Sony a5100 vs. Sony RX1R II: Two Cameras, Two Worlds – Which One Fits Your Photography Style?

Choosing a camera these days often feels like standing at the edge of a vast forest trying to pick the best path without a map. The Sony a5100 and Sony RX1R II are two very different cameras from the same brand, released within a year of each other, yet aimed at distinct types of users and photographic ambitions. Over many years of testing, these two models have taught me volumes about how features, sensor technology, and handling create vastly different user experiences - and how important it is to match the camera to your needs (and wallet).

Let's embark on a comprehensive journey comparing the Sony a5100, a spunky entry-level mirrorless darling, and the Sony RX1R II, a jaw-dropping large sensor compact with premium chops. Through this comparison, I’ll share detailed technical knowledge, hands-on impressions, and practical advice based on intensive real-world testing and analysis. Whether you’re a passionate hobbyist, a pro seeking a compact backup, or simply nerding out on camera tech, this guide is for you.

First Impressions: Size, Ergonomics, and Control

At a glance, the Sony a5100 and Sony RX1R II couldn’t be more different in size and body type. The a5100 wears its mirrorless badge proudly in a rangefinder-style compact with a pop-up flash and tilting touchscreen, while the RX1R II is a pocketable wonder with an integrated fixed 35mm f/2 lens and a bright electronic viewfinder (EVF).

Weighing just 283 grams and measuring 110x63x36 mm, the a5100 feels like a nimble street ninja - light and easy to carry all day. It's notably smaller and thinner, making it a compelling choice for travel or casual shooting. The RX1R II tips the scales at 507 grams and has a chunkier profile (113x65x72 mm) thanks to its full-frame sensor and premium fixed lens. Don't let the "compact" tag fool you - this is still a substantive piece of kit that demands respect and a decent hand to hold comfortably for extended periods.

From ergonomic testing, I found that the a5100’s minimal grip can feel a bit cramped if your hands are large or you use substantial lenses. The RX1R II, by virtue of its dedicated grip and robust build, inspires confidence and stability - key traits when working in demanding conditions or with slower shutter speeds.

Both cameras sport tilting 3-inch LCD screens, although the RX1R II’s 1,229k-dot screen edges out the a5100’s 922k resolution for visibility and detail. That said - the a5100’s touchscreen capability delivers a smoother, more intuitive navigation and focusing experience, a big bonus for novice to intermediate shooters.

Sony’s thoughtful control layout shines on the RX1R II with easily accessible dials and custom buttons suitable for quick adjustments on the fly. The a5100, lean on external controls, lets touchscreen interaction dominate - functional but less tactile for the speed demon photographer.

Sensor Technology & Image Quality: APS-C vs. Full Frame

This section separates the grown-ups from the kids. The a5100 packs a 24 MP APS-C CMOS sensor (23.5x15.6 mm), while the RX1R II boasts a staggering 42 MP full-frame BSI-CMOS sensor (35.9x24 mm) without an anti-aliasing filter, designed for razor-sharp detail and maximum resolution. This critical sensor difference shapes image quality, low-light performance, and overall creative latitude.

From DXOMark benchmarks and hands-on shooting, the RX1R II scores an overall 97, dwarfing the a5100’s solid but entry-level 80. Color depth, dynamic range, and low-light ISO performance all show marked superiority on the RX1R II. For instance, the RX1’s impressive dynamic range of 13.9 EVs allows preservation of highlight and shadow detail that the a5100’s 12.7 EV struggles to hold, especially in tricky light.

This means the RX1R II is a dream for landscape photographers and those craving exquisite fine detail - HDR and shadow recovery reign supreme here. The a5100, on the other hand, while capable and versatile, will show its limits under extreme contrast or higher ISO settings, yielding more noise and less latitude.

The lack of an AA filter on the RX1R II lets it capture those microtextures and intricate patterns that the a5100 can only hint at. If you print large or crop aggressively, the RX1R II’s resolution advantage is a game-changer.

However, image quality isn't the whole story - lens quality and workflow matter greatly, too, and we'll touch on that shortly.

Autofocus and Speed: Where Entry-Level Meets Precision Engineering

Autofocus (AF) prowess is often a dealbreaker, especially for action, wildlife, or candid photography. The a5100 offers an impressively fast hybrid AF system for its class, combining 179 phase-detect points with contrast detection. Its 6 fps burst shooting is decent, enough for capturing fleeting moments in everyday use. Touch autofocus on the screen adds a user-friendly flair, especially for beginners and vloggers.

By contrast, the RX1R II’s AF system is more conservative, featuring 25 AF points without continuous AF burst mode (5 fps max, AF-S only). It employs a hybrid system with contrast and phase detection but lacks the tracking accuracy of modern mirrorless beasts. While its precision and face detection is reliable for static or slowly moving subjects, aggressive tracking in sports or wildlife scenarios is not its forte.

In practical tests, I found the a5100 more responsive for on-the-move subjects such as street photography or fast-paced events. The RX1R II demands patience and precision focusing - more of a system for deliberate, contemplative shooting. So, if you love chasing split-second action, the a5100’s autofocus feels more forgiving and flexible.

Build Quality and Weather Resistance: Crafting Cameras That Last

Both cameras skip extensive weather sealing, leaving them vulnerable to dust and moisture - a bit disappointing for serious outdoor shooters who want gear that stays reliable under all conditions. Sony, to their credit, builds a solid, well-machined body for the RX1R II, using premium materials that inspire confidence. Its weightiness feels like quality in hand. The a5100, being lighter plastic, feels less rugged but still up to the task for everyday shooting.

Neither camera claims shockproofing, waterproofing, or freeze resistance, so care is advised for extreme environments, though gently handled, they’ll keep ticking with regular use.

Handling and User Interface: Making Photography Intuitive (or Not)

The a5100's touchscreen shines for quick menu access, touch-to-focus, and image review - features that tend to get novices shooting faster and more confidently. Its simpler control scheme is a double-edged sword: great for beginners, limited for pros who crave custom buttons and dials for rapid control.

The RX1R II's lack of touchscreen means all functions rely on buttons and physical dials - a more traditional DSLR-style approach that I found liberating for quick adjustments without looking away from the viewfinder. Speaking of which…

The RX1R II’s integrated EVF (2.36 million dots, 0.74x magnification) provides a clear, immersive view - a luxury the a5100 surrenders completely. Sony’s omission of an electronic or optical viewfinder on the a5100 nudges you to rely solely on the LCD, which can be challenging in bright daylight.

This difference highly influences shooting style: the RX1R II encourages eye-to-viewfinder discipline, stabilizing compositions and reducing arm fatigue, whereas the a5100 favors casual, freestyle shooting.

Lens Ecosystem and Compatibility: How Much Glass Do You Need?

The a5100 uses the Sony E-mount, opening doors to an extensive lens library - over 120 lenses ranging from affordable primes to high-end zooms. This flexibility is gold for anyone who enjoys tinkering with focal lengths, apertures, or specialized optics such as macro or telephoto. You can build an entire optical arsenal around the a5100’s capable APS-C sensor.

The RX1R II’s fixed 35mm f/2 Zeiss Sonnar lens, on the other hand, means no swapping or upgrades. But - and this is a big but - that single optic is superb, with exceptional sharpness, minimal distortion, and the coveted Zeiss character that many photographers crave. It’s a “one lens to rule them all” approach that demands commitment but rewards with consistency and high optical quality.

For landscape, street, and portraits, 35mm is a versatile classic, but wildlife or sports shooters likely will find the RX1R II limiting.

Battery Life and Storage: Shooting Through the Day (or Not)

Battery life is where the a5100 shines relative to its size and class. Rated for around 400 shots per charge with the NP-FW50 battery, it comfortably outlasts the RX1R II’s roughly 220-shot endurance (NP-BX1). In my tests, continuous shooting sessions favored the a5100 for all-day reliability without frequent battery swaps.

Both cameras accept SD and Memory Stick cards (boring but stable), with a single card slot - nothing surprising here. USB 2.0 is a shared data interface, which feels a little antiquated compared to newer USB-C standards, but gets the job done.

Connectivity and Wireless Features: Sharing Made Simple (or Complicated)

Both cameras include built-in Wi-Fi and NFC, enabling wireless image transfer and remote camera control through Sony’s apps. However, no Bluetooth is present on either model, a bit unusual given current trends toward seamless always-on connections.

This means quick smartphone transfers are possible, but tethering or geotagging will require a bit more fiddling or third-party solutions. HDMI output lets you hook up to external monitors or recorders, with the RX1R II adding a microphone port, making it the more versatile video package (more on that next).

Video Performance: Not the Primary Focus but Worth Considering

Neither camera pursues video excellence head-on, but they perform respectably for hybrid shooters.

The a5100 shoots Full HD 60p video with decent autofocus performance thanks to its hybrid AF system - a boon for casual videographers or vloggers seeking smooth focus transitions with minimal hunting. Slow-motion capture at 120 fps in 720p is a fun added feature.

The RX1R II offers Full HD up to 60p and features XAVC S and AVCHD codecs for higher bitrates and quality. Its addition of a 3.5mm microphone input is a critical advantage for those serious about audio capture - a detail often overlooked but important for professional use. Lack of in-body stabilisation is a shared limitation, so expect shaky handheld footage unless you pair with a gimbal or lens stabilization.

Putting It to Work: Genre-Specific Performance Across Photography Disciplines

How do these cameras perform in various genres of photography? Let’s break it down:

Portrait Photography

RX1R II shines with high resolution and full-frame sensor for creamy bokeh, excellent skin tone rendition, and exquisite eye-detection autofocus. The fast f/2 lens combination renders softly blurred backgrounds that flatter subjects beautifully. Ideal for headshots or fine art portraiture where detail and tonal nuance matter.

a5100 offers respectable portrait results but with less shallow depth of field and smaller sensor limitations. Its 179-point AF catches faces easily, though bokeh is less pronounced. Great for casual or travel portraits.

Landscape Photography

RX1R II dominates with its wider dynamic range, enhanced resolution, and sharp lens. Despite lack of weather sealing, careful landscape shooters will appreciate the image quality and tonal latitude. The compact body is convenient for day hikes.

a5100 performs well in good light but shows noise and dynamic range limits in shadows and skies. Good budget option for beginners exploring landscapes.

Wildlife Photography

Neither camera is designed as a wildlife specialist, but...

a5100’s speedy and responsive autofocus with higher burst rate (6 fps) offer an edge for casual animal photography.

RX1R II's slower AF and fixed 35mm lens limit telephoto reach and focusing speed, making it less suitable for wildlife.

Sports Photography

The a5100’s 6 fps burst and hybrid AF provide usable performance for moderate action sports and amateur event shooting. RX1R II’s slower 5 fps, AF-S only mode, and limited autofocus tracking make it a poor fit here.

Street Photography

Both cameras have virtues:

a5100 is stealthy and lightweight but without a viewfinder, you might struggle under bright sun.

RX1R II has EVF and superb image quality for fine detail in urban scenes but is larger and heavier, making it less covert.

Macro Photography

a5100’s lens options make close-up shooting possible with macro lenses; RX1R II has relatively close focusing down to 14 cm with its fixed lens, good but not specialist level.

Night and Astrophotography

RX1R II’s superior high ISO performance and dynamic range make it ideal for starry skies and low light. a5100 can handle casual night shots but will show noise and limited highlight retention.

Video Capabilities

As discussed, a5100 is more beginner-friendly with touch AF in video. RX1R II impresses with better codecs and mic input, better suited for creators seeking higher quality content.

Travel Photography

a5100’s size, weight, and lens versatility fit travel needs well. RX1R II offers premium image quality in a large compact, ideal for quality-focused travelers wanting one-lens simplicity.

Professional Work

RX1R II edges ahead with full-frame resolution, robust build, and superior image quality. Lack of weather sealing and slow AF can be limitations in fast-paced pro environments but outstanding for studio, portrait, and landscape pros. a5100 serves entry-level professionals or enthusiasts on a budget.

Sony a5100 front Sony a5100 screen back Sony RX1R II front Sony RX1R II screen back

Performance Ratings Synthesis: The Numbers Behind the Narrative

Putting the numeric scores side by side confirms the qualitative impressions. Here’s a snapshot from DXOMark:

And looking closer at genre-specific strengths:

These confirm the RX1R II is a high-end image quality performer, while the a5100 delivers good all-round functionality for beginners and casual pros.

Price vs Performance: What Are You Getting for Your Money?

A vital consideration. The a5100 retails around $450 new, offering an entry into Sony’s excellent E-mount system, great sensor performance for the price, and a highly portable form factor.

The RX1R II carries a hefty $3300+ price tag reflecting its cutting-edge sensor, premium Zeiss lens, and sophisticated build. It targets a niche of enthusiasts and pros who prioritize image quality, compactness, and quality lens optics over versatility or speed.

When you compare the two, the RX1R II’s four-figure premium offers tangible gains, but these come with trade-offs: less autofocus speed, fixed lens, shorter battery life. The a5100 provides more versatility and user-friendly features at a price accessible to entry-level or budget-conscious buyers.

Final Verdict: Which Camera Should You Choose?

No camera is perfect for all situations, so I’ll break down recommendations based on user needs.

• If you are a photography enthusiast or beginner seeking an affordable, lightweight, versatile camera that grows with you through use of varied lenses, and offers solid AF and usability, the Sony a5100 is an excellent pick. It’s a great street, travel, and casual portraits camera with the benefit of touchscreen operation.

• If you are a professional or serious enthusiast prioritizing uncompromising image quality, full-frame performance, and a premium fixed 35mm lens for portraits, landscapes, and fine art, the Sony RX1R II shines. Despite its hefty price and some operational compromises (like slower AF), it delivers one of the finest image quality experiences in a compact form factor.

• For videographers dabbling in hybrid shooting, the a5100 is friendlier to focus on the fly, but the RX1R II offers superior audio connectivity for higher production value.

• If portability and silent, stealthy operation are key for your street or travel shooting, the a5100 edges out with its smaller size and lighter weight.

• If you crave the ultimate in detail, low light, and dynamic range, and budget is no object, RX1R II is the dream camera.

The Bottom Line: Trusting Your Own Journey

Having extensively tested both cameras across varied shoots, I can attest no amount of specs replaces understanding your own photographic priorities. The a5100 is a trustworthy and capable introduction to mirrorless photography, especially for those valuing ease and flexibility. The RX1R II represents a pinnacle of compact full-frame technology, designed for photographers who crave supreme image fidelity and lens excellence in a no-compromises package.

Both cameras possess virtues and limitations, but each claims a unique place beloved by many in the photography community. So after years of judgment and critique, I suggest you consider not only your genre and skill level but also the love you want to have with your camera - because a camera is a partner, not just a tool.

Feel free to reach out if you want specific lens recommendations, workflow tips, or shooting advice for either camera. Happy shooting!

Article images used:

Sony a5100 front Sony a5100 screen back Sony RX1R II front Sony RX1R II screen back