The Pentax Optio S45 and S55 feature a Pentax SMC 3x optical zoom lens, a 4 megapixel sensor in the S45, and a 5 megapixel sensor in the S55, and a large 2.5" screen, all encased in a small aluminium body.  The camera's 3x optical zoom lens is equivalent to 35.6 – 107mm on a 35mm camera. It records unlimited 320 x 240 / 30fps videos with sound. The camera's very compact (on the box it reads 'ultra-compact', and it will easily fit into trouser pockets), takes AA batteries and measures: 89 x 58.5 x 27.5mm - only slightly larger than the Canon Digital IXUS 700, and weighs 135g.

Specifications

 More information :  Announced 11-May-05
 Max resolution   :   2304 x 1728
 Low resolution   :   1600 x 1200, 1024 x 768, 640 x 480
 Image ratio w:h  :    4:3
 Effective pixels   :   4.0 million
 Sensor photo detectors   :   4.2 million
 Sensor size   :   1/2.5 "
 Sensor type :     CCD
 Colour filter array   :   RGB
 Sensor manufacturer    :  Unknown
 ISO rating  :    Auto, 100, 200, 400
 Zoom wide (W)   :   35.6 mm
 Zoom tele (T)  :    107 mm (3 x)
 Digital zoom  :    Yes, 2.6x
 Image stabilization  :    No
 Auto Focus   :   Yes
 Manual Focus   :   Yes
 Auto focus type   :   TTL
 Normal focus range  :    40 cm
 Macro focus range   :   6 cm
 White balance override   :   5 positions, plus manual one-touch
 Aperture range   :   F2.6 - F4.8 / ??
 Min shutter   :   4 sec
 Max shutter   :   1/2000 sec
 Built-in Flash   :   Yes
 Flash guide no.  :    4.9 m (16 ft) 9 m
 External flash   :   No
 Flash modes  :    Auto, On, Off, Red-eye reduction
 Exposure compensation  :    -2 EV to +2 EV in 1/3 EV steps
 Metering  :    Multi-segment, Center weighted, Spot
 Aperture priority  :    No
 Shutter priority  :   No
 Focal length multiplier       
 Lens thread  :    No
 Continuous Drive   :   Yes
 Movie Clips  :    Yes, 320 x 240, 15/30 fps
 Remote control   :   Optional
 Tripod mount   :   Yes
 Self-timer   :   Yes
 Timelapse recording   :   No
 Orientation sensor   :   No
 Storage types  :   SD/MMC card + Internal
 Storage included   :   11 MB Internal
 Uncompressed format   :   No
 Compressed format   :   JPEG (EXIF 2.2)
 Quality Levels  :    Normal, Fine, Superfine
 Viewfinder   :   No
 LCD   :   2.5 "
 LCD Pixels   :   115,000
 Video out   :   Yes
 USB  :    Yes
 Firewire (IEEE 1394) :     No
 Battery / Charger   :   Yes
 Battery   :   AA (2) batteries (NiMH recommended)
 Weight (inc. batteries)   :   155 g (5.5 oz)
 Dimensions   :   89 x 59 x 28 mm (3.5 x 2.3 x 1.1 in)

Review

The Pentax Optio S45 produces decent snaps, but its sluggish performance puts a damper on an otherwise useful little camera.
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