• APS-C 369.7mm2
  • 24.3 megapixels
  • ISO 100 - 16,000
  • APS-C 366.6mm2
  • 20.1 megapixels
  • ISO 100 - 51,200
  • Detailed specifications
  • Sony Alpha SLT-A77
  • Pentax K-S1
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Manufacturer URL: Manufacturer website Manufacturer website
Predecessor:    
Successor: Sony A77 II
A77 vs A77 II
 
General
Model Number: A77 K-S1
Alternate Model Number(s):    
Camera Format: SLR SLR
Currently Manufactured: No No
Retail Price: $1999.99 $799.95
Street Price: $1,899.00 $501.65
Date Available: 2011-10-15 2014-09-15
Tripod Mount: Yes Yes
Weight: 48.1 oz (1,363 g)
includes batteries, kit lens
27.0 oz (765 g)
includes batteries, kit lens
Size: 5.6 x 4.1 x 3.2 in.
(143 x 104 x 81 mm)
4.8 x 3.7 x 2.8 in.
(121 x 93 x 70 mm)
Waterproof: No No
Waterproof Depth: n/a n/a
Image Sensor
Sensor Type: CMOS CMOS
Sensor Manufacturer: Sony  
Effective Megapixels: 24.3 20.1
Sensor Format: APS-C APS-C
Sensor size: 369.72mm2 (23.7mm x 15.6mm) 366.6mm2 (23.50mm x 15.60mm)
Approximate Pixel Pitch: 3.95 microns 4.29 microns
Focal Length Multiplier: 1.5x 1.5x
Aspect Ratio: 3:2 3:2
Color Filter Type: RGBG RGBG
Anti Aliasing Filter: Fixed Optional
Self-Cleaning: Yes Yes
Sensor shift image stabilization: Yes Yes
On-Sensor Phase Detect: No No
DxO Sensor Score: 78 78
DxO Color Depth Score (bits): 24.0 23.5
DxO Dynamic Range Score (evs): 13.2 13.0
DxO Maximum Effective ISO Score (iso): 801 1,061
Image Capture
Image Resolution: 6000 x 4000 (24.0 MP, 3:2),
6000 x 3376 (20.3 MP, 16:9),
4240 x 2832 (12.0 MP, 3:2),
4240 x 2400 (10.2 MP, Other),
3008 x 2000 (6.0 MP, 3:2),
3008 x 1688 (5.1 MP, 16:9),
12416 x 1856 (23.0 MP, Other),
8192 x 1856 (15.2 MP, Other),
2160 x 5536 (12.0 MP, Other),
2160 x 3872 (8.4 MP, Other),
7152 x 1080 (7.7 MP, Other),
4912 x 1080 (5.3 MP, Other),
1920 x 1080 (2.1 MP, 16:9)
5472 x 3648 (20.0 MP, 3:2),
4224 x 2816 (11.9 MP, 3:2),
3072 x 2048 (6.3 MP, 3:2),
1920 x 1280 (2.5 MP, 3:2)
Image File Format: JPEG (EXIF 2.3), MPO (3D), 12-bit RAW (ARW 2.3), RAW+JPEG JPEG (EXIF 2.30), 12-bit RAW (.PEF, .DNG)
Continuous-mode frames/second: 11.6 5.4
Video Capture
Can take movies: Yes Yes
Movie Resolution: 1920x1080 (60p/​28Mbps/​PS or 60i/​24Mbps/​FX or 60i/​17Mbps/​FH or 24p/​24Mbps/​FX or 24p/​17Mbps/​FH)
1440x1080 (30p/​12Mbps)
640x480 (30p/​3Mbps)
1920x1080 (30p/​25p/​24p)
1280x720 (60p/​50p)
Movie File Format: AVCHD 2.0 / MP4; Audio :Dolby Digital (AC-3) / MPEG-4 AAC-LC, stereo MPEG-4 AVC/H.264 (MOV)
Composite Video Out: No
NTSC/PAL Switchable Video: n/a n/a
Video Usable as Viewfinder: n/a n/a
HD Video Out: Yes Yes
HD Video Connection: HDMI HDMI
Lens & Optics
Lens Mount: Sony Alpha (Minolta A) Pentax K (KA/KAF/KAF2)
Lens: Sony 16-50mm f/2.8 DT SSM (SAL1650) smc Pentax-DA L 18-55mm f/3.5-5.6 AL
Focal Length (35mm equivalent): 24 - 75mm 27 - 83mm
Focal Length (actual): 16 - 50mm 18 - 55mm
Zoom Ratio: 3.13x 3.06x
Aperture Range: f/2.8 - f/22 (W/T) f/3.5 - f/22 (wide) / f/5.6 - f/40 (tele)
Integrated ND Filter: No No
Normal Focus Range: 30 cm to Infinity
11.8 in to Infinity
25 cm to Infinity
9.8 in to Infinity
Macro Focus Range:    
Filter Thread: n/a 52.0mm
Thread Type: n/a n/a
Optical Image Stabilization: No No
Digital Zoom: Yes
Digital Zoom Values: 1.4x / 2x  
Auto Focus
Auto Focus: Yes Yes
Auto Focus Type: Phase Detection: 19 points (11 points cross type); Wide (auto, 19 points), Zone, Spot, Local SAFOX IX i+, TTL phase-matching -11 point (9 cross type focus points in the center)
Auto Focus Assist Light? Yes Yes
Manual Focus: Yes Yes
Viewfinder
Viewfinder: EVF / LCD Optical / LCD
Viewfinder Type: EVF type; 1.3cm (0.5") 2,359K-dot OLED, 100% coverage, 1.09x mag., 22mm eyepoint, -4 to +3 diopter SLR type; eye-level pentaprism, ~100% coverage, 0.95x mag., 20.5mm eyepoint, -2.5 to +1.5 diopter
Focus Peaking: Yes Yes
EVF Resolution: 2,359,000 dots n/a
Viewfinder Magnification (35mm equivalent): 0.73x 0.63x
Viewfinder Magnification (nominal/claimed): 1.09x 0.95x
Display
Eye-level Viewfinder: Yes Yes
Rear Display: Yes Yes
Rear Display Size (inches): 3.0 3.0
Rear Display Resolution: 921,600 dots (307,200 px) 921,600 dots (307,200 px)
Touchscreen: No No
Articulating Screen: Yes No
Tilt Swivel Screen: Yes No
Selfie Screen: Yes No
Max Playback Zoom: 13.6x 16.0x
Top Deck Display: Yes No
Exposure
Maximum ISO (native): 16000 51200
Minimum ISO (native): 100 100
ISO Settings: Auto (100-12800 with selectable limits), 50 (expanded), 100, 200, 400, 800, 1600, 3200, 6400, 12800, 16000. (Multi-frame NR mode up to ISO 25600) Auto, 100-51200 (1, 1/2 or 1/3 EV steps)
Auto ISO Mode: Yes Yes
White Balance Settings: Auto WB, Daylight, Shade, Cloudy, Incandescent, Fluorescent (Warm white/Cool white/Day white/Daylight), Flash, C. Temp 2500 to 9900K, C Filter G7 to M7 (15-step), Custom, AWB micro adjustment Auto, Multi Auto, Daylight, Shade, Cloudy, Fluorescent Light (D: Daylight Color, N: Daylight White, W: Cool White, L: Warm White), Tungsten Light, Flash, CTE, Manual, Color Temperature
Shutter Speed Range: 1/8000 - 30 sec 1/6000 - 30 sec
Bulb Mode: Yes Yes
Exposure Compensation: +/- 5.0EV in 0.3EV steps +/- 5.0EV in 0.3EV steps
Metering Modes: 1200-zone Evaluative, Center-weighted, Spot TTL open-aperture: 77 segment Multi, Center-weighted, Spot
Program Auto Exposure: Yes Yes
Aperture Priority: Yes Yes
Shutter Priority: Yes Yes
Full Manual Exposure: Yes Yes
Creative Exposure Modes: Scene Modes: Portrait, Landscape, Macro, Sports Action, Sunset, Night Portrait, Night Scene, Hand-held Twilight, Auto HDR, Sweep Panorama (2D/3D) Sensitivity Priority, Shutter & Aperture Priority (Tav); Scene: Portrait, Landscape, Macro, Moving Object, Night Scene Portrait, Sunset, Blue Sky, Forest, Night Scene, Night Scene HDR (JPEG only), Night Snap, Food, Pet, Kids, Surf & Snow, Backlight Silhouette, Candlelight, Stage Lighting, Museum; Effect: Faded Color, Clear Tone, Brilliant Color, Unicolor Bold, Vintage Color, Cross Processing, Warm Fade, Tone Expansion, Bold Monochrome, Infrared Filter, Vibrant Color Enhance; Digital filters (capture): Extract Color, Replace Color, Toy Camera, Retro, High Contrast, Shading, Invert Color, Unicolor Bold, Bold Monochrome; HDR: Auto, HDR1, HDR2, HDR3
Self Timer: 2, 10; 3 or 5 frames after 10 seconds 2 or 12 seconds
Time Lapse (intervalometer):    
High Resolution Composite: No No
Flash
Built-in Flash: Yes Yes
Flash Modes: Auto, Off, Fill-flash, Rear sync, Wireless, High-Speed sync (with external flash), Slow sync, Red-eye reduction: On/Off Auto Flash Discharge, Auto Flash + Red-eye Reduction (Auto Picture, Scene) Flash On, Flash On+ Red-eye Reduction, Slow-speed Sync, Trailing Curtain Sync, Manual Flash Discharge (Full-1/128)
Flash Guide Number (ISO 100): 12.0 m / 39.4 ft. 10.0 m / 32.8 ft.
Flash Range Description: GN=12(m) at ISO 100; Range is lens aperture dependent Depends on lens
Max Flash Sync: 1/250 1/180
Flash Exposure Compensation: +/- 2.0 EV in 0.3EV steps -2 to +1 EV in 0.5EV steps
External Flash Connection: Proprietary Hot Shoe, PC Sync Terminal Hot Shoe
Built-In Wireless Flash Control: Full TTL exposure  
Image Storage
Usable Memory Types: MS Duo / MS PRO Duo / SD / SDHC / SDXC SD / SDHC / SDXC
UHS Support: UHS-I UHS-I
Other Memory:   UHS-I compliant
Dual Card Slots: No No
RAW Capture Support: Yes Yes
Uncompressed Format: 12-bit RAW (ARW 2.3), RAW+JPEG 12-bit RAW (.PEF, .DNG)
Movie File Format: AVCHD 2.0 / MP4; Audio :Dolby Digital (AC-3) / MPEG-4 AAC-LC, stereo MPEG-4 AVC/H.264 (MOV)
Included Memory: No memory included No memory included
Included Memory Type:    
Connectivity
Built-In Wi-Fi: No No
NFC: No No
Bluetooth: No No
Built-In GPS: Yes No
Microphone Jack: Yes No
Headphone Jack: No No
External Connections: USB 2.0 High Speed USB 2.0 High Speed
PictBridge Compliant: Yes No
DPOF Compliant: Yes Yes
Remote Control: Yes Yes
Remote Control Type: Optional Wireless or Wired Optional IR
Connections (extended): Type-C HDMI Mini Connector (BRAVIA Sync, PhotoTV HD); Wired Remote Terminal, External Stereo Micophone Jack, DC Input Micro (Type D) HMDI
Performance Timing
Cycle time for JPEG shooting in single shot mode (seconds per frame, max resolution): 0.42  
Cycle time for RAW shooting in single shot mode (seconds per frame): 0.42  
Buffer size for RAW shooting in single shot mode (frames): 5  
Cycle time for RAW+JPEG shooting in single shot mode (seconds per shot): 0.42  
Camera penalizes early shutter press? No
JPEG shooting speed in burst mode (fps, max resolution): 11.6 5.4
Buffer size for JPEG shooting in burst mode (frames, max resolution): 17 20
RAW shooting speed in burst mode (fps): 11.6  
Buffer size for RAW shooting in burst mode (frames): 14  
RAW+JPEG shooting speed in burst mode (fps): 11.6  
Buffer Size for RAW+JPEG shooting in burst mode (frames): 13  
Shutter lag (full AF, wide/mid): 0.12 seconds  
Shutter lag (full AF, tele):    
Shutter lag (full AF, live view - DSLR):    
Shutter lag (prefocused, live view - DSLR):    
Shutter Lag (manual focus): 0.085 seconds  
Shutter lag (full AF, with flash): 0.33 seconds  
Shutter Lag (prefocused): 0.054 seconds  
Shutter Lag (notes): Full AF, Wide-area mode = 0.119s  
Startup Time: 0.8 seconds  
Play -> Record Time: 1.0 seconds  
Flash cycle time, full power: 3.2 seconds  
Power
Battery Life, Stills (CIPA Rating Monitor/Live View): 530 shots  
Battery Life, Still (CIPA Rating OVF/EVF): 470 shots 480 shots
Battery Life, Video:    
Battery Form Factor: Proprietary NP-FM500H Proprietary D-LI109
Usable Battery Types: Lithium-ion rechargeable Lithium-ion rechargeable
Batteries Included: 1 x Proprietary NP-FM500H Lithium-ion rechargeable 1 x Proprietary D-LI109 Lithium-ion rechargeable
Battery Charger Included (dedicated charger or AC/USB adapter): Yes Yes
Dedicated Battery Charger Included: Yes
Internal Charging Supported: No
Software
Included Software: Software CD-ROM (includes Picture Motion Browser, Image Data Converter 4) Digital Camera Utility 5 Software CD-ROM
OS Compatibility: Windows XP SP3/Vista SP2/7, Mac OS X (v.10.5 +); PMB is Windows only  
Miscellaneous
Notes & Features: SteadyShot INSIDE Image Stabilization, Articulating LCD, 1080p HD Video, Auto+, Multi-frame NR, Hand-held Twilight, Auto HDR, Picture Effect, D-Range Optimizer, 2D/3D Sweep Panorama, Smile Shutter, DOF Preview, 12fps Burst Mode, Built-in GPS. The K-S1 comes in 3 standard colors: black, blue, and white. In addition, two separate color collections are available; The Fabric Collection, containing 4 unique colors such as cotton beige and tweed gray – and the Night Sky Collection, with 5 more elegant colors like Sunset Orange, Dawn Purple, and Midnight Black.