two stops wider -- that's a 4x difference in the amount of light that reaches the sensor. When you take into account the possibly larger pixels on the bigger Canon sensor, that works out to a smaller difference, but I highly doubt the sensor is two stops more sensitive; Canon's sensors just aren't that good.  On the other hand, the depth-of-field trade-off behind the subject between the two is about 6 inches/15cm in a typical shot from 10 ft/3 m away at 50mm, assuming the PowerShot hits f4 at 50mm. (In other words, a relatively trivial difference with respect to useful background defocus.)

And while f2.8 at 24mm sounds great -- and it is -- you don't typically shoot portraits or other types of shots where background defocus is important with a wide-angle lens because of distortion. You need the fast aperture at about 35mm-equivalent and longer, where the Canon has likely already hit f4 or more. Plus, its minimum focus distance is 4 inches/10 cm, farther than the typical 2 in/5 cm.

Enlarge Image

Relative sensor sizes.

However, as long as you don't care about modern features or 4K video, the photo quality should be significantly better than a camera with a 1-inch sensor and a fast lens, like the Sony RX100 V.

Canon has dropped the G1 X's original body design in favor of the G5 X Mark II's, with the functional but oddly wartlike front dial. On the inside, it's the EOS M5 mirrorless, and similarly lacks some of the same capabilities, such as 4K video; it's kind of sad that Canon's touting that this is the first of its PowerShots to include a panorama mode.

On the upside, it does have the same 7fps (with autofocus and autoexposure) continuous-shooting speed and nice electronic viewfinder as the M5, plus it should have the Dual Pixel CMOS' generally excellent autofocus. And it has what many M5 users have been clamoring for: a more dust-and-weather resistant body, though it's only "drip" resistant. Canon will offer a waterproof housing for the camera, which it never offered for it's APS-C dSLRs or mirrorless models.

...and it makes complete sense 

The lesson we've all learned about the majority of consumer interchangeable-lens buyers is that they rarely interchange. They use whatever kit lens came with the camera, usually an 18-55mm f3.5-5.6 or a similarly slow all-in-one zoom (ranges vary), basically turning a dSLR or mirrorless into an oversize compact. So, from that perspective, this camera makes complete sense. 

Plus, Canon lags behind the rest of the world with its overpriced mirrorless models. So why not take all the important stuff from the M5 mirrorless, stick it in the slightly more M5 users have been clamoring for, stick a fixed lens on it and offer it for the same price? (An artificially similar price, since Canon only offers an 18-250mm f3.5-6.3 lens kit for the M5; it would be a lot cheaper with a comparable 18-55mm zoom.)

However, I am not a huge fan of the Dual Pixel CMOS' photo quality, so the move to APS-C versus Panasonic's somewhat smaller but excellent sensor or Sony's 1-inch-RX series powerhouses, doesn't do much for me in this context, especially given the slow lens and unimpressive feature set. And don't forget the meh 200-shot battery life!


Canon PowerShot G1 X Mark III

Sensor effective resolution

24.2MP Dual Pixel CMOS

Sensor size

22.3 x 14.9 mm

Focal-length multiplier




Sensitivity range

ISO 100 - ISO 25600

Lens (35mm equivalent)




Closest focus

4 in/10 cm

Burst shooting


29 JPEG/n/a

(9fps with exposure and focus fixed on first frame)


(mag/ effective mag)


0.4 in/10mm

2.4m dots

100% coverage

Hot shoe



On-pixel phase-detection

AF sensitivity


Shutter speed

1/2,000 to 30 secs; bulb



Metering sensitivity


Best video

H.264 QuickTime MOV

1080/60p, 30p, 24p



Manual aperture and shutter in video


Maximum best-quality recording time

9:59 mins

Optical zoom while recording


Clean HDMI out





3 in/7.5 cm

Articulated touchscreen 

1.04m dots

Memory slots

1 x SDXC

Wireless connection

Wi-Fi, NFC, Bluetooth



Wireless flash


Battery life (CIPA rating)

200 shots

(1,250 mAh)

Size (WHD)

4.5 x 3.1 x 2.0 in

116 x 78 x 51 mm

Body operating weight

14.1 (est.) 

399 g (est.)

Mfr. price



Release date

November 2017