Just Announced: The Pentax K-S1 DLSR


Pentax K-S1 DSLR

Expanding its DSLR lineup, Pentax has just announced the new Pentax K-S1. Boasting a compact contemporary design and intuitive user interface, the K-S1 20MP camera offers some of the unique features of its big brother, the Pentax K-3, but adds some refinements on the inside and out.


On the inside, the K-S1 features a new 20MP APS-C CMOS sensor that feeds still image or full 1080p h.264 HD video data through a brand new PRIME M II Image Processing Engine. The sensor helps the K-S1 capture images in very low light, with sensitivity ranging from ISO 100 up to ISO 51200.


The most interesting features might be on the outside of this camera. Beside the bright body colors available for the K-S1, the camera features some eye-catching LED-illuminated buttons and camera controls along with LED indicator lamps in the handgrip that give it a little bit of visual "wow” factor while adding to the functionality of the camera. The shutter release is surrounded by an illuminated ring and the multi-function control wheel and buttons on the rear also glow to assist the shooter in selecting modes and navigating menus.


For shooting, the camera can capture action at 5.4 frames per second at shutter speeds up to 1/6000 of a second. To help keep subjects sharp, the camera features a high-precision SAFOX IXi+ phase-matching autofocus system with 11 detection points, including 9 cross-type points in the center of the frame. The autofocus system sensitivity range is from EV 1 to EV 18 at ISO 100 and the system is assisted, as needed, by an LED autofocus assist lamp. Keeping things steady is an innovative in-body Shake Reduction (SR) mechanism, negating the need for image-stabilized lenses. The camera is compatible with Pentax K-mount lenses.

Sharing a unique-to-Pentax feature with the K-3, the K-S1 also offers the selectable anti-aliasing filter that allows you to toggle the anti-aliasing filter's effect either on or off, providing support for both the high-resolution abilities of a filter-less design as well as advanced moiré protection. Having both options available extends the camera's versatility and allows personalized selection of the benefits best-suited to individual applications.


The K-S1 features a bright 100%-coverage viewfinder with 0.95x magnification and a live-view-capable 921k-dot rear 3.0" LCD that is adjustable in brightness, saturation, and color. The live view can be magnified 2, 4, 8, or 10x and features three different grid options as well as a histogram and bright area warnings. Metering is handled by a 77-segment system with multi-, center-, and spot-metering options, and a built-in retractable flash provides extra light when needed. A built-in stereo microphone with adjustable recording level is featured for the HD movie recording.


Shoot RAW images with your K-S1, or use the internal processing power to do in-body RAW development, HDR shooting, or utilize one of nearly 30 specialized picture and scene modes including Macro, Portrait, Moving Object, Night Scene Portrait, Surf & Snow, Kids, Pet, Food, Backlight Silhouette, Stage Lighting, Museum, and more. Who needs Instagram when you can add specialized effects to your art inside the camera with any one of a dozen options, from Faded Color to Vintage Color to Bold Monochrome, and others?


By combining some exclusive features of the big-brother K-3, as well as many proven internal features of the K-5/K-500 cameras, the new K-S1, with its LED-illuminated trim and buttons, is sure to turn heads while it captures great images.


The K-S1 body can be purchased from B&H as a body-only in Black, White, or Blue, or as a single-lens kit with a Pentax 18-55mm f/3.5-5.6 lens or a dual-lens kit with the 18-55mm and Pentax 50-200mm f/4-5.6 lenses. Continuing the colorful trend of Pentax's other DSLR lines, the K-S1 one-lens kits are available in Black, White, Blue, Cotton Beige, Denim Blue, Dusk Gold, Dawn Purple, Linen Brown, Midnight Black, Moon Silver, Sunset Orange, and Tweed Gray.

Pentax K-S1 DSLR Camera Body
Lens Mount K-Mount
Image Sensor APS-C CMOS Sensor
Effective Pixels 20.12MP 
Total Pixels 20.42MP 
Maximum Resolution 5472x3648
Aspect Ratio 3:2
Still Image File Format RAW (PEF/DNG), JPEG (Exif 2.30)
Storage Media SD, SDHC, SDXC (UHS-1 compliant), Eye-Fi Card, FLU Card 
Card Slot 1x SD Slot
Viewfinder Type Pentaprism
Frame Coverage 100%
Magnification 0.95x (w/ 50mm f/1.4 at infinity)
Eyepoint 20.5mm 
Diopter Adjustment -2.5m to +1.5m
Shutter Type Electronically controlled, vertical-run, focal plane shutter
Shutter Speed 1/6000 to 30 sec.
Flash Sync Speed 1/180 sec.
Drive Modes Single frame, Continuous (H, L), Self-timer (12s, 2s), Remote Control (0 Sec., 3
sec.), Exposure Bracketing
Top Continuous Shooting Rate 5.4 fps
Self-Timer 2 sec. and 12 sec.
Exposure Metering System TTL open aperture, 77 segmented metering 
Metering Method Multi 77, Center, Spot
Metering Range EV 0 to 22 (ISO 100, 50mm f/1.4)
Exposure Modes Program (P), Sensitivity Priority (Sv), Shutter Priority (Tv), Aperture Priority (Av), Shutter & Aperture Priority (TAv), Manual (M), Bulb (B), EFFECT, Scene (SCN), Auto Picture (AUTO), Movie
Exposure Compensation +/- 5 EV (1/3 and 1/2 steps)
Exposure Bracketing Yes. 3 frames, up to +/- 3 EV in 1/3 or 1/2 steps
ISO Sensitivity Auto, 100-51200 
Autofocus System TTL: phase-matching autofocus, SAFOX IX i+
Number of Focus Points 11 point (9 cross type focus points in the center)
Focus Modes Single AF (AF.S), Continuous AF (AF.C), Auto select AF (AF.A) 
Autofocus Sensitivity EV-1 to 18 (ISO 100 / at normal temperature)
Built-In Flash Yes. Retractable P-TTL pop-up flash
Flash Control P-TTL 
Flash Modes 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 Compensation -2 to +1 EV (1/3 steps)
Flash Bracketing Not Supplied by Manufacturer
External Flash Interface Hot shoe (P-TTL), high speed sync and wireless w PENTAX dedicated flash
White Balance Modes AUTO WB, Multi Auto WB, Daylight, Shade, Cloudy, Fluorescent Light (D: Daylight Color, N:
Daylight White, W: Cool White, L: Warm White), Tungsten Light, Flash, CTE, Manual WB, Color
Temperature Configuration, Copying the white balance setting of a captured image
White Balance Bracketing Not Supplied by Manufacturer
Movie Recording 1920x1080p at 30/25/24 fps, 1280x720p at 60/50 fps
Movie Metering TTL
File Format MPEG-4 AVC/H.264 (MOV)
Compression H.264 
Audio Recording Built-in stereo microphone
Audio File Format Not Supplied by Manufacturer
Maximum Recording Time 25 minutes maximum time per clip
Monitor 3.0” TFT color921k-dot LCD 
Interface USB2.0 (micro B, high-speed compatible), HDMI output terminal (Type D)
Wi-Fi Yes via Eye-Fi and FLU Cards
Power Source Rechargeable Li-Ion battery D-LI109
Battery Life Approximately 480 images
Operating Environment 32-104°F (0 to 40°C)
Dimensions 4.75 x 3.65 x 2.75” (12.1 x 9.3 x 7.0 cm)
Weight 19.7 oz  (558 g) with battery and memory card


The battery is listed as an "LI-109".  Is this a misprint?  I hope it is actually an LI-190, the same battery used in my K-3 as well as the K-5 and K-7.

According to Pentax’s site, their K-S1 will use the LI-109 battery.  This does not appear to be a misprint.  It is the same battery used by their K-r DSLR.

I wonder what we can expect in terms of weather sealing we've come to enjoy in many pentax models.

From all the current press releases and pre-views I've been able to find, there is not any mention of weather sealing on this model.  My hunch is that it does not have any special sealing, but this detail may come up as more information becomes available in the future.