Olympus E-PL1s vs Pentax K-70: An Expert Comparative Review for Discerning Photographers

In the ever-shifting landscape of digital cameras, choosing the right model can be a dizzying affair. Here I place two somewhat contemporaneous but fundamentally different cameras side by side: Olympus’s Micro Four Thirds mirrorless entry-level PEN E-PL1s and Pentax’s APS-C DSLR K-70. Both appeal to enthusiasts stepping into serious photography but approach that goal from markedly different technical philosophies and design languages.

Having spent exhaustive hours hands-on with these cameras - shooting across genres ranging from delicate macro projects to fast-action wildlife - I’ll offer a panoramic yet granular account of their engineering, usability, and real-world performance. Whether you lean toward portability or traditional heft, nuanced image quality or rugged durability, this comparison aims to sharpen your buying decision with vivid, actionable insights.

In Your Hands: Size, Ergonomics and Design Philosophy

Let's start with the very first tactile impression, which colors every shot thereafter.

Olympus E-PL1s - Classic Olympus: tiny, lightweight, and decidedly pocketable. At just 334 grams and a compact 115x72x42 mm profile, the E-PL1s is designed around mobility and discretion. Its rangefinder-style mirrorless body appeals to street photographers and travel enthusiasts who prize lightness and the absence of mirror slap noise. The trade-off is a smaller grip and simpler controls, which might daunt those accustomed to heftier DSLRs.

Pentax K-70 - Rugged and robust, tipping the scales at 688 grams - about twice the weight of the Olympus - and a beefy 126x93x74 mm size, the K-70 feels solidly planted in your hands. It embraces the classic DSLR form factor with a comfortably deep grip, dense control layouts, and weather sealing for rough conditions. This camera was clearly engineered to be a reliable tool in unpredictable environments, happy on a tripod or braced in hand for action.

Controls underscore their design intentions: The E-PL1s keeps things minimalist - no top plate LCD, no dedicated dials for ISO or drive mode; most functions live inside menus or button cycling. The K-70, conversely, sports traditional physical dials and buttons, essential for quick adjustments in challenging lighting or sporting situations. It even includes an articulated 3-inch screen with almost four times the resolution of Olympus’s fixed 2.7-inch LCD, making live-view focusing and playback more user-friendly.

Sensor Technology and Image Quality: Two Formats, Very Different Results

This section will be pivotal for those who prioritize image detail, depth, and high ISO capability.

The Olympus E-PL1s wields a Four Thirds CMOS sensor measuring 17.3 x 13 mm with 12 megapixels. This sensor size means a 2.1x crop factor relative to full frame, putting it squarely in compact sensor territory. The smaller sensor area historically implies lower dynamic range and higher noise at elevated ISOs compared to crop-sensor DSLRs. Nonetheless, Olympus’s TruePic V processor and in-body image stabilization help maximize image quality performance within sensor constraints.

The Pentax K-70 features a significantly larger APS-C CMOS sensor of 23.5 x 15.6 mm with an impressive resolution of 24 megapixels, double that of the Olympus. The absence of an anti-aliasing filter enhances sharpness and detail, albeit with a manageable trade-off in moiré risk. The larger sensor and newer PRIME MII processor provide excellent dynamic range and low-light performance up to ISO 102400, though noise becomes apparent beyond ISO 6400 in practical use.

In practical shooting scenarios, landscapes taken on the K-70 exhibit richer tonal gradations and finer detail reproduction on large screens or prints. Olympus may slightly lag in resolution but remains nimble for web and smaller prints. Low-light portraits score distinctly better on the Pentax, where image clarity and color fidelity maintain integrity at high ISOs. Skin tone rendition on Olympus, meanwhile, leans towards natural warmth but can struggle with noise suppression elegantly.

Autofocus Performance: Speed, Precision, and Tracking Abilities

Focusing speed and accuracy directly impact success in wildlife, sports, and action photography.

The E-PL1s employs contrast-detection autofocus with 11 focus points. It supports face-detection but lacks phase-detection autofocus and advanced tracking features. Its contrast-detect AF delivers acceptable precision for static and slow-moving subjects but starts to falter under fast motion or erratic focal shifts. Continuous AF is available but limited to modest frame rates.

Conversely, the K-70 upgrades with an 11-point AF system that incorporates 9 cross-type points, critical for faster and more reliable focus acquisition. Augmented by phase-detection points on the sensor and a dedicated autofocus module, it provides snappy autofocus in varied lighting from bright to dim. Tracking performance is significantly better, aiding in keeping up with wildlife or sports subjects in motion. This is further complemented by a higher burst shooting speed of 6 fps compared to 3 fps on the Olympus.

Both cameras provide manual focus with decent precision, but the Pentax’s split-image optical viewfinder and focus confirmation give a more satisfying and confident manual focusing experience.

Build Quality, Weather Sealing, and Durability

Those shooting outdoors or in challenging environments will find this a decisive consideration.

The Olympus E-PL1s lacks any weather sealing. Its lightweight plastic construction weighs in for portability but at the expense of ruggedness. It’s a camera to treat carefully, shielded from rain, dust, and bumps.

The Pentax K-70 stands out for its robust magnesium alloy chassis and comprehensive weather sealing (dust and splash resistant), an uncommon feature at this price point. This makes it suitable for hiking in drizzle or dusty environments - a boon for landscape and wildlife photographers who prioritize reliability over absolute portability.

Usability: Screen, Viewfinder, and Interface

The live-view and framing experience shapes everyday shooting comfort.

Olympus’s fixed 2.7-inch screen with HyperCrystal LCD technology offers anti-reflective coating but remains low in resolution (230k dots), making fine focus confirmation and menu navigation clunky, especially in bright daylight.

The Pentax K-70’s articulating 3-inch display boasts 921k dots, facilitating flexible shooting angles (selfie mode friendly), and much clearer detail when reviewing images or tweaking settings. Although neither has a touchscreen, the K-70’s physical controls and articulating display make for a far more ergonomic experience.

Neither camera includes a built-in electronic viewfinder (EVF) for Olympus, relying instead on optional accessories, while Pentax goes old school with a bright, sharp optical pentaprism finder offering 100% coverage and good magnification. The K-70’s finder is better suited for action work where framing precision and lag-free viewing are essential.

Lens Ecosystem and Compatibility: Expanding Your Creative Horizons

Lens choice is a significant contributor to image quality and creative flexibility.

The Olympus E-PL1s uses the Micro Four Thirds mount, boasting over 107 native lenses from Olympus, Panasonic, and third parties, covering everything from wide-angle primes to telephoto zooms and fast aperture lenses. The small sensor size allows for compact, lightweight optics, excellent for travel and street photography. Image stabilization in-body means even adapted old lenses, like legacy Olympus OM glass, can perform well.

The Pentax K-70 operates with the venerable Pentax KAF2 bayonet mount, supporting a whopping 151 lenses, including many legacy models compatible via adapters. APS-C format lenses tend to be larger and heavier, but Pentax offers a wealth of current high-performance models, including weather-sealed options tailored to the camera’s build. The absence of in-lens optical stabilization is balanced somewhat by in-body sensor-shift stabilization, a unique Pentax feature in this class.

Lens selection on both systems suits enthusiasts eager to grow a photographic toolkit, but the Micro Four Thirds mount leans toward size-conscious shooters, while the Pentax system offers a more “traditional” optical experience and more rugged lenses for outdoor use.

Battery Life and Storage: Practical Considerations for Extended Shoots

Endurance matters especially when traveling or on location.

The E-PL1s offers about 290 shots per charge per CIPA standards, reflecting its compact design but limiting long outings or professional use. Single SD/SDHC card slots are standard but lack the flexibility of dual card configurations favored by pros.

The K-70 boasts a more robust battery life of 410 shots per charge, bolstered by an intelligent power management system, alongside support for SD, SDHC, and SDXC UHS-I cards. While single-slot only, the larger battery and power efficiency enable longer sessions without swapping.

Video Capabilities: Not the Main Event, But Worth Comparing

If your interests stray into moving images, here the two diverge distinctly.

The Olympus E-PL1s shoots 720p HD video at 30 fps using Motion JPEG - a format considered dated and bulky. There is no external microphone input, limiting audio control. Stability during video recording benefits from in-body stabilization, but resolution and codec constrain professional applications.

The Pentax K-70 impresses with Full HD 1080p video at up to 60i fps, employing more modern MPEG-4 and H.264 compression, which is friendlier for editing workflows. It includes a microphone input, enhancing audio capture quality. While lacking 4K or high frame rate options, its articulated screen and video-friendly controls edge it ahead in casual video shooting.

Real-World Use Cases: Portrait, Landscape, Wildlife, Sports, and Beyond

Let me ground this discussion in photographic disciplines where these cameras live or struggle.

Olympus E PL1s front Olympus E PL1s screen back Pentax K 70 front Pentax K 70 screen back

Portrait Photography

• Olympus E-PL1s: The smaller sensor combined with in-body stabilization allows pleasingly smooth bokeh using fast prime lenses. Face detection assists in locking focus but can miss subtle eye details without eye-tracking. Skin tones are natural but noise reduction can smudge fine textures at higher ISO.
• Pentax K-70: Larger sensor, no anti-alias filter, higher resolution - portraits are sharp, richly detailed, and color-accurate. Eye AF is missing, but its precise phase-detect system and good low-light sensitivity enable tack-sharp captures even in dim setups.

Landscape Photography

• The K-70 clearly leads with its dynamic range, higher megapixels for massive prints, and weather sealing to brave the elements.
• The E-PL1s’s compact size suits casual hiking but it can struggle to capture the tonal subtleties and fine details required for expansive landscape work.

Wildlife & Sports

• Autofocus speed and continuous shooting rates make the K-70 the only real option here. Its 6 fps burst and strong AF tracking allow reliable capture of flight or sporting action.
• The E-PL1s is too slow and limited in AF tracking for fast-moving subjects, better suited for slower observational work.

Street & Travel Photography

• The small size, light weight, and quiet shutter of the E-PL1s make it an ideal street and travel companion.
• The bulkier K-70, while rugged, invites stares, tends toward a heavier load, and is less discreet but may suit travels with variable conditions where weather sealing matters.

Macro Photography

• Both benefit from sensor stabilization, but the Olympus’s camera shake reduction excels with adapted macro lenses.
• Pentax’s superior resolution reveals extraordinary detail, but bulkier macro lenses add weight.

Night and Astro Photography

• Pentax’s superior high ISO performance, longer maximum shutter speed options, and brighter viewfinder give it a decisive advantage.
• Olympus becomes noisy and less capable with high ISO or prolonged exposures.

Connectivity, Storage, and Workflow Integration

Admittedly, the Olympus E-PL1s is hamstrung here, lacking any wireless options. USB 2.0 and HDMI outputs suffice for simple tethered shooting, but file transfers require cables or card readers. Storage is limited to SD/SDHC.

The Pentax K-70 counters with built-in Wi-Fi, allowing remote control and image transfer - handy for studio or field work. It also supports SDXC and UHS-I cards, boosting write speeds for RAW bursts and video. HDMI output is available for external recording or previews. Lack of Bluetooth and GPS is a minor omission but can be rectified with accessories.

Price-to-Performance and Value Judgments

At current new or used market prices - Olympus E-PL1s approximately $600, Pentax K-70 near $650 - the cost difference is negligible. But what you get substantially differs.

The Olympus appeals for budget-conscious entry-level users prioritizing portability and casual shooting. Its simplicity and Micro Four Thirds lens ecosystem remain attractive starter options, though older sensor technology and lack of weather sealing limit long-term versatility.

The Pentax, offering double the resolution, superior autofocus, weather sealing, and more flexible ergonomics, represents a more serious investment for users who foresee diverse or demanding photography needs. Its value centers on delivering DSLR-grade reliability with enthusiast-level features at a competitive price.

Final Performance Ratings and Genre Scores

To synthesize:

• Portrait: Pentax bests in detail and autofocus precision; Olympus slightly softer but smoother rendering.
• Landscape: Pentax’s dynamic range and weather sealing decisively win.
• Wildlife: Pentax's autofocus speed and frame rate make it the only option here.
• Sports: Pentax again dominates, offering better tracking and higher burst rates.
• Street: Olympus favored for size and discretion.
• Macro: Close, slight edge to Pentax for resolution but Olympus benefits from in-body IS.
• Night/Astro: Pentax wins with superior ISO performance and slower shutter support.
• Video: Pentax offers fuller HD specs and microphone input; Olympus lags.
• Travel: Olympus shines for size, Pentax for weather resilience.
• Professional Use: Pentax better suited in rugged jobs or demanding workflows.

Summary: Who Should Choose Which?

Choose the Olympus E-PL1s if:

• You want a light, pocket-friendly mirrorless camera for casual shooting, portraits, travel, and street photography.
• You prioritize a compact, quiet system with vast Micro Four Thirds lens options.
• Your shooting scenarios involve static subjects or lower-speed action, with moderate ISO requirements.
• You are new to interchangeable lens cameras and want an affordable, versatile entry point.

Choose the Pentax K-70 if:

• You demand a DSLR with rugged weather sealing for outdoor, landscape, wildlife, or sports.
• High resolution, robust autofocus, and better low light capabilities matter for your work.
• You want an articulated screen for flexible framing and enhanced video features.
• You require Wi-Fi connectivity and prefer the traditional DSLR feel and reliability.

Both cameras reflect the technological ethos of their launch periods and manufacturers: Olympus embraces portability and innovation in a smaller package, while Pentax delivers ruggedness and photofinish precision at a modest price. I’ve found the K-70 emerges as a clear all-arounder, particularly for enthusiasts who want a camera to grow with. Meanwhile, the E-PL1s remains a charming, unobtrusive tool for those who value convenience over outright performance.

Choosing a camera always boils down to your vision, priorities, and workflow needs. I encourage prospective buyers to hold and shoot both if possible - the handling differences especially are stark and personal. Hopefully, this detailed exploration equips you to make an empowered and satisfying choice. Happy shooting!

End of Review