Canon G1 X Mark III vs Sony RX100 III: A Deep Dive Into Two Large Sensor Compacts

When it comes to large sensor compact cameras, Canon and Sony have long held distinct positions catering to enthusiasts who crave high image quality in pocketable form factors. The Canon PowerShot G1 X Mark III and Sony Cyber-shot DSC-RX100 III are prime examples of this category, released three years apart yet both commanding respect for their capabilities. Having spent extensive time testing both models across genres - from wildlife to street photography - I’m here to unpack how these cameras compare in real-world photography and videography, peeling back specs and diving deep into user experience.

Whether you’re upgrading from entry-level compacts or seeking a lightweight second camera for professional work, this comparison will highlight practical differences, strengths, and limitations to help inform your choice.

Size, Build, and Handling: Ergonomics in the Palm of Your Hand

The feel of a camera in hand is often underestimated yet shapes the entire shooting experience. Both these cameras aim to balance portability with robust controls but take different approaches due to design eras and philosophies.

At 115 x 78 x 51 mm and weighing 399 grams, the Canon G1 X Mark III epitomizes a “large” compact camera, featuring a substantially larger APS-C sensor beneath the hood. Its body offers a comfortable grip, and the robust magnesium alloy chassis paired with weather sealing gives it an air of reliability when shooting outdoors or in inclement conditions.

The Sony RX100 III, more pocket-friendly at 102 x 58 x 41 mm and 290 grams, appeals to photographers prioritizing discretion and ultra-portability. Its body is predominantly magnesium alloy and plastic, lacking weather sealing, but impressively solid given its size. It slips easily into a jacket pocket or small bag - a great tactical advantage for street shooters or travelers running light.

One significant ergonomic edge the Canon holds is the fully articulated touchscreen LCD, offering 1040k dots of resolution and touch-to-focus/command functionality. The Sony opts for a tilting screen (up/down), with a slightly higher pixel count at 1229k dots but no touchscreen capabilities. This difference impacts how you frame and navigate menus, especially for video shooting or awkward angles.

Control-wise, the Canon gives greater access and tactile feedback. Its strategically placed dials and buttons allow quick ISO adjustments, aperture control, and custom function assignment - a must for rapid shooting scenarios. Sony’s streamlined approach emphasizes minimalism but can slow you down when fumbling through menus or toggling modes.

In short: If you prize hand comfort, robust handling, and weather resistance, the Canon G1 X Mark III excels. For ultra-compact portability and discreet shooting, the Sony RX100 III shines.

Sensors and Image Quality: Bigger Isn’t Always Better, but Probably Is

At the heart of any camera lies its sensor. This is the playground where light is captured and transformed into images. Canon equips the G1 X III with a 24MP APS-C CMOS sensor sized at 22.3x14.9 mm, while Sony’s RX100 III offers a 20MP 1-inch BSI-CMOS sensor measuring 13.2x8.8 mm - about a third of Canon’s sensor area.

The larger sensor of the Canon provides inherently superior image quality, particularly in noise performance, dynamic range, and color fidelity. In my calibrated tests, the Canon’s images retain cleaner detail up to ISO 3200, with usable files even at ISO 6400 and above, whereas the Sony shows visible noise starting at ISO 800-1600, typical for 1-inch sensors of its generation.

Chris Nichols, a colleague and sensor expert, often says bigger sensors collect more photons, translating into higher signal-to-noise ratios and broader tonal gradations - making this a clear advantage for the Canon in demanding lighting.

However, it’s important not to dismiss Sony’s RX100 III outright; its BSI (backside illuminated) sensor architecture helps maximize light gathering, improving low light clarity over older 1-inch sensors. Color depth, as measured on DxO Mark, places the RX100 III at 22.4 bits versus Canon’s unquantified but strongly APS-C competitive output.

Sony also supports a wider variety of aspect ratios (1:1, 4:3, 3:2, 16:9), whereas Canon sticks to 3:2.

Bottom line on image quality: Canon G1 X III is superior for critical image quality needs, especially in low light and high dynamic range scenes. Sony RX100 III remains an exceptionally capable compromise for enthusiasts who must prioritize size but still want a big step up from smartphones or smaller compacts.

Autofocus Systems and Performance: Locking Focus When It Counts

Nothing kills a shot faster than missed focus. Autofocus performance is crucial across genres but particularly in wildlife, sports, and candid street photography.

The Canon G1 X Mark III uses a hybrid AF system with 49 focus points combining phase-detection and contrast-detection autofocus methods. This gives the camera quick and reliable locking, even in challenging lighting and with subjects in motion. The inclusion of face detection further helps portrait photographers nail critical focus on eyes, essential for expressive, tack-sharp portraits.

In my field tests tracking birds in flight and children at play, Canon’s AF was fast, accurate, and dependable without hunting or lag.

Conversely, the Sony RX100 III deploys a 25-point contrast-detection AF system, lacking on-sensor phase detection. This puts it at a slight disadvantage for continuous AF tracking and fast-moving subjects, although for static or slow-moving subjects it works well. Face detection exists but the lack of eye-detection AF means portraits require more manual finesse.

Tracking performance is also supported by slightly faster burst shooting - 10 fps with Sony versus 9 fps with Canon - helpful for fleeting moments in sports or wildlife.

Summary on autofocus: Canon G1 X III’s hybrid AF system outperforms Sony RX100 III’s contrast-only AF in speed and tracking accuracy, making it superior for action-oriented photography. Sony is still competent for general use but shows its age under demanding conditions.

Display, Viewfinder, and User Interface: Seeing Your World

Both cameras equip electronic viewfinders (EVF), a key feature for high-quality compacts.

• Canon’s EVF offers 2.36 million dots resolution and 100% frame coverage but lacks measured magnification data.
• Sony provides a 1.44 million dots EVF, 100% coverage, and a 0.59x magnification.

The Canon’s EVF delivers a crisp and clear preview image, making manual focusing and composition straightforward. In contrast, Sony’s smaller EVF lacks the sharpness and size for easy use with glasses, but it remains functional thanks to effective color rendition.

For rear LCD displays:

The Canon’s 3-inch fully articulated touchscreen with 1040k dots allows flexible shooting angles and intuitive touch focus/navigation - very handy for macro, video, and self-portrait styles. Meanwhile, the RX100 III’s tilting 3-inch screen is higher resolution but lacks touch, which might frustrate users accustomed to smartphones or tablets.

Both cameras have built-in flashes, with Canon supporting external flashes and slow-sync modes, whereas Sony’s internal flash is purely basic and non-expandable.

User interface-wise, Canon’s menu system is more traditional and detailed, suiting enthusiasts needing quick access to manual controls. Sony’s menu is simpler but lower on customization.

Lens Systems and Versatility: Fixed Zoom Considerations

Both cameras feature fixed lenses with respectable focal ranges but different apertures:

• Canon G1 X III: 24-72 mm (equivalent), 3x zoom, max aperture f/2.8-5.6
• Sony RX100 III: 24-70 mm, 2.9x zoom, max aperture f/1.8-2.8

Sony’s much wider aperture at the wide end (f/1.8 vs f/2.8) offers superior low-light throughput and shallower depth-of-field, great for portraits and evening shooting. Canon’s lens offers more telephoto reach but slower maximum aperture, compromising performance in dim environments and bokeh quality.

In practice, the RX100 III’s lens produces beautifully smooth bokeh and superior subject isolation at wide angle, ideal for street and portraiture.

The Canon is a more versatile all-round zoom for landscapes and travel, while Sony’s brighter lens aids night and indoor photography.

Neither camera supports lens changes, obviously, which limits system flexibility but ensures compactness.

Stabilization, Burst Rates, and Shutter Performance

Image stabilization is optical in both, helping reduce blur from hand shake.

Canon’s G1 X III’s 5-axis optical IS is very effective, especially combined with the large sensor. It’s particularly useful in macro and low shutter speed scenarios. Sony’s RX100 III has optical steady shot but lacks multi-axis compensation, making it slightly less effective for video and slow shutter use.

Burst shooting performance edges in favor of Sony at 10 fps versus Canon’s 9 fps, but real buffer depth limits extended bursts.

Shutter speeds are equal, maxing at 1/2000 sec, which is standard for compacts but a bit limiting for bright environments or super-fast action photography.

Video Capabilities: Full HD Familiars but No 4K

Neither camera offers 4K video recording, a notable omission given Sony’s RX100 IV and Canon’s newer models.

• Canon G1 X III records 1080p at 60p with 35 Mbps in MP4 (H.264)
• Sony RX100 III supports 1080p at 60p/60i/24p and 720p up to 120 fps, with formats including AVCHD, MPEG-4, and XAVC S

Sony’s expanded frame rates and video codec support make it stronger for casual slow-motion and UHD chroma subsampling, but the lack of external microphone inputs in both cameras limits audio quality control.

Neither camera has headphone jacks, so monitoring sound live isn’t possible - a real shame for serious videographers.

The Canon’s fully articulated touchscreen aids videographers in framing and focus, overshadowing Sony’s non-touch tilting screen.

Battery Life and Storage Media

Battery longevity is a common concern in compact cameras.

• Canon G1 X III rates ~200 shots per charge with a built-in battery - relatively modest considering large sensor and power-hungry features
• Sony RX100 III offers about 320 shots per charge using replaceable NP-BX1 batteries, a more generous allowance for longer shooting days

Storage wise, both use single SD card slots compatible with SD/SDHC/SDXC. Sony also supports Memory Stick Pro Duo - less common nowadays.

Wireless Features and Connectivity

Both models provide built-in Wi-Fi and NFC for quick pairing with smartphones or tablets for image transfer and remote control.

Canon includes Bluetooth support, enabling persistent connections for GPS tagging through smartphone apps - handy for travel photographers tracking location data.

Physical connectivity includes USB and HDMI in both; Canon uses a standard USB interface while Sony uses USB 2.0 (slower but adequate for transfers).

Real-World Photography Tests Across Genres

To further ground this comparison in practical use, I’ve tested these cameras across popular genres, blending controlled lab tests with fieldwork.

Canon G1 X III front Canon G1 X III screen back Sony RX100 III front Sony RX100 III screen back

Portrait Photography

Canon’s larger sensor excels at rendering natural skin tones and subtle gradations. With 49 AF points and face-detection, portraits come out sharp with pleasing bokeh, despite the lens’s slower aperture. Sony’s faster lens offers better shallow depth of field and creamy backgrounds but requires more care to focus due to fewer AF points.

Landscape Photography

Canon’s APS-C sensor delivers better dynamic range, preserving shadow detail and highlight recovery in high contrast scenes. Its weather sealing encourages worry-free outdoor use. Sony’s 1-inch sensor and lens combination still creates excellent wide-angle crispness but lacks the latitude to rescue blown highlights or deep shadows.

Wildlife Photography

The Canon’s AF hybrid system and higher burst speed shine here, with more consistent focus tracking. Sony is at a disadvantage but usable with slower subjects.

Sports Photography

Canon again leads due to better AF tracking and handling, though neither camera is optimized for professional sports work.

Street Photography

Sony’s compact size and quiet shooting lend themselves well to street photography, with discreet handling and a bright wide aperture facilitating low light candid shots.

Macro Photography

Canon’s close-focusing distance of 10cm combined with IBIS enables sharp macro captures. Sony focuses as close as 5cm but may suffer without robust stabilization, making Canon preferable overall.

Night and Astro

Canon’s low noise at high ISO and longer exposure capabilities benefit night and astro photography, despite no full bulb mode. Sony’s brighter lens helps but sensor noise rises quickly.

Video Shooting

Sony’s frame rate and codec options offer more versatility for casual video shooters, though Canon’s touchscreen and IS smooth work better ergonomically.

Travel Photography

Both compact cameras suit travel well, but Canon’s weather sealing and articulating screen make it the more rugged choice, while Sony edges on weight and compactness.

Professional Work

Canon’s robust file quality, weather resistance, and better AF support integrate better into workflows demanding reliability. Sony serves well as a lightweight “backup” or snapshot camera.

Performance Scores and Overall Ratings

Aggregated lab and field test scores reflect the Canon’s higher image quality, AF prowess, and build quality. Sony scores well for portability and lens brightness but trails in core shooter metrics.

The Verdict: Who Should Buy Which?

• Choose the Canon PowerShot G1 X Mark III if...

  • You want larger APS-C image quality in a compact form.
  • You frequently shoot portraits, landscapes, wildlife, or macro.
  • You need weather sealing and robust handling.
  • You prefer touchscreen controls and an articulating display.
  • You’re willing to invest in a higher price tag (around $1300).

• Choose the Sony RX100 III if...

  • Portability and low weight are your top priorities.
  • You shoot street, travel, or casual portraits.
  • You want a bright lens for shallow depth of field and low light.
  • Your budget maxes out near $750.
  • You’re comfortable with fewer manual controls and slower AF tracking.

Summing Up: Two Excellent but Differently Focused Large Sensor Compacts

While falling under the same category, the Canon G1 X Mark III and Sony RX100 III clearly address different photographic mindsets. Canon’s larger sensor, weather sealing, and control-rich body make it a semi-professional tool for serious imaging, at the cost of size and price. Sony’s RX100 III affords a superb balance of performance, optics, and pocketable convenience, excellent for enthusiasts on the go who prioritize size and lens speed over absolute image quality.

Both cameras remain relevant choices depending on your priorities and style of photography. Testing both in hand and in the field delivered insights that specs alone cannot convey, reinforcing the value of hands-on evaluation when investing in specialized photographic gear.

Thank you for journeying through this detailed comparison - I hope it empowers your decision-making with clarity and confidence. As always, happy shooting!