Sony A7 III vs Sony A6700: The Expert’s Guide to Choosing Your Next Mirrorless Camera

When it comes to investing in your next mirrorless camera, Sony's Alpha line consistently offers compelling options. The Sony A7 III and the newly launched Sony A6700 are two standout models catering to slightly different users but both bring impressive technology to the table. After extensive hands-on testing and careful analysis, we’re here to help you decode which camera aligns best with your photographic ambitions - whether you’re a seasoned professional or an enthusiastic hobbyist seeking to step up your game.

We’ll break down each camera’s core strengths, performance across popular photography disciplines, technical innovations, and usability - with an honest, detailed approach that respects your creative journey.

First Impressions: Size, Design, and Handling

Before diving into the specs and image quality, the physical feel and design of a camera often determine how comfortable you are during extended shoots.

The A7 III’s more substantial, SLR-style body gives you a reassuring grip and a sense of robustness that’s well-suited for professional use. In contrast, the A6700's compact, rangefinder-style design makes it more portable and discreet, great for travel and street photography without weighing you down.

The fully articulated screen on the A6700 offers more freedom for creative angles and vlogging, while the A7 III’s tilting screen is a bit more limited but still versatile.

Ergonomically, the A7 III features a slightly deeper grip and more traditional layout, ideal for those accustomed to DSLR-style handling. The A6700 is sleeker but maintains good control placement, fit for quick shooting and spontaneous moments.

Sensor and Image Quality: Full Frame vs APS-C

At the heart of any camera’s image-producing power is its sensor. Here, the A7 III employs a full-frame 24MP BSI-CMOS sensor, while the A6700 uses a 26MP APS-C (1.5x crop) BSI-CMOS sensor.

What Does This Mean in Practice?

• Dynamic Range and Noise Performance: The full-frame sensor of the A7 III offers a significantly larger sensor area (852 mm² vs 366.6 mm²), resulting in superior dynamic range and low-light capabilities. Our lab and real-world tests confirm the A7 III can reliably deliver cleaner images at high ISOs, excellent shadow recovery, and richer color depth.

• Resolution and Detail: Both cameras provide around 24-26 megapixels, which is ample for most photography needs. The A6700’s slightly higher resolution benefits cropping and APS-C-sized print output but can’t fully match the tonal gradation subtlety of the A7 III.

• Crop Factor: The A6700’s 1.5x crop extends the apparent focal length of lenses, useful for wildlife or sports where extra reach is desirable without additional lenses. However, this crops into the image circle and reduces the sensor’s light gathering.

Summary: For ultimate image quality, especially in challenging lighting or when maximum detail and dynamic range are priorities, the A7 III holds a clear advantage. The A6700 offers more telephoto reach and excellent quality for its sensor size but can’t fully rival full-frame performance.

Autofocus Systems: Speed, Accuracy, and Tracking

Both cameras boast advanced hybrid AF systems with a high count of phase detection points, but there are critical differences impacting real-world focusing reliability.

The A6700 slightly edges out with more AF points and faster continuous shooting speed, benefiting sports and fast wildlife photography. Its autofocus benefits from newer algorithms enabling more confident subject tracking and eye detection in video mode at 4K 120p.

The A7 III’s AF system has already proven its reliability across genres since 2018, delivering silky-smooth continuous AF for portraits and high accuracy in challenging light and low contrast scenarios.

Whether you prefer the tried-and-true autofocus of the A7 III or the subtly enhanced, modernized system of the A6700 depends on your shooting style. Both will lock on eyes effectively and track moving subjects well.

Burst Shooting and Buffer Depth

For capturing fast action - sports, wildlife, or spontaneous street moments - speed and buffer size make all the difference:

While the A6700 delivers a slightly faster 11fps burst, its buffer depth in RAW mode is roughly half that of the A7 III. In practice, this means the A7 III allows longer sequences without slowdown, essential for events or wildlife sequences where missing a decisive moment isn’t an option.

Build Quality and Environmental Resistance

Both cameras feature weather-sealed bodies, a must for professional reliability and durability.

• The Sony A7 III’s body is constructed from robust magnesium alloy with ample sealing against dust and moisture, built to withstand rigorous usage demands.

• The A6700 also offers sturdy weather resistance, though its more compact size reduces the structural heft somewhat.

Neither camera is fully waterproof or shockproof, so care is needed in extreme conditions or impact.

Screen and Viewfinder

Assessing the screen and EVF experience is vital for both composition and image review:

The A6700’s fully articulated touchscreen caters especially well to vloggers, content creators, and photographers shooting at challenging angles. The slightly higher resolution screen also provides crisp image review.

The A7 III’s tilting screen is adequate for most uses but lacks the full flip-out convenience.

Both electronic viewfinders deliver sharp, 100% coverage and minimal lag, critical for precision framing and exposure evaluation in fast-paced shooting.

Lens Selection and Ecosystem

While both models utilize Sony’s E-mount system, lens selection varies because of sensor formats:

Sony’s lens ecosystem is one of the most extensive and mature on the market. The A7 III taps into the full-frame collection, including top-tier G Master primes and zooms optimized for high resolution.

The A6700 benefits from an even larger selection including many APS-C-specific optics, which tend to be smaller and less expensive, providing more portability and budget options.

If you already own Sony glass, check whether your preferred lenses fit your intended sensor size. Full-frame lenses on the A6700 operate with a crop factor, occasionally affecting wide-angle coverage.

Battery Life and Storage

When planning for longer shoots or travel, battery endurance and storage options matter.

The dual card slots in the A7 III provide significant advantages for backup and overflow during critical professional usage - ensuring your images are doubly protected.

Battery life is solid for both cameras, slightly favoring the A7 III due to its bigger battery capacity, though real-world use varies depending on video or continuous shooting.

Video Features: Resolution and Flexibility

Video capabilities have become crucial for many creatives. Here’s how these cameras stack up:

Sony A7 III front Sony A7 III screen back Sony A6700 front Sony A6700 screen back

The A6700 noticeably advances video features, supporting 4K at up to 120fps with next-generation H.265 (HEVC) encoding, which offers better compression efficiency and image quality. Its fully articulated screen also makes vlogging and self-shooting easier.

The A7 III, while solid with 4K video at 30p and 1080p slo-mo, feels more oriented towards still photographers who occasionally shoot video.

Specialized Uses Across Photography Genres

To provide a practical lens on which camera excels where, we looked at key genres:

Overall Performance and Value Assessment

Taking all features into account, here is a snapshot of their scores based on comprehensive tests combining lab results and real-world use:

Summing It Up: Which Sony Mirrorless Fits You Best?

Choose the Sony A7 III if:

• You prioritize ultimate image quality, especially in portraits, landscapes, or low light.
• Your work demands professional reliability, including dual card slots and superior build.
• You want full access to the full-frame lens ecosystem and extended dynamic range.
• You require longer buffer depth for action sequences.
• You occasionally shoot video, but mainly prioritize stills.

Lean toward the Sony A6700 if:

• You want a lighter, more compact body ideal for travel, street, and wildlife photography.
• You need cutting-edge video features such as 4K 120fps and a fully articulating screen.
• You appreciate the extra telephoto reach provided by the APS-C crop factor.
• Your budget is more constrained but you still want fast autofocus and strong performance.
• You favor vlogging or content creation that benefits from a selfie-friendly flip-out screen.

Final Advice for Your Next Steps

Both cameras represent excellent investments, but your choice depends on shooting style, priorities, and budget. Here’s how you can get the most out of this guide:

• Test Them In-Person: Ergonomics and handling are subjective. If possible, visit a store or rental service to shoot with both.
• Consider Lenses: Factor in what lenses you own or plan to buy, and the impact of sensor size on focal lengths.
• Check Accessories: From gimbals to microphones to ND filters, plan for the gear that complements your shooting style.
• Budget for Your Growth: Don’t forget to budget not just for the camera but for upgrades like faster cards or batteries.
• Explore Tutorials: Both cameras have large communities and resources to help you master their features.

Your Creative Journey Starts Here

Sony’s A7 III and A6700 are powerful tools that expand creative possibilities. Whether chasing fleeting wildlife in the wild, shooting cinematic video, or crafting stunning portraits, picking the right camera is the first step toward future growth. Embrace your vision, experiment boldly, and harness the best technology tailored to your style.

Ready to get started? Check out trusted reseller options, look for bundles that include lenses or accessories, and dive into tutorials designed to accelerate your mastery of these cameras.

We hope this detailed comparison empowers you to feel confident in your choice - because the best camera is the one that brings your ideas to life with clarity and joy.

Thank you for joining us in this in-depth look at the Sony A7 III and Sony A6700. For more expert reviews and buying guides, stay tuned to our channel.