Sony a7 III Full-Frame Mirrorless vs Sony Alpha a6700 APS-C Mirrorless Camera: Spec Comparison
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When comparing the sony a7 iii full frame mirrorless vs alpha a6700 aps c mirrorless, you see two distinct approaches to image capture. Both cameras deliver high-resolution stills and robust autofocus systems for serious photography. The main difference lies in the sensor size. The a7 III uses a larger full-frame sensor, while the a6700 relies on an APS-C format. This choice affects image quality, lens options, and overall camera size. You need to decide which form factor and sensor type best fit your workflow.
Key differences
| Aspect | Sony a7 III Full-Frame Mirrorless Camera | Sony a6700 APS-C Mirrorless Camera |
|---|---|---|
| Sensor Format | Full-frame | APS-C |
| Sensor Resolution | 24.2MP | 26.0MP |
| Video Resolution | not listed | 4K 120p |
| Image Processor | not listed | BIONZ XR |
| Weight | 1.43 pounds | 14.5 ounces |
Which one should you choose?
Choose Sony a7 III Full-Frame Mirrorless Camera if
- You prioritize a larger full-frame sensor for better low-light performance and dynamic range.
- You need a camera body that weighs over a pound for a substantial grip feel.
- You want a proven autofocus system with 693 phase-detection points covering 93% of the frame.
Choose Sony a6700 APS-C Mirrorless Camera if
- You want to record high-frame-rate 4K video at 120p for slow-motion effects.
- You prefer a lighter and more compact camera body for easier portability.
- You value the latest BIONZ XR processor for faster subject recognition and tracking.
Verdict: Choose the a7 III if you need a full-frame sensor for superior image quality and dynamic range in still photography. Pick the a6700 if you require advanced video capabilities like 4K 120p and a lighter, more modern body. Your decision should depend on whether you prioritize sensor size or video performance and portability.
Sensor Size and Resolution Tradeoffs
sensor format
The Sony a7 III uses a 35mm full-frame sensor, while the Sony a6700 features an APS-C format. This difference in physical size affects light gathering and depth of field. A larger sensor generally provides better low-light performance and shallower background blur. The a7 III’s full-frame design is ideal for portraits and landscape work where background separation matters. The a6700’s smaller APS-C sensor offers a crop factor, which extends the effective reach of telephoto lenses. You choose based on whether you prioritize sensor size or lens versatility.
resolution
Both cameras offer high pixel counts suitable for detailed images. The Sony a7 III provides 24.2 megapixels from its back-illuminated sensor. The Sony a6700 offers 26.0 megapixels from its Exmor R back-illuminated CMOS sensor. The a6700 has a slight edge in pure resolution, capturing more detail in well-lit scenes. However, the a7 III’s larger sensor size often compensates for the lower megapixel count with better noise handling. For most users, both resolutions are sufficient for large prints and cropping. The difference is marginal in everyday shooting conditions.
video resolution
Video capabilities differ significantly between these two models. The Sony a6700 supports 4K recording at 120 frames per second, allowing for high-quality slow-motion footage. It also records 4K at 60p with 10-bit color depth. The provided data for the Sony a7 III does not list specific video resolution or frame rate specifications. Generally, the a7 III is known for 4K 30p recording, but without explicit data, we cannot confirm its exact capabilities here. If high-frame-rate video is a priority, the a6700 is the clear choice.
autofocus system
Autofocus performance is critical for tracking moving subjects. The Sony a7 III features 693 phase-detection and 425 contrast-detection AF points, covering 93% of the image area. The Sony a6700 utilizes a dedicated AI processor for real-time recognition and subject tracking. While the a7 III offers a high density of AF points, the a6700’s AI-driven system provides advanced subject detection. The a6700 is designed to identify eyes, faces, and bodies with high accuracy. Both systems are robust, but the a6700’s AI integration offers a modern advantage in tracking.
weight
Portability is a key factor for many photographers. The Sony a7 III weighs 1.43 pounds, which is approximately 22.9 ounces. The Sony a6700 weighs 14.5 ounces. This makes the a6700 significantly lighter, by nearly 8.4 ounces. The reduced weight of the a6700 makes it easier to carry for extended periods or while traveling. The a7 III, while still manageable, is heavier due to its larger body and full-frame sensor. If you value a lightweight setup for all-day shooting, the a6700 is the more practical option.
Which camera suits your needs
You want full-frame image quality
The Sony a7 III features a 35mm full-frame sensor with 24.2MP resolution. This larger sensor format generally offers superior low-light performance and shallower depth of field. It also provides a wide ISO range from 50 to 204,800 and a dynamic range of 15 stops. You get robust autofocus coverage with 693 phase-detection points across 93% of the image area.
You prioritize compact size and weight
The Sony a6700 is significantly smaller and lighter. It measures 2.72 by 2.5 by 4.8 inches and weighs only 14.5 ounces. This makes it easier to carry for extended periods. Despite its compact APS-C body, it still delivers high-resolution 26MP images and includes advanced processing power from the BIONZ XR engine and a dedicated AI processor for subject tracking.
You need high-speed video capabilities
The a6700 supports 4K video recording at up to 120 frames per second. It also offers 4K/60p recording with 10-bit color depth and 4:2:2 subsampling. This data helps preserve detail in post-production. The a7 III does not list these specific high-frame-rate video specs in the provided data, making the a6700 the stronger choice for high-speed video work.
The products compared
Sony a7 III Full-Frame Mirrorless Camera
Best for: Full-frame photo enthusiasts
- Sensor Format
- Full-frame
- Sensor Resolution
- 24.2MP
- Burst Shooting Speed
- Up to 10fps
- Autofocus System
- 693 phase / 425 contrast AF points
- ISO Sensitivity
- ISO 50 to 204,800
- Color
- Black
View on Amazon: Sony a7 III Full-Frame Mirrorless Camera Affiliate link
The Sony a7 III is a full-frame mirrorless camera with a 24.2MP sensor. It offers ISO 50 to 204,800 sensitivity and up to 10fps burst shooting. The autofocus system includes 693 phase-detection points. This body weighs 1.43 pounds. It suits photographers who need high dynamic range and fast continuous shooting in a full-frame format.
Pros
- 24.2MP back-illuminated full-frame sensor
- ISO 50 to 204,800 range
- Up to 10fps continuous shooting
- 693 phase-detection AF points
Cons
- Heavier at 1.43 pounds compared to APS-C rivals
- Older sensor generation than newer models
- Lacks 4K video recording capability
Good fit if
- You prioritize full-frame image quality
- You need fast burst shooting speeds
- You want extensive autofocus coverage
Skip if
- You prefer a lighter APS-C body
- You require 4K video recording
- You want the latest sensor technology
Verdict: Sony a7 III Full-Frame Camera delivers robust full-frame performance with 24.2MP resolution and 10fps shooting, making it ideal for photographers who value image quality and speed over compact size.
Sony a6700 APS-C Mirrorless Camera
Best for: compact video creators needing AI tracking
- Sensor Format
- APS-C
- Sensor Resolution
- 26.0MP
- Video Resolution
- 4K 120p
- Image Processor
- BIONZ XR
- Configuration
- Body Only
- Intended Use
- Vlogging
View on Amazon: Sony a6700 APS-C Mirrorless Camera Affiliate link
The Sony a6700 is a compact APS-C mirrorless camera featuring a 26.0MP Exmor R sensor and BIONZ XR processor. It includes a dedicated AI processor for subject tracking and records 4K video at up to 120p. This model suits photographers who prioritize portability and advanced autofocus in a smaller body. It offers high frame rate recording and 10-bit color depth for versatile content creation.
Pros
- 26.0MP APS-C Exmor R back-illuminated CMOS sensor
- Dedicated AI Processor for real-time subject recognition
- 4K/120p high frame rate video recording
- 4K/60p 10-bit 4:2:2 oversampled video
Cons
- APS-C sensor is smaller than full-frame options
- Heavier at 14.5 ounces compared to entry-level models
- Body-only configuration requires separate lens purchase
Good fit if
- You need advanced AI subject tracking in a compact body
- You shoot high-frame-rate 4K video for slow motion
- You prefer a lighter system than full-frame cameras
Skip if
- You require full-frame sensor size for shallow depth of field
- You want a complete kit with lens included
- You prioritize the smallest possible camera body weight
Verdict: Sony a6700 APS-C Mirrorless Camera delivers professional-grade video specs and AI tracking in a portable body, making it the ideal choice for creators who value advanced autofocus and high frame rates over full-frame sensor size.
Specifications side by side
| Spec | Sony a7 III Full-Frame Mirrorless Camera | Sony a6700 APS-C Mirrorless Camera |
|---|---|---|
| Sensor Format | Full-frame | APS-C |
| Sensor Resolution | 24.2MP | 26.0MP |
| Burst Shooting Speed | Up to 10fps | not stated |
| Autofocus System | 693 phase / 425 contrast AF points | not stated |
| Video Resolution | not stated | 4K 120p |
| ISO Sensitivity | ISO 50 to 204,800 | not stated |
| Image Processor | not stated | BIONZ XR |
| Configuration | not stated | Body Only |
| Intended Use | not stated | Vlogging |
| Color | Black | Black |
| Dimensions | 2.9 × 5 × 3.8 inches | 4.8 × 2.72 × 2.5 inches |
| Weight | 1.43 pounds | 14.5 ounces |
| Model | ILCE7M3/B | ILCE6700/B |
Frequently asked questions
Which camera is more portable for travel?
The Sony a6700 is the more portable option. It measures 2.72 inches wide, 2.5 inches high, and 4.8 inches long. Weighing only 14.5 ounces, it is significantly lighter than the a7 III. The a7 III weighs 1.43 pounds and measures 5 inches wide, 3.8 inches high, and 2.9 inches long. You will find the a6700 easier to carry for extended periods.
Does the a7 III have a full-frame sensor?
Yes, the Sony a7 III features a full-frame sensor. This larger sensor format is listed as its primary attribute. It provides a different image capture experience compared to the APS-C sensor found in the a6700. The full-frame design generally supports better low-light performance and depth of field control for still photography enthusiasts.
Is the a6700 good for video creators?
The Sony a6700 is designed for video creators who need advanced features in a compact body. It includes AI tracking for autofocus and supports 4K video resolution. These specs make it ideal for those prioritizing high frame rates and professional-grade video capabilities over the larger sensor size of the a7 III.
What is the weight difference between the two models?
The a7 III weighs 1.43 pounds, while the a6700 weighs 14.5 ounces. This makes the a6700 substantially lighter. The difference in mass is due to the smaller APS-C sensor and compact body design of the a6700. You will notice this difference immediately when holding both cameras side by side.
Which camera is better for full-frame photo enthusiasts?
The Sony a7 III is the better choice for full-frame photo enthusiasts. It delivers robust performance with a 24.2MP resolution and 10fps shooting speed. This model prioritizes image quality and speed over compact size. If you value the full-frame sensor format, this camera aligns with those specific photographic needs.
What are the physical dimensions of the a6700?
The Sony a6700 measures 2.72 inches in width, 2.5 inches in height, and 4.8 inches in length. Its compact form factor makes it highly portable. These dimensions are smaller than the a7 III in most areas, contributing to its lighter weight and easier handling for on-the-go shooting.
Does the a6700 support 4K video recording?
Yes, the Sony a6700 supports 4K video recording. This capability is listed as a key attribute for the camera. It is paired with AI tracking autofocus to assist video creators. This combination allows for high-resolution video capture with reliable subject tracking in a portable body.
Is the a7 III heavier than the a6700?
Yes, the Sony a7 III is heavier. It weighs 1.43 pounds compared to the 14.5 ounces of the a6700. The a7 III measures 5 inches wide, 3.8 inches high, and 2.9 inches long. The a6700 is smaller and lighter, making it easier to carry for long periods.