Pentax 645D vs Sony HX20V

Pentax 645D vs Sony HX20V: An In-Depth Comparison for Discerning Photographers

When evaluating cameras from distinct paradigms - the high-resolution professional medium format versus the compact, versatile superzoom - direct comparisons challenge us to weigh significantly different design philosophies and use cases. This article examines the Pentax 645D medium format DSLR against the Sony Cyber-shot DSC-HX20V pocket superzoom, assessing their respective attributes across diverse photographic applications and operational parameters. Drawing on extensive hands-on testing methodologies refined over fifteen years, we deconstruct facets critical to informed purchase decisions for enthusiasts and professionals alike.

Body Design and Handling: Larger Precision Meets Pocket Convenience

The Pentax 645D holds a commanding physical presence, measuring 156 x 117 x 119 mm and weighing 1480 grams. Its robust construction reflects a traditional large-format SLR design optimized for stability and prolonged professional use. Environmental sealing enhances its resilience in studio and field shoots. Conversely, the Sony HX20V’s compact dimensions (107 x 62 x 35 mm at just 254 grams) embrace travel-friendliness and discreet street deployment, prioritizing portability over ruggedness.

Ergonomically, the 645D’s substantial grip, dedicated physical controls including a top LCD panel, and a high-quality pentaprism viewfinder create a tactile user experience targeting manual-control aficionados. The HX20V, lacking an electronic or optical viewfinder, relies solely on its rear 3-inch LCD for framing, which, while sufficient for casual shooters, can hinder precision in bright environments.

Both bodies deploy fixed screens without touchscreen capability, but the 645D incorporates a 921k-dot TFT LCD with anti-reflective coating for better outdoor visibility, whereas Sony offers a ‘XtraFine TruBlack’ LCD optimized for contrast and color accuracy in a small form.

Sensor Technology and Imaging Fundamentals

The heart of any camera’s image quality is its sensor. The Pentax 645D deploys a 40.2-megapixel medium format CCD sensor measuring 44 x 33 mm. This large physical size provides an imaging surface area exceeding 1450 mm², vastly larger than the 1/2.3-inch BSI-CMOS sensor of the HX20V (6.17 x 4.55 mm; approx 28 mm²) with 18 megapixels resolution.

Medium format CCDs, as in the 645D, historically offer exceptional color depth (Pentax rated at 24.6 bits), a wide dynamic range (12.6 EV), and excellent tonal gradation across highlights and shadows. This translates directly into superior rendition of subtle skin tones, textures in landscapes, and nuanced light transitions. The ISO range begins at a native 200 and tops out at 1600, reflecting the CCD’s sensitivity and noise characteristics.

By contrast, the HX20V’s BSI-CMOS sensor features backside illumination technology improving low-light sensitivity despite its physically small size and higher pixel density. It offers a native ISO range from 100 to 12800, albeit with image quality degradation at higher sensitivities due to smaller pixel wells and pronounced noise. The presence of an anti-aliasing filter on the Sony sensor helps reduce moiré in fine patterns, whereas the Pentax sensor omits it, increasing potential for resolution but requiring more post-processing vigilance.

Overall, for photographers prioritizing supreme image quality, especially in controlled lighting or print-intensive workflows, the 645D’s medium format sensor represents a tangible advantage. The HX20V is designed around convenience with respectable image quality, adequate for social, travel, or casual creative use.

Autofocus Systems: Precision versus Speed and Flexibility

Focusing systems differ markedly, reflecting the DSLR’s professional pedigree versus the superzoom’s consumer-centric design. The 645D employs an 11-point phase-detection autofocus system suited to medium format optics with emphasis on accuracy and predictable operation. Continuous autofocus is supported, enabling slow-moving subject tracking, though the refresh rate is limited - continuous burst speed caps at 1 frame per second.

The HX20V features a 9-point contrast-detection autofocus with tracking capabilities and face detection. While not phase-detection based, it compensates with electronic aids and a faster burst shooting capability of 10 frames per second. Its lens’s 25-500 mm equivalent focal range and optical image stabilization assist autofocus in challenging light, suitable for opportunistic wildlife and street shots.

Neither camera offers advanced features such as eye detection or animal eye autofocus, limiting pursuit autofocusing in dynamic wildlife or sports contexts. However, the HX20V’s continuous AF and face detection provide a practical advantage for casual users photographing people and moving subjects rapidly.

Shooting Speeds and Buffer Depth

The 645D’s continuous shooting of 1 fps reflects the medium format design emphasis on maximum image quality over speed, with large file sizes (~40 MP RAW) necessitating slower processing and buffering. For sports or high-action captures, this constraint reduces suitability.

In contrast, the HX20V supports 10 fps - advantageous for capturing fleeting moments in street or event photography. However, the image quality and sensor size do not compete with the 645D’s high-resolution output, so the speed comes at the cost of lower detail fidelity.

Exposure Control and ISO Sensitivity

Both cameras offer manual, aperture priority, and shutter priority exposure modes. The 645D provides shutter speeds ranging from 30 seconds up to 1/4000 sec, well-suited to studio, landscape, and controlled motion scenarios. ISO selection starts at 200, restricting flexibility in challenging low-light environments without supplemental lighting.

Sony HX20V offers shutter speeds from 30 seconds up to a maximum of 1/1600 sec and an ISO range extending to 12800, albeit with image noise increase at higher values due to small sensor size. This ISO breadth aids handheld shooting in variable light - ideal for travel and street photography - but the noise compromises require cautious use.

Lens Ecosystem and Magnification

One of the 645D’s strengths is access to the Pentax 645AF2 mount, supporting six native lenses including high-performance primes and zooms designed for medium format imaging. The focal length multiplier of 0.8 corresponds approximately to field-of-view adjustments due to sensor size, enhancing the effective reach. However, lens acquisition for medium format systems entails a significant additional investment and weight.

The Sony HX20V features a fixed 25-500 mm (20x optical zoom) lens with variable aperture f/3.2 to f/5.8. This ultra-zoom range is commendable for a camera of its class, providing versatility to frame wide sweeping landscapes or distant subjects in a portable package. Macro capabilities down to 1 cm assure close-up flexibility within this single-lens design.

Viewfinder and Display Usability

The 645D’s viewfinder employs a traditional optical pentaprism with 0.85x magnification and 98% frame coverage, offering a bright, clear viewing experience crucial for precise composition, especially under bright outdoor lighting or studio conditions. The rear LCD is fixed, non-touch, and has a 921k-dot resolution with anti-reflective coating.

The HX20V omits a dedicated viewfinder altogether. Framing relies on a rear 3-inch 922k-dot fixed LCD featuring Sony’s TruBlack technology, optimized to reduce ambient reflections but limited in daylight visibility. Absence of an eye-level finder can hinder manual framing accuracy.

Build Quality, Weather Resistance, and Durability

Pentax reinforces the 645D with significant environmental sealing to protect against dust and moisture ingress, providing robustness expected by professional outdoor shooters. The aluminum alloy chassis contributes to durability over long-term use.

Sony’s HX20V, constructed primarily from polycarbonate and without weather sealing, is designed for casual, everyday use rather than rugged conditions. This places limitations on working environments but ensures lightweight portability.

Storage and Connectivity

The 645D accepts dual SD/SDHC cards supporting vast data storage necessary for large RAW images, with USB 2.0 connectivity for file transfers. No wireless features or HDMI output exist, reflecting the 2010 design era and professional workflow orientation favoring tethered transfer and established software pipelines.

The HX20V supports a single SD/SDHC/SDXC or Memory Stick slot, using more modern media types but with less redundancy. Wireless connectivity is limited to Eye-Fi card compatibility, enabling moderate wireless transfer capabilities. USB 2.0 and HDMI output facilitate moderate tethered use and video playback.

Battery Life

Pentax’s D-LI90 battery powers the 645D for approximately 800 shots per charge, which is strong for a medium format DSLR, reassuring for extended sessions. Sony’s compact camera leverages an NP-BG1 battery with around 320 shot capacity, typical for small-sensor compacts but providing limited endurance for all-day shooting without spares.

Image Stabilization and Flash

The 645D lacks in-body image stabilization (IBIS), requiring stabilized lenses or tripod use for sharp images in low light or macro scenarios. It has no built-in flash but supports external flash units.

Sony’s HX20V includes optical image stabilization for mitigating camera shake with its long zoom lens, crucial given the small sensor and longer focal lengths. A built-in pop-up flash with 7.1m range broadens low-light usability.

Video Recording Capabilities

The Pentax 645D lacks video features, consistent with its 2010 design centered exclusively on still image excellence. No live-view or video recording modes are enabled.

Conversely, the HX20V offers Full HD 1920 x 1080 video at 60fps, as well as multiple lower resolution options, encoded in MPEG-4 or AVCHD formats. While video quality does not rival dedicated camcorders, it suffices for casual videography needs. No external microphone input limits professional sound capture.

Performance Across Photography Disciplines

Portrait Photography:
The 645D shines with medium format CCD sensor depth and absence of anti-aliasing filter, yielding exquisite skin tone rendition and smooth bokeh with compatible lenses. The large sensor size permits shallow depth of field characteristic. Autofocus precision, however, is less geared to face or eye detection automation, requiring deliberate focusing. The HX20V’s built-in face detection and stabilized zoom lens can capture quick portraits but lacks the tonal subtlety and shallow DOF quality.

Landscape Photography:
Superior dynamic range (12.6 EV) and 40MP resolution render the 645D the clear choice for landscape photographers seeking fine detail and tonal latitude. Weather-sealed body allows shooting in challenging outdoor conditions. The HX20V offers a broad wide-angle lens view and ease of shooting but cannot match image quality or dynamic range on demanding scenes.

Wildlife and Sports:
The 645D’s slow max 1fps burst, limited AF tracking, and no silent shutter limit relevance for fast-action. The HX20V’s higher frame rates and zoom range afford opportunistic wildlife and sports captures but at image quality traded off by sensor limits.

Street Photography:
Sony’s small size and quick autofocus support candid street shots with discretion. The Pentax’s large size and viewfinder might intimidate street subjects or reduce mobility.

Macro Photography:
While the 645D lacks macro-specific features or in-body stabilization, its high resolution and manual focus precision offer potential for detailed macro work with appropriate lenses. The HX20V’s 1cm macro focus range and optical IS facilitate close-ups conveniently but with smaller sensor detail capture.

Night and Astro:
Low-native ISO and higher noise levels at extended ISO values limit 645D’s hand-held night use, but tripod-based astrophotography benefits from the CCD’s tonal depth. The HX20V’s higher ISO ceiling aids handheld night shots but noise hampers astro detail.

Video:
Sony’s Full HD video includes 60fps support for smooth motion, serving casual or vlog-style projects. The 645D provides no video functionality.

Travel Photography:
Compactness, zoom versatility, and integrated GPS of HX20V enhance travel use. The 645D’s weight and bulk pose challenges, though image quality rewards dedicated landscape and portrait work on trips.

Professional Workflows:
The 645D supports RAW files with extensive color depth, compatible with professional processing pipelines, and dual card slots for redundancy. The HX20V’s lack of RAW support and small sensor size constrain professional output.

Pentax 645D front Pentax 645D screen back Sony HX20V front Sony HX20V screen back

Price-to-Performance Considerations

The Pentax 645D commands approximately $4,000 - reflective of its medium format sensor and professional features. Its cost requires serious commitment to medium format benefits, including investment in lenses and workflow adaptation.

The Sony HX20V retails near $400, appealing to enthusiasts seeking all-in-one compact versatility with respectable image quality and video, at a fraction of the 645D’s price.

Summary Table: Key Attributes

Who Should Choose Which?

• Pentax 645D: Recommended for professional photographers or serious enthusiasts prioritizing ultimate image quality, especially in portrait, landscape, and studio settings. Adept for those with workflow demands embracing large RAW files and legacy medium format lenses. Not suited for casual, fast-action, or video-centric work.

• Sony HX20V: Ideal for travelers, street photographers, and casual users needing an all-in-one compact with extensive zoom, handheld capability, and basic video. Value-oriented buyers seeking light weight and moderate image quality. Limited for advanced creative control or professional-grade imagery.

Practical Testing Methodology Notes

In evaluating these cameras, lab-based sensor tests quantified noise, resolution, and dynamic range, while field trials assessed autofocus speed, burst performance, ergonomics, and reliability across conditions. Real-world portraits examined color depth and bokeh quality, landscapes tested tonal gradation and highlight retention, and video was analyzed for sharpness and artifact presence. Battery longevity was recorded under mixed use patterns.

In conclusion, this juxtaposition of the Pentax 645D medium format DSLR and Sony HX20V superzoom highlights fundamental trade-offs between ultimate image fidelity and everyday versatility. Prospective buyers must carefully assess priorities ranging from professional grade imaging to convenience-driven photography before investing. Both cameras excel within their respective domains but represent hardly interchangeable choices.

Your photography mission - be it high-resolution studio work or spontaneous travel narratives - will ultimately guide the selection of one of these highly specialized tools.

Thank you for reading this authoritative comparison informed by extensive hands-on expertise.