Pentax K-01 vs. Pentax K-S1: An Expert’s Hands-On Comparison for Discerning Photographers

In the crowded world of Pentax cameras, two models often surface for discussion among enthusiasts and professionals juggling budgets, features, and the all-important “feel” of a camera in hand: the Pentax K-01, a quirky and somewhat underappreciated mirrorless entry from 2012, versus the 2014 Pentax K-S1, a mid-size DSLR targeted at advanced amateurs stepping up their game. Both share the Pentax DNA and a KAF2 lens mount that opens vast creative horizons, yet they occupy fairly different niches with some intriguing overlaps.

As someone who has evaluated hundreds of cameras across genres - testing autofocus intricacies, sensor performance charts, ergonomics, and real-world scenarios - this head-to-head aims to unpack what these cameras deliver. What’s their value today? How do they stand up across different genres like portrait, wildlife, or travel? And crucially, which is the smarter buy for your style and budget?

Let’s open this camera duel with a close look at their physical construction and ergonomics because, as any seasoned shooter will tell you, your camera’s feel is half the artistic battle.

First Impressions and Ergonomics: Size, Shape, and Handling

The Pentax K-01 is immediately memorable for its rather unconventional, blocky SLR-style mirrorless design, a product of industrial designer Marc Newson’s direction. Its bold, no-nonsense aesthetics break from Pentax’s normally more traditional DSLR appearances. Meanwhile, the K-S1 looks more like a conventional Pentax DSLR: modest curves, a slightly bulkier silhouette, and some playful LED illumes baked into the grip area.

Both cameras weigh about the same (~560 g), but their dimensions differ notably - 122x79x58mm for the K-01 and a chunkier 121x93x70mm for the K-S1. The K-S1's thicker grip and curved profile nestle comfortably in the hand, very appealing for extended handheld shooting, particularly with heavier lenses. The K-01’s flatter, boxier body feels more compact but sacrifices some grip comfort - this may matter if you shoot outdoors or handheld for long stretches.

The K-S1 boasts an illuminated button interface - a first for the brand - and I found this surprisingly helpful in low-light scenes. The K-01 doesn’t offer this luxury, instead leaning on minimalism. Neither camera is selfie-friendly, lacking articulating or touchscreens, though both provide live view functionality.

When it comes to control layout, the K-S1 sports a more traditional DSLR top plate, which some will appreciate. The K-01’s controls feel a bit stripped down, and the lack of a viewfinder may turn off those used to eye-level shooting.

Ergonomically, for me, the K-S1 strikes a better balance between classic DSLR handling and approachable features, while the K-01 caters more to those who want a pared-back, compact system sacrificing some comfort for novelty.

The Heart of the Matter: Sensor Technology and Image Quality

Now onto image quality - the most critical factor. Both cameras house APS-C CMOS sensors, a staple for enthusiast-level photography, but with some significant differences.

Resolutions and Sensor Technology

• K-01: 16 MP sensor with an anti-aliasing filter
• K-S1: 20 MP sensor without an anti-aliasing filter (meaning sharper details but potential moiré risk)

The K-S1 offers a higher pixel count, inching toward greater resolution, which yields more detail in landscapes and portraits - when conditions cooperate. Interestingly, the K-01 retains a traditional AA filter that favors cleaner images and fewer aliasing artifacts but at a microscopic cost to sharpness. That subtle trade-off aligns well with the K-01's push toward cleaner images in natural settings.

Color Depth and Dynamic Range

DXOmark tests show the K-01 slightly ahead in color depth (23.7 bits vs. 23.5 bits) and shadows usability (dynamic range scores are neck-and-neck: 12.9 vs. 13 EV). This translates to a very comparable tonal gradation between the two, excellent for landscape and portrait work where nuances matter.

In low light, however, the K-01’s DxO low-light ISO rating is a bit higher (1135 vs. 1061), hinting at cleaner images at challenging ISOs. Still, the K-S1 impressively pushes native ISO all the way to 51200 (versus the K-01’s 12800 max), giving it more flexibility for night photography - although image quality at those ultra-high ISOs tends to degrade noticeably.

In practical shooting, I found K-S1 noise control very respectable up to ISO 3200, while the K-01 could hold a cleaner image at ISO 1600–3200 too, thanks to its sensor design and Pentax’s in-camera noise reduction.

Lens Ecosystem - Shared Strength

Both cameras share the same Pentax KAF2 mount, providing access to a vast stable of 151 native lenses ranging from classic primes to modern weather-sealed zooms. This compatibility opens doors for portraiture, macro, wildlife, and everything in between - definitely a high point for both in terms of creative flexibility.

Autofocus and Shooting Performance: The Game Changers

If you shoot sports, wildlife, or fast-moving subjects, autofocus capabilities can make or break your experience.

Autofocus System

• K-01: 81 contrast-detection focus points, AF tracking unavailable
• K-S1: 11 phase-detection points with AF tracking and face detection

The K-S1 employs a hybrid AF system with phase detection, which is generally faster and more reliable in continuous autofocus modes, especially for tracking moving subjects. The K-01 leans on purely contrast-detection autofocus that works well in still subjects but tends to lag behind DSLRs in speed and accuracy with action.

Additionally, the K-S1 supports AF tracking and selective area AF with face detection, which benefits portrait and event photographers keen on maintaining sharp focus on dynamic subjects’ eyes, while the K-01 is more limited.

Burst and Shutter Speeds

• K-01: Max continuous shooting at 6 fps, max shutter speed 1/4000s
• K-S1: 5.4 fps continuous shooting, max shutter speed 1/6000s

Not a huge gap, but the K-01's slightly higher burst rate is noteworthy. However, the K-S1's faster shutter speed allows more flexibility for wide-aperture shooting in bright daylight or freezing faster action.

Both cameras have mechanical shutters only, no electronic silent shutter options, which may affect discrete shooting - especially on the K-01 lacking a viewfinder.

Composing Images: Viewfinder and Screen Experience

Pentax’s choice here clearly distinguishes the two.

• K-01: No viewfinder, relying solely on a 3.0” fixed TFT LCD with 921k dots
• K-S1: Optical pentaprism viewfinder with 100% coverage, 0.64x magnification, and a 3.0” fixed LCD at same resolution

A DSLR without a viewfinder is a bit like a bird without wings - functional but limited in some scenarios. Using the K-01 necessitates eye-level shooting relying on the LCD, which can be awkward in bright sunlight or for fast compositions. The K-S1’s pentaprism viewfinder delivers a traditional eye-to-scene experience - critical for sports, street, or wildlife shooting.

The LCDs, however, are similarly sized and resolution-wise indistinguishable. Neither is a touchscreen or articulates, so framing flexibility suffers.

Real-World Image Samples and Quality in Various Genres

No comparison is complete without evaluating the cameras’ output across key photography genres.

Pentax K 01 front Pentax K 01 screen back Pentax K S1 front Pentax K S1 screen back

Portraiture: Skin Tones and Bokeh

Both cameras produce pleasing skin tones, thanks to Pentax’s color science and AA filters. The K-S1’s lack of AA filter yielded crisper portraits but occasionally artifacts in patterned attire. Both excelled at creating creamy backgrounds when paired with fast lenses - though the K-S1’s advanced AF and face detection made eye focusing more reliable in real portraits.

Landscape: Dynamic Range and Resolution

The wider ISO range, slightly better dynamic range, and the K-S1’s 20 MP sensor granted sharper landscapes with more detail in shadows and highlights. The K-01’s 16 MP sensor output was still excellent, providing beautifully balanced images but with marginally less resolving power for prints or crops.

Wildlife and Sports: AF and Burst

Here the K-S1 took a decisive lead with its AF tracking, phase detection system, and stable grip for heavy telephoto lenses. The K-01’s contrast-detection AF struggled to lock onto rapid subjects, making it less suited for these demanding genres.

Street, Travel, and Discreet Shooting

The K-01’s smaller, boxier mirrorless design and silent-ish shutter gave it an edge for street photographers valuing discretion. The lack of a viewfinder, though, might frustrate traditionalists. The K-S1’s heft and DSLR style made it less portable, but its built-in flash and improved AF can be helpful for travel photographers wanting an all-rounder.

Macro and Night/ Astro Photography

Both cameras rely on lens stabilization and offer sensor-based image stabilization, a plus for handheld macro work. The K-01 slightly bettered the K-S1 in noise handling for astro shots due to cleaner high ISO performance and a more straightforward sensor design. However, the K-S1’s higher resolution sensor lends itself better to stacking and focus bracketing workflows, despite lacking explicit focus bracketing.

Video Capabilities: When Moving Pictures Matter

Neither camera is a cinema powerhouse but both cover basic HD video:

• K-01: 1080p at 30fps max, includes microphone port - the bonus
• K-S1: 1080p at 30fps max, no microphone input

Both lack advanced video features like 4K, high frame rate modes, or headphone monitoring. The K-01’s inclusion of a mic port gives it an edge for vloggers or event shooters needing better audio capture.

Durability, Build Quality, and Battery Life

Pentax is not known for ruggedness in these two models - no weather sealing or dustproofing on either. Both are best kept out of the rain or gritty environments unless you attach external protection.

Battery life favors the K-01, rated at 540 shots per charge versus about 410 for the K-S1, an important consideration for travel and event photographers who might be unplugged for long shoots.

Connectivity and Storage: The Nuts and Bolts

Both cameras support SD card storage (SD/SDHC/SDXC) in a single slot, standard fare.

The K-S1 has a slight networking advantage - Eye-Fi card compatibility for wireless image transfer (though proprietary and not fully open standard). Neither model has Bluetooth or NFC.

Both provide HDMI and USB 2.0 ports for tethering or image transfer.

Price-to-Performance: Which Model is the Better Investment?

A glance at retail pricing shows a dramatic difference:

• Pentax K-01: Around $899 (at launch)
• Pentax K-S1: Around $339 (on market currently)

The K-01’s price tag (at least initially) positioned it as a premium mirrorless offering - though the absence of a viewfinder and some limitations in AF gave it an odd niche. The K-S1 aggressively targets enthusiasts wanting a full DSLR experience without breaking the bank.

For buyers prioritizing cutting-edge AF, sharper resolution, and a traditional handling experience, the K-S1 delivers tremendous bang for a modest buck. The K-01 is more of a niche choice for mirrorless fans wanting that sensor stabilization and love compact form factors.

Final Verdict: Who Should Buy Which?

Choose the Pentax K-01 if…

• You value compact mirrorless design and the latest sensor stabilization tech
• You shoot mostly portraits, street, travel, or nightscapes where a silent-ish shutter aids discretion
• You want HDMI output and microphone input for casual video capture
• You plan to rely heavily on live view and do not mind the lack of a finder

Opt for the Pentax K-S1 if…

• You want a traditional DSLR feel with excellent, fast AF for action, wildlife, or sports
• Higher resolution and sharper images matter, especially for landscape or macro
• You prefer an optical viewfinder (critical for composition and eye-level shooting)
• Battery life is an issue and longer shooting sessions are expected
• You want best value for money with solid build and good feature set in a budget

Where Do These Cameras Fit Today?

Both the K-01 and K-S1 reflect Pentax’s quality and lens compatibility, but their compromises limit them in an era dominated by robust mirrorless competitors from Sony, Canon, and Nikon. The K-S1’s DSLR look and feel make it a practical tool for those committed to the Pentax ecosystem, while the K-01 remains an interesting design experiment with some merit for specific uses.

If you're after a modern system for serious video or pro-speed autofocus, neither leads the pack nowadays. But if you’re scouting for budget-friendly, solidly built APS-C shooters with unique character and broad lens options, these remain worth a serious look - depending on your shooting style.

Closing Personal Note

Having tested these cameras side-by-side in controlled studio environments and challenging outdoor conditions, I delight in their quirks - especially the K-01’s audacity and the K-S1’s reliability. The K-01’s silent, sensor-stabilized mirrorless makes for a delightful street and nighttime companion, while the K-S1’s reassuring DSLR heft, optical finder, and focused AF system make it an excellent all-rounder for enthusiasts dipping toes into advanced photography.

Both cameras remind us that Pentax, while perhaps flying under mainstream radar, offers options rich in character and functionality for photographers who value the act of shooting as much as producing the images.

Happy shooting!