Canon G7X Field Test Part I
Canon G7X Field Test Part I
The contender for Sony's throne goes toe-to-toe in the real world!
By Michael Tomkins | Posted: 12/18/2014
It's no secret that Sony's RX100-series enthusiast compact cameras, with their pocket-friendly bodies and larger-than-average sensors, have been among my favorite cameras in the last couple of years. After two years with no direct competition for the RX100 series, Sony finally has a rival in the form of the Canon G7X, and you'd better believe I wanted to get my hands on one posthaste!
In part, my eagerness to review the Canon G7X comes thanks to the fact that in almost the same footprint as the flagship RX100 III, it offers a clear advantage over Sony's camera in terms of telephoto reach. (Yet at the same time, it provides the same f/1.8-2.8 maximum aperture across the zoom range.) On paper at least, that's a pretty big deal, because it allows you to bring your subjects quite a bit closer -- handy when you can't frame with your feet.
But how would the Canon G7X and its impressive-sounding lens perform in the real world? To find out, I took Canon's first entry in the large sensor, pocket camera out for a side-by-side shoot with its main rival, the Sony RX100 III, as well as the even larger-sensored (but most definitely not pants-pocket friendly) Panasonic LX100.
A pocket-friendly camera with good handling
On taking the Canon G7X out of its packaging and comparing it side-by-side with the Sony RX100 III, RX100 II and RX100, all of which I was fortunate to have at the same time, I found myself pretty amazed by what Canon has managed with this ambitious design.
Sure, in a lot of ways the control layout is very similar to that of the RX100-series cameras, but then there's only so much you can do with a small, pocket-friendly chassis with a lens on the front. But in a body that's barely distinguishable from the Sony RX100 III in terms of size, Canon has managed to pack in most of that camera's features other than its popup electronic viewfinder. Yet somehow, the G7X sports a lens with the same 24mm f/1.8 wide angle, but almost 50% greater telephoto reach, taking you out to a handy 100mm f/2.8 telephoto.
And Canon also gives you a dedicated exposure compensation dial, a photographer-friendly touch that makes it very quick to tweak exposure on the fly. It sits beneath the Mode dial, stacked wedding cake-style, and has a firm enough click detent that the dial is never accidentally bumped. Wherever you set your exposure compensation, you can be confident that it will still be set the same the next time you pull your camera out of your pocket or bag.
The ring around the lens, too, has a good click detent. It's a compromise -- and the opposite one to that of Sony's clickless lens ring -- but there's no denying that it feels great when adjusting the lens' aperture using the ring. Sony's free-spinning lens ring, by contrast, feels very detached and fly-by-wire when adjusting aperture. The downside of Canon's choice is that if you use the ring for focus adjustment, and a significant adjustment is needed, there's a whole lot of clicking as you spin the dial to bring the point of focus nearer or further.
More zoom to bring subjects closer
As you can probably tell, my favorite feature of the Canon G7X compared to its rivals is its significantly greater zoom reach. With the Sony RX100 series, I was happy to put up with a relatively limited zoom range, simply because there was no competing camera with a similar body and sensor size, but a more powerful zoom lens. That's no longer the case.
There's no question about it -- having access to a more powerful telephoto means you can bring your subjects closer, and so you don't have to be right in the middle of the action to capture it. And that it does so while actually offering a brighter aperture across most of the zoom range makes this an even more impressive feat.
Starting at the 24mm-equivalent wide-angle position, both cameras provide a maximum aperture of f/1.8. Zoom to the 28mm position, though, and the RX100 III's aperture falls to f/2.5, while the Canon G7X still offers f/2.0. At 35mm, Sony has already dropped all the way to f/2.8, where it will remain until the telephoto position, while Canon has an f/2.2 aperture.
The G7X stops down to f/2.5 by 50mm, and doesn't finally reach f/2.8 until you get to somewhere around 56mm. From there, its aperture remains unchanged all the way to the 100mm-equivalent telephoto, matching Sony's brightness but with significantly more reach.
Of course, if the RX100 III's lens doesn't bring your subjects close enough, you can simply crop the image -- and with its high 20.2-megapixel resolution, you can do quite a bit of cropping while still retaining a reasonable print size. But that's true of the Canon G7X as well, given that it shares the same resolution.
Top -- 24mm-equivalent, 1/60 sec. @ f/5.6, ISO 200
Bottom -- 100mm-equivalent, 1/200 sec. @ f/5.6, ISO 500
There are no two ways about this: If you want the brightest possible aperture in a pocket camera with a 1"-type sensor, and you want to frame your subjects as tightly as possible, the Canon G7X is your best bet. And as I wandered around downtown Knoxville, shooting with these cameras side by side, I found shooting with the G7X rather liberating.
Compromises to achieve a more powerful zoom
That's not to say that it's perfect, however. Canon is subject to the same laws of physics as any other manufacturer, and there are some definite compromises that have been made to achieve this impressive lens. That becomes most startlingly obvious when you open a Canon G7X raw file shot at or near wide-angle in an application that doesn't automatically provide Canon's default lens corrections.
Apps like Adobe's Photoshop Lightroom and Camera Raw will provide those corrections even at their default settings, so if you restrict yourself to those, you might not notice this aspect of the design. (Or at least, you may notice its aftereffects -- some pretty dubious image quality in the corners towards wide-angle -- but not their underlying cause.)
The reason becomes blindingly obvious in programs like FastRawViewer, my image culling app of choice, however. Look at an uncorrected raw file from the Canon G7X shot near wide-angle, and you realize that the lens' image circle doesn't cover the entire sensor area.
It's normal for uncorrected raws from pocket-friendly, large-sensor cameras to have strong distortion and corner vignetting, but this is nevertheless a pretty extreme example. To provide a usable image, it has to first be stretched to reach the corners -- and that means each pixel captured by the sensor in the corners ends up spanning a greater area in the final image.
That's done automatically in-camera for JPEGs, and for raw files most mainstream apps will also handly it transparently for you. There's no getting around the fact that image quality is degraded in the corners, though, with a greater reduction in sharpness than we're used to seeing. If you're shooting a relatively central subject against a nicely-blurred background, you won't notice. If your image has strong detail even in the corners -- a landscape, say -- it can be pretty obvious at larger print sizes if you're paying attention.
I also noticed almost immediately when shooting a few random macros of objects on my desk, shortly after first unpacking the camera, that significant flare and reduced contrast can rear their head, giving macros a rather lo-fi look that's noticeable even on the camera's own LCD, and even more so once you get images on a larger display, or print them out.
No viewfinder and a less versatile LCD
Physically speaking, I also noticed pretty quickly that the Canon G7X had a couple of shortcomings, compared to the similarly-sized Sony RX100 III. First, it has a rather less sophisticated articulation mechanism for the LCD monitor.
Neither camera has a full tilt/swivel design, but Sony's can at least tilt both upwards and downwards, allowing for shooting from the hip, low to the ground, or over your head. Canon's top-mounted hinge only allows for an upwards tilt, so you can't use it for shooting over your head.
Or at least, doing so will require holding the camera upside down, and pressing the shutter button with your thumb. That doesn't present the best of ergonomics, but it's better than missing the shot altogether because you couldn't frame it.
Perhaps more importantly, though, there's also no electronic viewfinder, nor any way to attach an external accessory finder. I don't find myself using the Sony RX100 III's built-in, popup viewfinder that often, but when I do, it's typically because it's difficult to see the screen well enough to frame or review my shot because of harsh sunlight.
The Canon G7X's screen is just a little less bright than that of the Sony, so if anything, it's slightly more prone to the problem -- but provides no solution other than trying to shade the screen with your hand.
A mixed bag in terms of performance
The Canon G7X turns in something of a mixed performance compared to the Sony RX100 III, showing good speed in some respects, and less so in others. Both cameras were outperformed by the Panasonic LX100, but that's perhaps an unfair comparison given its significantly greater size.
Out of the box, the Canon G7X shot image bursts about one-third faster than the RX100 III, but that's in JPEG mode and with autofocus enabled between shots. Disable autofocus, and the G7X improves still further, but not by as much as the RX100 III, which in turn was now one-third faster than its rival. And the Sony also provided much greater buffer depths, although both cameras managed dozens of shots before slowing in JPEG mode.
The real problem came with raw shooting enabled, either as the sole file type or when combined with simultaneous JPEG capture. Here, performance plunged from pretty good to absolutely pedestrian, managing less than a frame per second. By contrast, the Sony RX100 III was now some three to six times faster, depending on whether autofocus was enabled. This, clearly, is not a camera a raw shooter will enjoy.
The Canon G7X's autofocus performance was also not quite as swift as that of the RX100 III, although here the difference was much more modest. Both cameras seemed about equally reliable at managing to achieve a focus lock, handling relatively low light before failure to achieve a lock became frequent. (And even here only with more distant subjects beyond the reach of the AF illuminator.)
However, the Canon G7X was noticeably faster to start up and grab a quick snapshot when an unexpected photo opportunity presented itself than was the Sony RX100 III. I also found Canon's menus quicker to navigate than those of the Sony, which spreads its options across many separate pages, causing lots of side-to-side scrolling through tabs, then up-and-down scrolling to get to the option you want, whereas with the Canon I simply had to choose a single tab and then hold the down-arrow until I got to the right option.
On balance, I think I'd probably give this one to the Canon G7X, of the pair, but only if you're a JPEG shooter. If you shoot raws more than just very occasionally, you'll want the Sony RX100 III instead.
Generous creative options, with one bizarre exception
In terms of their creative options, both the Canon G7X and Sony RX100 III struck me as pretty similar to each other, offering the ability to bracket exposures, tweak colors, contrast and sharpening to your liking in JPEG mode, and offering built-in ND filters as well as tools to control dynamic range. One omission on the Canon surprised me a bit, however, as it's so all-pervasive these days.
While the Sony RX100 III and Panasonic LX100 both offer consumer-friendly panorama functions that rattle off a burst of shots as you sweep the lens across your subject while holding the shutter button, and then automatically stitch them in camera to create the finished panoramic image, there's no such tool in the Canon G7X. If you want to shoot panoramas, you'll have to do so completely manually with this camera, capturing each shot in succession and then manually stitching them on your computer.
Will you get more control that way, and probably a better final result? Yes, but you'll also have to put a lot more work into it -- and you could've gained that control by simply not using the panorama function of the competing camera. But if all you want is a quick, spontaneous panorama without any hassle, that's simply not an option here.
It's a bit of a shame, really, in a camera that I'd imagine more than a few less experienced consumers will pick up. I'd have expected it to be missing from the Panasonic LX100, whose controls make clear that this is a camera for experienced photographers, but not from the G7X. In fact, I found myself browsing the PDF user guide on my phone in the middle of downtown Knoxville when a panorama opportunity presented itself, absolutely convinced I must have been missing something. Sadly, I wasn't.
Attractive color from the Canon, but not as much detail as rivals
And so we come to the image quality comparison, with the proviso that so far I've only compared the two cameras in daytime shooting through to the end of sunset.
For the most part, I found Canon's color rendition more pleasing, and closer to how I remembered the actual scenes. Sony's white balance system, in particular, seemed to want to neutralize the golden hour warmth of my photos, where Canon retained just enough of that warmth to match my memory.
In terms of exposure, there really wasn't much in it. Both cameras exposed similarly most of the time, and neither seemed to have any problems, except with predominantly dark or light subjects that most any camera will struggle with a little.
Images from the Sony seemed to have just slightly better sharpness at the center of the frame, and especially when shooting wide open, the Canon G7X suffered from rather weak corners due to the stretching required to correct for its slightly curtailed image circle.
In this department, I definitely have to give the edge to Sony so far, but that's perhaps just a little unfair to Canon, given that they're packing in so much more zoom range. Still, both cameras have the same wide angle, and Sony definitely provides better results at this end of the zoom range.
And there's more still to come...
I've yet to shoot much at higher sensitivities, so I'll reserve judgement in this area for my next Field Test. However, my initial gut feeling from the few high ISO shots I've tried was that the Canon G7X seems to show more chroma noise in its images than does the RX100 III. More on that, though, once I've had the opportunity to make a more detailed comparison of the two cameras in low light. I'm also planning to compare movie capture.
If there's anything in particular that you'd like to see me take a look at, drop me a note in the comments below, and I'll do my best to answer your requests, too!