Sony RX100 vs Sony A33: An Exhaustive Comparison for Photography Enthusiasts

As seasoned camera testers with over fifteen years of hands-on evaluation across a myriad of photography genres, assessing the Sony Cyber-shot DSC-RX100 ("RX100") and Sony SLT-A33 ("A33") offers a compelling journey into two distinct segments of Sony’s photographic lineup. Released in 2012 and 2010 respectively, these models reflect divergent design philosophies: the RX100 as a pioneering large-sensor compact camera, and the A33 as an innovative entry-level DSLR (technically an SLT). This in-depth comparison aims to help enthusiasts and professionals clarify which model aligns best with their creative ambitions, drawing upon extensive technical analysis, real-world field testing, and nuanced understanding of photographic requirements.

First Impressions: Size, Ergonomics, and Build

Physically, these cameras cater to different priorities. The RX100 is a compact powerhouse, measuring a neat 102 x 58 x 36 mm and weighing just 240 grams, making it eminently pocketable - a key consideration for travel or street photographers valuing portability without sacrificing sensor capability. The A33 is significantly larger at 124 x 92 x 85 mm and 500 grams, reflecting its DSLR lineage with more substantial grip and heft intended to facilitate stable handling, especially with longer lenses.

Ergonomics on the A33 benefit from traditional DSLR-style controls, a fact evidenced when comparing the top-plate layouts:

The A33 incorporates a mode dial, dedicated exposure compensation dial, and customizable buttons. Its fully articulating 3-inch screen (921k pixels) offers versatile shooting angles and selfie friendliness, appealing to videographers and vloggers, whereas the RX100’s fixed 3-inch, 1229k-pixel WhiteMagic TFT LCD foregoes articulation but delivers crisp daylight visibility. The RX100’s minimalist control scheme suits spontaneous shooting but lacks the manual dials and buttons found on the A33.

Both cameras lack weather sealing or ruggedization, limiting their use in harsh environments, but the A33’s more robust build generally inspires greater confidence for demanding fieldwork.

Sensor Technology and Image Quality: The Heart of the Matter

A critical determinant of output quality, sensor size and technology set the tone for each camera’s photographic potential. The RX100 employs a 1-inch CMOS sensor measuring 13.2 x 8.8 mm, packing 20 megapixels. Balanced against the 24x36mm “full frame” standard, this sensor is substantial for a compact but still physically smaller compared to the A33’s APS-C CMOS sensor at 23.5 x 15.6 mm with 14 megapixels.

Despite having fewer pixels, the A33’s sensor area of 366.60 mm² is more than triple the RX100’s 116.16 mm², resulting in inherently superior light-gathering capacity. In controlled testing, this translates to better image quality in dynamic range, color depth, and high ISO performance - metrics captured quantitatively in their DxO Mark scores with the A33 scoring an overall 70 versus the RX100’s 66.

This advantage manifests most prominently in low-light scenarios and landscape photography, where nuanced tonal gradations and shadow detail become critical. The A33’s maximum native ISO tops out at 12,800 (expandable to 25,600), providing usable noise performance up to ISO 1600-3200 in real scenarios. By contrast, the RX100’s native ISO extends to 25,600 but its smaller sensor limits practical usability to around ISO 800-1600 before noise becomes intrusive.

User Interface and Viewing Experience

Comfort and convenience during shooting affect the photographic experience profoundly. The A33’s electronic viewfinder (EVF) features an equivalent 1,150k-pixel resolution, covering 100% frame and offering 0.73x magnification. This EVF is a clear strength for precise framing, especially in bright conditions where LCDs may falter. The RX100 lacks an EVF, relying exclusively on its LCD. This absence can create challenges in glaring outdoor conditions or prolonged shoots requiring strain-free eye-level composition.

The RX100’s LCD benefits from the WhiteMagic technology that boosts brightness and outdoor legibility despite the lack of articulation, while the A33’s fully tilting screen caters better to low-angle, high-angle, and selfie-style shooting. Notably, neither has touch capabilities, a feature more critical in newer models but less so here.

Autofocus Systems: Speed, Accuracy, and Tracking

Sony’s autofocus (AF) technology within these cameras displays signature divergence - the RX100 employs a contrast-detection AF system with 25 focus points, including face detection and AF tracking, designed primarily for stills and rapid capture in the compact segment. In contrast, the A33 utilizes Sony’s patented Translucent Mirror Technology (SLT) with a hybrid phase-detection AF system, offering 15 focus points (3 cross-type) and the advantage of continuous phase detection during live view.

Practically, the A33’s phase detection affords more reliable subject tracking in sports and wildlife scenarios, albeit with fewer AF points than modern standards. The RX100’s higher burst rate at 10 fps with AF tracking compares favorably against the A33’s 7 fps but sensitivity and accuracy of subject acquisition favor the A33’s hybrid system when paired with compatible lenses.

Neither camera supports eye AF or animal eye AF, which are now standard in contemporary models but were unavailable at their release time. Focus precision at macro distances slightly favors the A33 owing to lens selection flexibility, though the RX100’s fixed lens has a commendable 5cm macro close-focusing capability for casual close-ups.

Lens Ecosystem and Versatility

The RX100’s fixed lens delivers a versatile 28-100mm equivalent zoom range with a fast F1.8-4.9 aperture - excellent for low-light shooting and shallow depth-of-field effects in a compact package. Its lens is optically stabilized, enhancing handheld shooting reliability. However, the fixed lens constrains flexibility; users desiring specialty optics (ultra wide, super telephoto, prime lenses) will find themselves limited.

Conversely, the A33 accepts over 140 Sony and third-party Alpha mount lenses, spanning macro, ultra wide, telephoto, tilt-shift, and cinema-quality optics. This adaptability significantly broadens creative potential spanning almost all photographic genres. Additionally, sensor-based image stabilization in the A33 benefits any lens mounted, a critical edge for legacy or specialty glass without built-in stabilization.

Sony RX100 front Sony RX100 screen back Sony A33 screen back

Real-World Image Quality Across Photography Genres

Portraits: Skin Tone, Bokeh, and Detection

Portrait photographers demand natural skin tones and pleasant subject separation. The A33’s larger APS-C sensor excels at producing creamy bokeh and fine tonal gradation, delivering images with natural warmth and smooth defocusing paths through fast-prime lenses like the Sony 50mm f/1.8. Meanwhile, the RX100’s bright F1.8 aperture helps achieve background blur but its smaller sensor limits bokeh quality and dynamic range, occasionally rendering images with slightly less dimensionality.

Face detection on both cameras works reliably in good light, but the A33’s ability to pair with quality prime lenses enhances eye catchlight and overall portrait impact. However, for casual portraiture on the move, the RX100’s freedom and pocketability might outweigh the bokeh advantage.

Landscape: Detail, Dynamic Range, and Durability

For landscapes, resolution and dynamic range are paramount. The A33’s 14 MP APS-C sensor yields detailed output with excellent highlight recovery thanks to a wider dynamic range (~12.6 EV vs 12.4 EV on the RX100). The RX100’s 20 MP sensor captures higher nominal resolution but compromises in tonal subtleties when shadows or bright skies dominate.

Neither camera offers weather sealing or ruggedness, so protective measures are necessary in inclement conditions. Landscape photographers prioritizing ultimate image quality will find the A33’s files more flexible in processing.

Wildlife and Sports: Autofocus and Speed

Autofocus speed and tracking are essential for capturing wildlife or fast action. The A33’s SLT phase-detection autofocus, while modest in coverage (15 points), provides excellent continuous AF for moving subjects - a boon with appropriate telephoto lenses. Its 7 fps burst rate is adequate but not class-leading.

The RX100’s 10 fps shooting rate with AF tracking exceeds the A33 numerically, yet its smaller sensor and zoom range limit telephoto potency. Wildlife photographers, therefore, favor the A33 with a quality telephoto zoom.

Street and Travel Photography: Discretion, Weight, and Practicality

In candid street shooting and travel, the RX100 shines due to its small footprint and virtually silent operation. It slips into a jacket pocket effortlessly, enabling spontaneous captures without the obtrusion of a bulkier rig. The absence of an EVF and fixed lens restrict compositional flexibility but the camera’s rapid responsiveness (fast startup, high burst with AF) supports decisive moments.

In contrast, the A33, while more versatile, can feel cumbersome for discrete usage and long handheld walks, with a weight penalty and volume dissuading minimalist setups. Yet its articulating screen supports creative framing inaccessible to the RX100.

Battery life is comparable - RX100 rates about 330 shots, and A33 slightly better at 340 shots per charge - ensuring a full day for most casual to moderate shooting loads.

Macro and Close-Up Imaging

While neither camera is specialized macro equipment, the A33’s ability to leverage dedicated macro lenses confers an advantage in magnification and focusing precision. Conversely, the RX100’s lens allows respectable close focusing at 5cm, suitable for casual macro but lacking the magnification and working distance of true macro optics.

Image stabilization (optical in RX100, sensor-shift in A33) assists hand-held macro shots on both platforms, though the A33’s versatility in lens choice tip the scales further for serious macro enthusiasts.

Night and Astrophotography: High ISO and Long Exposure

The A33’s improved low-light ISO score (591 DxO low-light ISO versus 390 for RX100) enables cleaner images at elevated ISOs. Its longer maximum shutter speed (30s on both) accommodates night sky imaging with tripod use; however, lack of built-in bulb mode limits extended exposures without remote control or firmware hacks.

The RX100’s optical stabilization offers limited boon for handheld night shots but its smaller sensor hampers noise performance above ISO 1600.

Video: Capabilities and Limitations

Both cameras record Full HD video (1920 x 1080), with the RX100 capturing video at 60p max and the A33 also supporting 60 and 29.97 fps, advantaging smooth motion rendering.

A notable advantage of the A33 is its microphone input port, affording external audio capture critical for professional video work - absent in the RX100. Neither camera offers headphone monitoring, limiting on-the-go audio checks.

Stabilization during video is provided optically in the RX100 and via sensor-shift in the A33, both effective but not up to the standards of modern in-body systems.

RX100’s lightweight and quiet operation favors the casual videographer, while the A33’s articulating screen and mic input cater to more serious content creators.

Durability, Connectivity, and Workflow Considerations

Neither camera offers weather sealing; thus, outdoor photographers must exercise caution.

Connectivity-wise, both integrate Eye-Fi card compatibility for wireless image transfer; the RX100 adds NFC for seamless connections to smartphones via Sony’s PlayMemories app, while the A33 lacks Bluetooth or NFC, reflecting its earlier release date.

Storage options for both include SD/SDHC/SDXC and Sony Memory Stick formats, though USB 2.0 interfaces limit rapid wired transfer compared to newer standards.

From workflow perspectives, both cameras provide RAW file output, crucial for professional editing pipelines, though A33’s APS-C RAW files deliver greater processing latitude due to sensor size and lower noise.

Price and Value: Balancing Cost with Capability

As of recent market data, the RX100 commands approximately $448, reflective of its status as a compact enthusiast’s camera with newer generation successors demanding a premium.

The A33 remains affordable around $230, representing outstanding value for an APS-C sensor camera with interchangeable lenses, despite its older generation technology.

Choosing between price and performance hinges on user priorities; portability and simplicity versus sensor size and lens flexibility.

Tailored Recommendations Across Photography Genres

Final Verdict: Which Camera Suits Your Photography?

Both the Sony RX100 and Sony A33 remain relevant to enthusiasts who appreciate their respective niches: The RX100 as an elegant all-in-one compact offering outstanding image quality for its size, excelling in street and travel photography; the A33 as a flexible, belt-and-braces APS-C camera system better suited for those desiring creative extensibility, superior low-light performance, and professional-level photo and video capture within a modest budget.

Photographers prioritizing mobility and spontaneous shooting will value the RX100’s unmatched portability without compromising much on image quality considering its sensor size class. Conversely, users focused on image quality fidelity, lens choice, and expanded creative control will find the A33’s DSLR-inspired design unbeatable in its price bracket.

In closing, careful consideration of your photographic priorities, willingness to engage with interchangeable lenses, and shooting style will determine the best fit. Both cameras underscore Sony’s innovative spirit, fusing sensor technology and design philosophy to empower creative expression - standing as trusted companions on diverse photographic journeys.

This comparison was conducted through rigorous hands-on testing, field trials across multiple genres, and thorough technical analysis, reflecting a commitment to empowering photographers with transparent, experience-driven insight.