Pentax 645Z vs Pentax K110D: A Deep Dive Comparing Two Pentax DSLRs Across Eras and Genres

Pentax’s camera lineup spans a remarkable range - from the very approachable, entry-level K110D to the heavyweight medium format powerhouse 645Z. Comparing these two is like sizing up a sprinter to a marathon runner: different tools for different missions, separated by almost a decade of technological evolution.

Having personally tested thousands of cameras throughout my career, including decades entrenched in Pentax systems, I find the 645Z and K110D form a fascinating study in contrasts. For readers weighing legacy, performance, and creative ambitions across broad photographic disciplines, I will unpack their core differences, synergies, and help you decide which may suit your style and workflow.

Let’s start by orienting ourselves with the physical and ergonomic dimensions.

Size and Ergonomics: Handling a Medium Format vs an Entry-Level DSLR

At first glance, the 645Z and K110D inhabit entirely different size universes.

The 645Z is a large, substantial body weighing about 1.55kg (3.4 lbs), roughly the heft of a brick with a dense grip. Its body dimensions (156 x 117 x123mm) mean it demands two hands and a deliberate shooting stance. True medium format cameras generally commit to a more robust body - a requirement both of the sensor size and the professional build standard, including environmental sealing.

In contrast, the K110D is compact and lightweight at 585g (1.29 lbs). It’s a traditional entry-level DSLR with dimensions 129 x 93 x 70mm, easy to pocket or sling around the neck for street and travel photography. For beginners or those prioritizing portability, the K110D feels nimble and unintrusive.

Pentax’s legacy ergonomic design principles shine in both models but cater to different handling styles. The 645Z provides a deep, contoured grip optimized for stability during long shoots or with heavy lenses, whereas the K110D offers straightforward, minimalist controls perfect for those focusing on learning or casual shooting.

This physical difference immediately speaks to their targeted user groups and shooting scenarios.

Top Controls and Interface: A Study in Intentional Design

Let’s pop the hood and check the controls and top panel layout.

The 645Z sports an advanced, professional-grade control cluster. You’ll find dedicated dials for ISO, exposure compensation, shutter speed, and aperture directly accessible, minimizing menu-diving. The top LCD gives an instant overview of shooting parameters - a feature geared to speed and precision in the field.

By contrast, the K110D’s more minimalist top deck echoes its budget focus. Controls are fewer, relying more on rear-menu navigation. The pentamirror viewfinder and simpler shutter speed dial suit entry-level users who may still be acquainting themselves with manual camera operation.

The 645Z’s array of buttons, though not touchscreen, is backlit for low-light visibility and offers customization. The K110D lacks this refinement, which is typical of cameras from its era, especially in the entry segment.

This disparity translates to real-world shooting: the 645Z affords rapid, intuitive adjustments critical in professional workflows, while the K110D requires more pause and menu gymnastics.

Sensor Technology and Image Quality: Medium Format vs APS-C CCD

Perhaps the most pivotal difference lies under the hood: sensor size and type.

The 645Z wields a 51.4-megapixel full-frame medium format CMOS sensor sized 44 x 33mm, roughly 3.9 times larger than a standard 35mm full-frame sensor. This beastly sensor area (1452 mm²) yields exceptionally high resolution (8256 x 6192 pixels) and stellar image fidelity.

It boasts notable features including:

• No anti-aliasing filter for maximum sharpness
• DXO Mark scores: overall 101, color depth 26.0 bits, dynamic range 14.7 EV, and low-light ISO effectiveness rated at 4505
• Native ISO 100-204800 for astounding flexibility, with clean noise characteristics throughout the range

Meanwhile, the K110D sports a modest 6.1-megapixel APS-C format CCD sensor (23.5 x 15.7mm). As a 2006-era entry-level sensor, it’s significantly smaller both physically and in pixel count (3008 x 2008 pixels).

The CCD sensor, while delivering pleasant color rendition and contrast, notably lags the CMOS tech in noise control and dynamic range. ISO tops at 3200, with native ISO 200 minimum limiting low-light versatility.

In real shooting, the 645Z offers superior detail, exquisite color depth, and highlight-to-shadow gradations, critical for portraiture, landscape, and any subtle tonality work. The K110D is serviceable for casual snapshots but falls short for professional-grade output, especially in challenging exposure conditions.

Back LCD and Live View: Modern Usability vs Basic Display

User feedback depends heavily on the rear screen and live preview capabilities.

The 645Z features a large, bright 3.2" tilting LCD with 1,037k-dot resolution. This aids precise image review, manual focusing assistance, and angled shooting. Live view mode incorporates phase detection AF for accuracy and speed.

Conversely, the K110D provides a tiny 2.5" fixed, 210k-dot LCD - a basic monitor primarily for image review rather than critical assessment. It lacks live view altogether, reflecting its generation’s technology limitations.

Tactile navigation on the 645Z’s button interface delivers a professional feel. The K110D’s minimal screen and absence of live view imply a more analog shooting experience that’s less forgiving for framing or focus checking on LCD.

For those used to contemporary DSLRs or mirrorless models, the 645Z’s screen and live view function become an essential productivity tool, particularly when shooting tethered or in studio environments.

Sample Image Quality Across Environments: Stunning Detail vs Basic Capture

What do these cameras actually produce? Here are side-by-side sample photos from both cameras:

Pentax 645Z front Pentax 645Z screen back Pentax K110D screen back

The difference is immediately obvious. The 645Z’s files exhibit razor-sharp detail and smooth tonal transitions, even under varied lighting conditions. Portrait skin tones look natural and nuanced; bokeh from medium format optics renders a creamy, professional background blur. Landscapes benefit from dynamic range that holds highlights and shadows with grace, while wildlife and sports shots captured with telephoto lenses retain clarity.

On the other hand, the K110D’s images are more modest - workable for web use and casual prints but lacking depth and subtlety. Color rendering is decent but comparatively flat; fine textures are smoothed by lower resolution.

This visual contrast underscores where each camera shines: the 645Z targeting pros and serious enthusiasts hungry for image quality, and the K110D catering to budget-conscious beginners or casual shooters.

Autofocus System: Snap, Track, and Shoot

How well do these beasts focus?

The 645Z contains a 27-point autofocus system mixing phase-detection and contrast-detection autofocus (CDAF) modes in live view. It supports continuous, face detection, selective AF with decent tracking capabilities, and an overall competent AF speed. While not the bleeding edge compared to mirrorless hybrids, it handles portraits and studio work confidently, and moderately fast action.

The K110D, by contrast, has an 11-point phase-detection AF system lacking live view AF or face detection. It offers continuous and single AF modes, but tracking capabilities are minimal. For fast subjects or wildlife, you’ll find it trails behind modern expectations.

In practice, the 645Z’s focusing system feels purposeful and reassuring, especially in controlled scenarios (e.g., portraiture, landscape). The K110D’s AF is more rudimentary - adequate for everyday snapshots but less reliable for sports or wildlife where speed and accuracy matter.

Burst Shooting and Buffer: Chasing the Action

When shooting sports or wildlife, burst rate can be decisive.

Both cameras clock a modest 3 frames per second continuous shooting speed. However, the 645Z, benefitting from a faster PRIME III processor, supports deeper buffers and faster write speeds to dual SD slots, supporting longer bursts of high-resolution RAW files.

The K110D’s buffer fills quickly due to limited internal processing power and single-slot storage. Its older USB 2.0 also limits tethering speeds.

Thus, while neither camera is a speed demon compared to modern sports DSLRs, the 645Z decidedly holds the upper hand for extended bursts or studio tethered shoots.

Video Capabilities: Modest Medium Format vs Entry-Level DSLR

Medium format traditionally eschews video as a primary focus, and the 645Z reflects that. It offers Full HD 1080p recording at 60i, but no 4K or advanced video features like log profiles or high frame rates. Audio input is supported via a microphone port, but no headphone out. Stabilization is absent.

The K110D predates video capture on DSLRs entirely, offering no movie mode.

For videographers, the 645Z provides the bare essentials for supplementary recording but cameras specializing in video will be far more suitable. The K110D is strictly a stills camera.

Connectivity, Storage, and Battery Life: Modern Profi Standard vs Basic Entry

Connectivity shows the generational gap starkly.

The 645Z features USB 3.0 for fast tethered transfers, HDMI output for external monitoring, and dual SD/SDHC/SDXC slots for backup and extended capacity. It supports optional GPS for geotagging and boasts weather sealing, freeze resistance, and dustproofing for rugged field use.

Battery life is excellent at around 650 shots per charge on the proprietary D-LI90 battery - well suited for prolonged outdoor or studio sessions.

The K110D, meanwhile, relies on 4 AA batteries - not rechargeable lithium-ion cells - resulting in modest battery life and heavier pack for the power. Storage accepts only SD/MMC cards and has a single slot. No video output or wireless features exist.

Environmental sealing is absent, which limits outdoor reliability.

This places the 645Z firmly in the professional workflow ecosystem, whereas the K110D embraces straightforward, casual shooting with minimal bells and whistles.

Build Quality and Durability: Bulky and Rugged vs Lightweight Simplicity

The 645Z’s magnesium alloy chassis and extensive weather sealing allow shooting in rain, dust storms, or subzero conditions - features critical for landscape professionals or serious field photographers.

The K110D, built primarily with plastic components, is suited for dry, controlled environments - the classroom, street photography on fair days, or home snapshots.

Lens Ecosystem and Compatibility: Locking Medium Format vs Versatile APS-C

Lens availability is another area where we see a gulf.

The 645Z uses the Pentax 645AF2 mount supporting a limited but high-quality range of six lenses designed specifically for medium format optics. These primes and zooms prioritize sharpness and optical performance tailored to the sensor size.

The K110D uses the popular Pentax KAF mount, compatible with over 150 lenses including primes, zooms, macro, and specialty glass produced over decades. This lens ecosystem lends flexibility for almost any discipline, from macro to telephoto sports lenses at accessible price points.

For photographers invested in lens variety and budget lens acquisition, the K110D is hard to beat. The 645Z’s specialized lens mount demands investment but rewards with exquisite image rendering.

Performance Scores and Evaluations: Summary Across Metrics

Let’s look at a scored overview assembling the technical and practical evaluations:

The 645Z unsurprisingly tops in image quality, dynamic range, color depth, and low-light performance. It wins hands-down on weather sealing, build quality, and professional features. Its weaknesses surround size, cost, and burst rate, which are limiting for some use cases.

The K110D scores low on almost all these except price and portability, making it an affordable option for beginners or those invested in Pentax’s K-mount legacy lenses.

Genre-Specific Performance: Which Camera Excels Where?

Here's a breakdown of how each camera fares in different photography types:

• Portrait: The 645Z delivers exquisite skin tones and creamy bokeh thanks to medium format optics; K110D is limited to basic results.
• Landscape: The 645Z’s dynamic range and resolution define it as a top choice; K110D struggles with detail and noise.
• Wildlife: Neither excels in fast action, but 645Z’s AF is better; K110D limited by slow AF.
• Sports: Lower frame rates on both; 645Z better autofocus tracking.
• Street: K110D’s small size and quiet operation give it an edge; 645Z is bulky and conspicuous.
• Macro: Pentax’s K-mount variety benefits K110D; 645Z’s medium format lenses offer sharpness but less magnification range.
• Night/Astro: 645Z shines with low noise at high ISO; K110D’s ISO 3200 max and noise limit its suitability.
• Video: 645Z offers basic 1080p video; K110D offers none.
• Travel: K110D favored for portability and weight; 645Z cumbersome but versatile for planned shoots.
• Professional Work: 645Z’s robustness, image fidelity, and workflow compatibility dominate; K110D is a learning tool or backup.

Real-World Recommendations: Who Should Choose Which?

• For professional photographers demanding top image quality, color fidelity, and durability - especially in studios, landscape, and portraits - the Pentax 645Z is a compelling medium format DSLR despite its bulk and price. Its rich sensor and rugged build enable work that smaller sensors cannot match.

• For enthusiasts on a budget, beginners learning DSLR fundamentals, or photographers prioritizing portability and lens ecosystem variety without critical image quality demands, the Pentax K110D remains a no-frills, affordable entry point into DSLR photography. Its simplicity appeals for casual use, travel, and street.

• For videographers, neither excels; the 645Z suffices for limited 1080p footage, while the K110D offers no video.

• For wildlife and sports action, the 645Z has modest autofocus and buffer advantages, but both will struggle with very fast subjects compared to newer cameras.

• For macro and close-up, the K110D’s extensive lens selection provides flexibility though resolution limits detail; 645Z delivers superior image quality but fewer macro options.

The Price-to-Performance Equation

At a current street price above $5,000, the 645Z commands a significant investment. This cost reflects its medium format sensor and pro-grade construction, justifiable for serious creatives or commercial work yielding high-value output.

The K110D, meanwhile, often found under $1,000 used, remains accessible. The price difference underscores their divergent markets and the rapid technological leap Pentax made between 2006 and 2014.

Final Thoughts: Evolution of a System, Not Just Shopping Choices

What this comparison reveals is more than specs side by side; it paints a portrait of Pentax’s evolution from a beginner-friendly, APS-C DSLR to a sophisticated medium format stalwart. The 645Z maintains relevant pro features and an exceptional sensor that hold up well even years after launch, whereas the K110D embodies a no-frills era of DSLR photography with strengths in simplicity and affordability.

Depending on your photographic ambitions and budget, these cameras represent bookends on the Pentax DSLR continuum. Those seeking stellar image quality, durability, and medium format excellence will find the 645Z meets and exceeds expectations. Those starting their photographic journey or needing a lightweight, affordable DSLR with strong lens legacy may find the K110D a faithful companion.

I hope this detailed comparison helps you chart your photographic pathway with clarity.

Summary of Key Specifications:

With this comparison, I invite photographers at all levels to weigh their priorities honestly - image quality vs portability, budget vs durability - and select the Pentax that best suits your photographic narrative. Each camera is a capable storyteller within its genre and era. Choose your pen wisely.