• 1/2.35 inch 27.3mm2
  • 8.0 megapixels
  • 36.00mm - 180.00mm (35mm eq.)
  • 1/3 inch 17.3mm2
  • 10.1 megapixels
  • 29.00mm - 87.00mm (35mm eq.)
  • Detailed specifications
  • Pentax Optio M50
  • Nikon Coolpix S31
Links
Prices:    
Manufacturer URL: Manufacturer website Manufacturer website
Predecessor:    
Successor:    
General
Model Number: M50 S31
Alternate Model Number(s):    
Camera Format: Ultra Compact Compact
Currently Manufactured: No No
Retail Price: $229.95 $119.95
Street Price: $139.95 $89.00
Date Available: 2008-03-30 2013-02-15
Tripod Mount: Yes Yes
Weight: 4.1 oz (116 g) 6.5 oz (185 g)
includes batteries
Size: 3.7 x 2.2 x 0.9 in.
(94 x 56 x 23 mm) 		4.1 x 2.6 x 1.6 in.
(105 x 65 x 42 mm)
Waterproof: No Yes
Waterproof Depth: n/a  
Image Sensor
Sensor Type: CCD CCD
Sensor Manufacturer:    
Effective Megapixels: 8.0 10.1
Sensor Format: 1/2.35 inch 1/3 inch
Sensor size: 27.2556mm2 (6.03mm x 4.52mm) 17.28mm2 (4.8mm x 3.6mm)
Approximate Pixel Pitch: 1.85 microns 1.32 microns
Focal Length Multiplier: n/a n/a
Aspect Ratio: 4:3 4:3
Color Filter Type:    
Anti Aliasing Filter:    
Self-Cleaning: No No
Sensor shift image stabilization: No No
On-Sensor Phase Detect: No No
DxO Sensor Score:    
DxO Color Depth Score (bits):    
DxO Dynamic Range Score (evs):    
DxO Maximum Effective ISO Score (iso):    
Image Capture
Image Resolution: 3264 x 2448 (8.0 MP, 4:3),
2592 x 1944 (5.0 MP, 4:3),
2304 x 1728 (4.0 MP, 4:3),
2048 x 1536 (3.1 MP, 4:3),
1600 x 1200 (1.9 MP, 4:3),
1024 x 768 (0.8 MP, 4:3),
640 x 480 (0.3 MP, 4:3) 		3648 x 2736 (10.0 MP, 4:3),
2272 x 1704 (3.9 MP, 4:3),
1600 x 1200 (1.9 MP, 4:3)
Image File Format: JPEG (EXIF 2.2) JPEG
Continuous-mode frames/second: n/a 1.5
Video Capture
Can take movies: Yes Yes
Movie Resolution: 640x480 (30/​15)
320x240 (30/​15) 		1280x720 (30p)
Movie File Format: AVI (MotionJPEG)  
Composite Video Out: Yes Yes
NTSC/PAL Switchable Video: Yes Yes
Video Usable as Viewfinder:
HD Video Out:
HD Video Connection:
Lens & Optics
Lens Mount: n/a n/a
Lens: Pentax zoom lens, 8 elements, 6 groups (4 aspherical elements) NIKKOR; 6 elements in 5 groups
Focal Length (35mm equivalent): 36 - 180mm 29 - 87mm
Focal Length (actual): 6.3 - 31.5mm 4.1 - 12.3mm
Zoom Ratio: 5.00x 3.00x
Aperture Range: f/3.5 (wide) / f/5.6 (tele) - ??? f/3.3 (wide) / f/5.9 (tele) - ???
Integrated ND Filter: No No
Normal Focus Range: 40 cm to Infinity
15.7 in to Infinity 		30 cm to Infinity
11.8 in to Infinity
Macro Focus Range: 10 - 100 cm
3.9 - 39.4 in 		5 cm to Infinity
2.0 in to Infinity
Filter Thread: n/a n/a
Thread Type: n/a n/a
Optical Image Stabilization: No No
Digital Zoom: Yes Yes
Digital Zoom Values: Up to 5.1x Up to 4x
Auto Focus
Auto Focus: Yes Yes
Auto Focus Type: 9-point TTL contrast detection Contrast Detection: Center, Face detection
Auto Focus Assist Light? No Yes
Manual Focus: Yes No
Viewfinder
Viewfinder: LCD LCD
Viewfinder Type:    
Focus Peaking: No No
EVF Resolution: n/a n/a
Viewfinder Magnification (35mm equivalent):    
Viewfinder Magnification (nominal/claimed):    
Display
Eye-level Viewfinder: No No
Rear Display: Yes Yes
Rear Display Size (inches): 2.5 2.7
Rear Display Resolution: 230,000 dots 230,000 dots
Touchscreen: No No
Articulating Screen: No No
Tilt Swivel Screen: No No
Selfie Screen: No No
Max Playback Zoom: 8.0x  
Top Deck Display:
Exposure
Maximum ISO (native):    
Minimum ISO (native):    
ISO Settings: Auto (64 - 3200); 6400 only available in Digital SR mode Auto, 80, 100, 200, 400, 800, 1600
Auto ISO Mode: No Yes
White Balance Settings: Auto, daylight, shade, tungsten, fluorescent, custom Auto
Shutter Speed Range: 1/2000 - 4 sec 1/2000 - 4 sec
Bulb Mode: No No
Exposure Compensation: +/- 2.0EV in 0.3EV steps +/- 2.0EV in 0.3EV steps
Metering Modes: TTL multi-segment, Center-weighted, Spot Matrix, Center-weighted (digital zoom less than 2x), Spot (digital zoom 2X or more)
Program Auto Exposure: Yes Yes
Aperture Priority: No No
Shutter Priority: No No
Full Manual Exposure: No No
Creative Exposure Modes: Night Scene, Landscape, Flower, Natural Skin Tone, Portrait, Surf & Snow, Sport, Digital SR (5M), Kids, Pet, Food, Panorama, Digital Wide Angle (5M) Close Up, Continuous shooting, Diorama effect, Fireworks Show, Food, Interval shooting, Mirror, Underwater, Soft
Self Timer: 2 or 10 seconds 10, smile seconds
Time Lapse (intervalometer):    
High Resolution Composite: No No
Flash
Built-in Flash: Yes Yes
Flash Modes: Auto flash, flash on, flash off, red-eye reduction Auto, Auto w/ Red-eye Reduction, Flash Off, Flash On, w/ Red-eye Reduction, Flash Off
Flash Guide Number (ISO 100): n/a n/a
Flash Range Description: 14’ (wide, auto ISO), 9.2’ (tele, auto ISO) Auto ISO: [W]: 0.5 to 3.5m (1ft. 8 in. to 11 ft.) [T]: 0.5 to 2.0m (1ft 8 in. to 6 ft 6 in.)
Max Flash Sync:    
Flash Exposure Compensation:    
External Flash Connection: n/a n/a
Built-In Wireless Flash Control:    
Image Storage
Usable Memory Types: SD / SDHC SD / SDHC / SDXC
UHS Support:    
Other Memory:    
Dual Card Slots: No No
RAW Capture Support: No No
Uncompressed Format:    
Movie File Format: AVI (MotionJPEG)  
Included Memory: 51.1 MB 25.0 MB
Included Memory Type: Internal Internal
Connectivity
Built-In Wi-Fi: No No
NFC: No
Bluetooth: No No
Built-In GPS: No No
Microphone Jack: No 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: No
Remote Control Type:    
Connections (extended): DC Input  
Performance Timing
Cycle time for JPEG shooting in single shot mode (seconds per frame, max resolution):    
Cycle time for RAW shooting in single shot mode (seconds per frame):    
Buffer size for RAW shooting in single shot mode (frames):    
Cycle time for RAW+JPEG shooting in single shot mode (seconds per shot):    
Camera penalizes early shutter press?
JPEG shooting speed in burst mode (fps, max resolution):   1.5
Buffer size for JPEG shooting in burst mode (frames, max resolution):   4
RAW shooting speed in burst mode (fps):    
Buffer size for RAW shooting in burst mode (frames):    
RAW+JPEG shooting speed in burst mode (fps):    
Buffer Size for RAW+JPEG shooting in burst mode (frames):    
Shutter lag (full AF, wide/mid):    
Shutter lag (full AF, tele):    
Shutter lag (full AF, live view - DSLR):    
Shutter lag (prefocused, live view - DSLR):    
Shutter Lag (manual focus):    
Shutter lag (full AF, with flash):    
Shutter Lag (prefocused):    
Shutter Lag (notes):    
Startup Time:    
Play -> Record Time:    
Flash cycle time, full power:    
Power
Battery Life, Stills (CIPA Rating Monitor/Live View): 210 shots 260 shots
Battery Life, Still (CIPA Rating OVF/EVF):    
Battery Life, Video:    
Battery Form Factor: Proprietary D-LI78 Proprietary EN-EL12
Usable Battery Types: Lithium-ion rechargeable Lithium-ion rechargeable
Batteries Included: 1 x Proprietary D-LI78 Lithium-ion rechargeable 1 x Proprietary EN-EL12 Lithium-ion rechargeable
Battery Charger Included (dedicated charger or AC/USB adapter): Yes Yes
Dedicated Battery Charger Included:
Internal Charging Supported:
Software
Included Software: TBA Nikon ViewNX 2 CD-ROM
OS Compatibility: TBA Windows, Mac OS
Miscellaneous
Notes & Features: Waterproof (up to 16.4 feet), Shockproof (up to 3.9 feet) and Dustproof. Available in White, Blue, Pink, Brown or Yellow.