Sony Alpha 7R IIIA vs Pentax K-3 Mark II

General	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Brand	Sony	Pentax
Model	Alpha 7R IIIA	K-3 Mark II
Predecessor Model	Sony Alpha 7R II	Pentax K-3
Successor Model	Sony Alpha 7R IV	Pentax K-3 Mark III
MSRP	$3199 (body only)	$1099/£769 (body only)
Camera Type	Interchangeable Lens	Interchangeable Lens
Body Type	Mirrorless	DSLR
Video Capture

Sensor	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Sensor Type	BSI-CMOS	CMOS
Sensor Size	Full Frame	APS-C
Sensor Dimensions	35.9 x 24 mm	23.5 x 15.6 mm
Total Pixels	43.6 Megapixel	24.71 Megapixel
Effective Pixels	42.4 Megapixel	24.35 Megapixel
Low Pass Filter
Native ISO Range	100 - 32,000	100 - 51,200
Boosted ISO Range	50 - 102,400
Sensor Shift High Resolution Mode

Photo	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Processor	BIONZ X	PRIME III
Max Image Resolution	7952 x 5304	6016 x 4000
Other Resolutions		4608 x 3072, 3072 x 2048, 1920 x 1080
Image Aspect Ratios	3:2, 16:9	3:2
Image File Format	JPEG, RAW
JPEG Quality Levels	Extra fine, fine, standard	Best, better, good
Bit Depth	14-Bit	14-Bit
Color Space		sRGB, Adobe RGB
Timelapse Recording
White Balance	Presets: Auto, Cloudy, Color Temperature, Custom, Daylight, Flash, Fluorescent (Cool White), Fluorescent (Daylight), Fluorescent (Warm White), Incandescent, Shade, Underwater

Focus	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Focusing System	Fast Hybrid AF (Phase-detection / Contrast-detection)
Autofocus Modes	Multi-area Center Selective single-point Tracking Single Continuous Touch Face Detection Live View	Multi-area Center Selective single-point Tracking Single Continuous Face Detection Live View
Lens Servo	Automatic, Continuous-Servo AF, Direct Manual Focus, Manual Focus, Single-Servo AF	Continuous-Servo AF, Manual Focus, Single-Servo AF
AF Detection Range	-2 to +20 EV
Number of Focus Points	425	27
Number of Cross-type Focus Points		25
Touch-to-Focus
Live View Autofocus
Animal Eye Detection
Vehicle Tracking Mode
Insect Tracking Mode
Contrast Detection for Autofocus
Phase Detection for Autofocus
Focusing Screen		Natural-Bright-Matte III focusing screen

Optics	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Lens Mount	Sony E	Pentax KAF2
Crop Factor	1x	1.5x
Image Stabilization	5-Axis Sensor Shift	Sensor Shift
Image Stabilization Compensation	5.5 stops	4.5 stops
Digital Image Stabilization

Screen	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Screen Type	Tilting	Fixed
Screen Technology	TFT LCD	TFT LCD
Touch Screen
Screen Size	3.0"	3.2"
Screen Resolution	2,360k dot	1,037k dot
Top LCD Screen
Live View
Live Composition

Viewfinder	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Viewfinder	Electronic	Optical (pentaprism)
Viewfinder Size	0.5"
Viewfinder Coverage	100%	100%
Viewfinder Magnification	0.78x	0.95x
Viewfinder Magnification (35mm equivalent)	0.78x	0.63x
Viewfinder Resolution	3,686k dot
Viewfinder Eyepoint	23 mm
Diopter Adjustment	-4 to +3	-2.5 to +1.5

Shutter	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Shutter Type	Electronic
Min Shutter Speed	30 sec	30 sec
Max Shutter Speed (Mechanical or 1st Curtain)	1/8000 sec	1/8000 sec
Max Continuous Shooting	10.0 fps	8.3 fps
Continuous Shooting Resolution/fps/buffer	Up to 10 fps at 42.4 MP for up to 76 Frames (Raw) / 76 Frames (JPEG) Up to 8 fps at 42.4 MP for up to 76 Frames (Raw) / 76 Frames (JPEG) Up to 6 fps at 42.4 MP for up to 76 Frames (Raw) / 76 Frames (JPEG) Up to 3 fps at 42.4 MP for up to 76 Frames (Raw) / 76 Frames (JPEG)	Max. approx. 12 fps, JPEG ( L: at Continuous H): up to approx. 37 frames, RAW: up to approx. 32 frames, RAW+: up to approx. 30 frames Max. approx. 7.0 fps, JPEG (L: at Continuous M): up to approx. 60 frames, RAW: up to approx. 37 frames, RAW+: up to approx. 33 frames Max. approx. 2.5 fps, JPEG ( L: at Continuous L): up to approx. 90 frames, RAW: up to approx. 39 frames, RAW+: up to approx. 37 frames

Flash	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Built-in Flash
Flash Modes	Off Auto Fill-flash Slow Sync Rear Sync Red-eye reduction Wireless Hi-speed sync	Auto Flash Discharge Auto Flash + Red-eye Reduction Flash On Flash On + Red-eye Reduction Slow-speed Sync Slow-speed Sync + Red-eye P-TTL Trailing Curtain Sync Contrast-control-sync High-speed sync Wireless sync (available with dedicated external flash)
Max Flash Sync Speed	1/250 sec	1/180 sec
Flash Compensation	-3 to +3 EV (1/3, 1/2 EV Steps)
External Flash Connectivity
External Flash System	TTL
External Flash Connection	Intelligent Hot Shoe, PC Terminal	Hot Shoe, PC Terminal

Exposure	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Exposure Metering Modes	Multi Center-weighted Spot	Multi Center-weighted Spot
Exposure Modes	Aperture Priority, Auto, Manual, Program, Shutter Priority
Metering Range	-3 to +20 EV	-3 to +20 EV
Exposure Compensation	±5 EV (1/3 EV, 1/2 EV increments)	±5 EV (1/3 EV, 1/2 EV increments)
Exposure Bracketing	±5 EV (3, 5 shots at 1/3 EV, 1/2 EV, 2/3 EV, 1 EV, 2 EV increments)	±2 EV (2, 3, 5 shots at 1/3 EV, 1/2 EV increments)
Exposure Lock		Button type (timer type: two times the meter operating time set in Custom Setting); Continuous as long as the shutter button is halfway pressed

DXO	Sony Alpha 7R IIIA	Pentax K-3 Mark II
DxO Low Light ISO	3523	1106
DxO Color Depth	26.0	23.6
DxO Dynamic Range	14.7	13.6
DxO Overall Score	100	80

Video	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Internal Recording Modes	XAVC S 4K UHD: 3840 x 2160 @ 23.98/25/29.97 fps [60 to 100 Mbps] Full HD: 1920 x 1080p @ 23.98/25/29.97/50/59.94/100 fps [100 Mbps] HD: 1280 x 720 @ 100 fps [50 Mbps] AVCHD Full HD: 1920 x 1080p @ 23.98/25/50/59.94 fps [17 to 28 Mbps] Full HD: 1920 x 1080i @ 50/59.94 fps [17 to 24 Mbps] MP4 Full HD: 1920 x 1080p @ 25/29.97/50/59.94 fps [16 to 28 Mbps] HD: 1280 x 720 @ 25/29.97 fps [6 Mbps]
Video Formats	MPEG-4, AVCHD, XAVC S	MPEG-4, H.264
Max Video Resolution	3840 x 2160	1920 x 1080
External Recording Modes	4:2:2 8-Bit via HDMI UHD 4K (3840 x 2160) @ 23.98/24.00/25/29.97 fps 1920 x 1080p @ 23.98/24.00/50/59.94 fps 1920 x 1080i @ 50/59.94 fps
Webcam Functionality
Gamma Curve	HDR-HLG, Sony S-Log 2, Sony S-Log 3
Unlimited Video Recording
Recording Limit	30 min	25 min

Terminals	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Audio I/O	1 x 1/8" / 3.5 mm TRS Stereo Headphone Output 1 x 1/8" / 3.5 mm TRS Stereo Microphone Input
Power I/O	1 x USB-C Input/Output
Other I/O	1 x Sony Multi/Micro-USB Input/Output (Shared with Remote Input) 1 x USB-C (USB 3.2 / 3.1 Gen 1) Input/Output (Shared with Power Input) 1 x PC Sync Socket Output
USB Speed	USB 3.2 Gen 1x1 (5 GBit/sec)	USB 3.2 Gen 1x1 (5 GBit/sec)
HDMI Output	Micro	Mini
Speaker	Mono	Mono
Built-in Microphone	Stereo	Mono
Microphone Input
Headphone Output
Flash Sync Port

Connectivity	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Built-in GPS
Built-In Wi-Fi		Optional
Wi-Fi Version	802.11b/g/n, 2.4 GHz
Built-In Bluetooth
NFC
Remote Control	wired, wireless, smartphone	optional, wired or wireless

Environmental	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Environmental Sealing
Operating Temperature	32 to 104°F / 0 to 40°C

Physical	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Dimensions	127 x 96 x 74 mm (5 x 3.78 x 2.91")	131 x 100 x 77 mm (5.16 x 3.94 x 3.03")
Weight (inc. batteries)	657 g (1.45 lb / 23.17 oz)	800 g (1.76 lb / 28.22 oz)
Box Dimensions (LxWxH)	9.6 x 6.1 x 5.7"	8.1 x 6.4 x 5.1"
Package Weight	3.005 lb	3.25 lb

Power and Storage	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Battery Pack	NP-FZ100	D-LI90
Battery Life	650 shots	720 shots
USB Charging
Internal Storage
External Storage	Slot 1: SD/SDHC/SDXC (UHS-II) Slot 2: SD/SDHC/SDXC/Memory Stick Duo Hybrid (UHS-I)	Dual Slot: SD/SDHC/SDXC (UHS-I)

Other	Sony Alpha 7R IIIA	Pentax K-3 Mark II
Self Timer	2 or 10 sec; continuous 3 or 5 exposures	2 or 12 seconds
Astro Tracer feature for Astrophotography
Orientation Sensor
Tripod Mounting Thread	1 x 1/4"-20 Female (Bottom)
Accessory Mount	1 x Hot Shoe Mount
Material of Construction	Magnesium Alloy
Electronic Level Gauge

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