Sony a5100 vs Sony A57: An In-Depth Comparison for Discerning Photographers

Choosing the right camera is often a balancing act between size, speed, image quality, and features tailored to your photographic style. Today, we put two noteworthy entry-level Sony cameras head-to-head: the mirrorless compact Sony a5100 and the more traditional DSLR-style Sony A57. Both were launched within a two-year window - in 2014 and 2012 respectively - but they cater to subtly different user approaches and priorities.

Having logged many hours shooting with both systems, I've found their contrasts particularly illuminating. Whether you are a hobbyist exploring serious photography, an enthusiast juggling multiple genres, or a professional looking for a versatile second body, this comparison will help clarify which camera suits your needs better. We dive deep into design, sensor performance, autofocus, and real-world shooting scenarios across diverse genres like wildlife, portraits, landscapes, and more.

Let’s start with a visual overview of size and ergonomics, as this often sets the tone for user experience.

Compact and Streamlined vs Classic DSLR Handling

Right off the bat, the physical profiles of these cameras couldn't be more different. The Sony a5100 is a rangefinder-style mirrorless camera. Its size (110x63x36 mm) and lightweight body (283g) make it highly portable - ideal for travel, street, and casual shooting. You could easily slip it into a jacket pocket or a small purse. The tilting 3-inch touchscreen with 922K dots facilitates selfie-friendly and creative angle shots.

Contrast that with the Sony A57, a compact DSLR body weighing more than twice as much at 618g and significantly larger at 132x98x81 mm. The grip is substantial, providing comfort and security especially when fitted with larger telephoto or zoom lenses. The fully articulated 3-inch screen (921K dots) lacks touch but excels in versatility, perfect for shooting at high or low angles.

A notable ergonomic advantage of the A57 lies in its extensive physical controls. From mode dials to exposure compensation, dedicated AF point selectors, and a traditional DSLR viewfinder, it fosters rapid adjustments without fumbling through touchscreen menus. The a5100’s minimalist button layout keeps things simple but might slow down power users who juggle varied settings.

Sensor Technology and Image Quality: Pixels and Processing

Both cameras employ APS-C sized CMOS sensors sized roughly 23.5x15.6 mm, lending similar potential in terms of light capture area.

However, the a5100 edges ahead here with a 24MP resolution compared to the A57’s 16MP sensor. The higher pixel count of the a5100 grants the ability to capture finer details, beneficial especially for landscape, macro, and portrait photography where clarity and crop flexibility are prized.

The a5100 also uses the Bionz X image processor, a more modern engine offering superior noise reduction and dynamic range optimization. In practical tests, I found its images exhibit greater detail retention in shadows and highlights, allowing greater flexibility with post-processing.

Dynamic range measurements from DxOMark reflect this: the A57 ranks marginally higher in dynamic range at 13.0 stops compared to the a5100’s 12.7 stops. While the difference is minor, the A57 might slightly outperform the a5100 under challenging lighting, like bright landscapes or high-contrast scenes.

Regarding color depth, the a5100 offers 23.8 bits, edging out the A57’s 23.4 bits, meaning it can render subtle color gradations a hair better. Low-light sensitivity shows a bigger gap: the a5100’s usable ISO extends confidently up to 1347 on test scores, surpassing the A57 which tops at approximately 785. This was evident when shooting indoors or at dusk; the a5100 produces cleaner images with less grain.

Autofocus Systems: Speed and Precision in the Field

Autofocus often determines how many shots you actually get. Here the cameras differ dramatically in technology and capabilities.

The Sony a5100 sports a 179-point hybrid AF system combining phase-detection with contrast-detection, active across almost the entire frame. This system excels in fast and accurate focus, particularly with moving subjects - very helpful for street photography and casual wildlife snaps.

Conversely, the A57 employs a more limited 15-point phase-detection AF, with only 3 cross-type points. While its Multi-Controller switch helps select AF points quickly, the system is less responsive tracking fast-moving subjects. Despite that, its continuous AF during burst shooting is commendable.

The mirrorless a5100’s touchscreen affords a quick tap-to-focus method, making it intuitive and quick in live view. The A57 lacks touchscreen but benefits from a bright electronic viewfinder (EVF) with 1440K dots and 100% coverage, giving precise framing and focus checks - something the a5100 sacrifices for size as it has no EVF at all.

As someone who shoots sports occasionally, I found the A57’s high burst rate of 12 frames per second (FPS) superior to the a5100’s modest 6 FPS. For wildlife and sports, this buffer allows you to capture peak action moments. But the a5100’s fluid touchscreen AF and smaller footprint offer distinct advantages for candid street and travel photography.

Build Quality, Weather Sealing, and Handling Durability

Neither the a5100 nor the A57 offers significant weather sealing - both target entry to mid-level shooters. The A57’s heftier polycarbonate body feels more rugged and substantial, giving confidence during extended outdoor use. Its deeper grip and larger controls also make it easier to handle with thick gloves or in challenging environments.

The a5100 is obviously designed with minimalism and portability in mind, trading robustness for convenience. If weather sealing or extreme durability under harsh conditions is a priority, neither camera will excel, but the A57’s frame feels comparatively more resilient.

Lens Compatibility and Ecosystem

Both cameras operate within Sony’s lens ecosystems but via different mounts. The a5100 uses the Sony E-mount, designed for mirrorless cameras with a short flange distance, allowing smaller and lighter lenses. Sony offers 121 E-mount lenses ranging from prime, macro, zoom, to premium G and GM lenses, expanding creative possibilities.

Conversely, the A57 adopts the Sony/Minolta Alpha (A-mount), inherited from traditional DSLRs and compatible with 143 lenses, including some legacy manual focus optics. The A-mount lens lineup includes many high-quality telephoto and macro lenses beneficial for wildlife and macro shooters.

In practice, the a5100’s mirrorless mount gives a slight edge in portability and emerging lens designs optimized for mirrorless advantages like image stabilization and advanced autofocus motors.

Battery Life and Storage Options

Battery life is an essential factor for many photographers, especially outdoors or on travel.

• The Sony A57 offers approximately 550 shots per charge, a respectable figure for DSLR-style bodies.
• The a5100 has a smaller battery delivering around 400 shots per charge, which is decent for a mirrorless camera but may require carrying spares for a full day of shooting.

Both cameras use Sony proprietary batteries but differ in model (NP-FM500H for A57, NP-FW50 for a5100). Both accept a single SD, SDHC, or SDXC card slot with support for Memory Stick Pro Duo - no dual slots here, so managing backups requires discipline.

Connectivity, Wireless, and Interface

Connectivity wise, the a5100 leads with built-in Wi-Fi and NFC, enabling straightforward image sharing and remote control through Sony’s PlayMemories Mobile app. This is a boon for casual shooters and social media enthusiasts.

The A57, launched two years earlier, lacks NFC and Wi-Fi but supports Eye-Fi card connection, an older method of wireless transfer. In modern contexts, this is less seamless compared to native wireless functionality.

Both cameras offer HDMI output and USB 2.0 connectivity for tethering or file transfers, though the a5100’s lack of microphone and headphone jacks limits video monitoring options.

Video Recording Capabilities

Videographers will find the a5100 more modern with Full HD 1080p at 60p, 60i, and 24p frame rates and slow-motion 720p at 120 fps. It supports XAVC S codec, providing better compression and quality than the older MPEG-4 or AVCHD systems.

The A57 shoots 1080p at 60p and 24p, but with older compression (MPEG-4, AVCHD, and H.264) and lacks progressive enhancement.

Neither camera offers 4K video, external mic inputs on the a5100, or headphone jacks, but the A57 does have a microphone port, affording more audio control at least.

Expect no in-body image stabilization on the a5100, whereas the A57 features sensor-shift stabilization, beneficial in hand-held video or low-light stills.

Real-World Photography Performance Across Genres

Let’s bring these specs to life by comparing hands-on experiences across photography styles.

Portrait Photography

The a5100’s higher resolution and advanced autofocus shine here. Its 180-point focal plane phase-detect AF combined with contrast AF enables fast eye detection and sharp focus on faces outdoors or in dim settings. Skin tones appear natural once white balance is tweaked from its automatic settings.

The A57’s lower resolution sensor limits cropping flexibility but delivers images with pleasing color depth. The stouter build and optical viewfinder can help frame portraits intuitively. However, slower AF speed may frustrate when shooting quick gestures or candid moments.

Both produce soft, pleasant bokeh when paired with fast prime lenses, but the a5100’s mirrorless design allows greater selection of compact fast lenses.

Landscape Photography

Here, the A57’s slightly better dynamic range (13.0 vs 12.7 stops) and sensor stabilization provide a marginal edge in capturing expansive scenes with high contrast between sky and land. The articulated screen helps compose shots from tricky angles like rocky cliffs or low water levels.

The a5100’s sharper 24MP images and live histogram aid detailed exposures but lack sensor stabilization, so little hand shake might affect slow shutter shots unless tripod mounted.

Weather sealing is absent on both, so caution is warranted during outdoor shoots.

Wildlife and Sports Photography

The A57 excels with 12 FPS burst and a sturdy grip that supports super-telephoto lenses well. Its phase-detection AF, though sparser, tracks moving animals or athletes reasonably well - perfect for beginners stepping into action photography.

The a5100’s smaller body and slower burst rate limit continuous shooting, but the hybrid autofocus is surprisingly nimble locking onto moving subjects. For casual wildlife or street action, it delivers with the advantage of stealthy operation.

Street and Travel Photography

In this arena, the a5100’s diminutive size, responsive touchscreen AF, and lighter weight make it a clear favorite. Being less conspicuous enables natural street candid shots. Its built-in Wi-Fi and NFC simplify on-the-go backup or sharing.

The A57 is undeniably more cumbersome and conspicuous, risking missed moments. Although, the sturdier controls benefit those who prefer manual shooting with gloves or difficult lighting.

Macro Photography

Both cameras depend on lens choice here rather than body specs. However, the A57’s sensor-shift stabilization gives an advantage for hand-held macro imaging to reduce vibrations. The a5100, on the other hand, benefits from more contemporary lens options optimized for mirrorless systems that often include optical stabilization.

Night and Astro Photography

The a5100’s higher ISO ceiling and newer image processor provide less noise and more detail in dark conditions - even without sensor stabilization. For astrophotographers on a budget, the less bulky setup is easier to mount on tripods.

The A57, with sensor shift stabilization and longer battery life, also performs admirably but noisier high ISO images may require careful noise reduction.

Video Production

Although neither camera is a video powerhouse by 2024 standards, the a5100 is the preferable choice due to better codec support and 1080p at 60fps. Its lack of mic input is a drawback for those seeking higher audio quality.

The A57, with a microphone port and sensor stabilization, suits run-and-gun shooters wanting more hands-on audio control but sacrifices codec flexibility.

Comparative Scorecards and Genre Ratings

To place these observations in perspective, here are consolidated DxOMark scores and genre-specific ratings.

This data affirms the a5100’s advantage in sharpness, resolution, and autofocus sophistication, while the A57 retains strong points in burst speed, dynamic range, and battery life.

Final Recommendations: Who Should Buy Which?

Get the Sony a5100 if:

• You prioritize compactness and portability without sacrificing image quality.
• You shoot a variety of genres, especially portraits, street, travel, and video.
• You value touchscreen AF simplicity and wireless sharing.
• You prefer high-resolution stills and modern processing.
• Your budget is under $500, making it an excellent entry-level mirrorless choice.

Opt for the Sony A57 if:

• You want a DSLR-like handling experience with full-sized grips and physical controls.
• Continuous shooting speed and burst buffer size matter, such as for sports or wildlife.
• Longer battery life and sensor stabilization appeal to your shooting style.
• You have legacy Sony A-mount lenses or want a wider variety of optical stabilization options.
• You can stretch to the higher price point and prefer an electronic viewfinder.

Conclusion: A Tale of Two Cameras with Different Strengths

The Sony a5100 and A57 thus sit at adjacent but distinct points in the photographic landscape. The a5100 embraces mirrorless advancements - resolution, AF responsiveness, portability, and wireless connectivity - packaged into a sleek compact body. The A57 preserves the bulk and control familiarity of DSLRs with strengths in handling, burst shooting, and sensor stabilization.

Having personally tested both in studio settings and out in the field, I can attest each has merits aligned with particular photographic ambitions. The a5100 is perfect for photographers seeking flexible, modern features in a pocketable form. The A57 suits those who value tactile controls and high-speed shooting in a traditional DSLR shell.

Whichever path you choose, you gain a dependable APS-C system from Sony capable of delivering quality imagery and enjoyable shooting experiences.

Sony a5100 front Sony a5100 screen back Sony A57 front Sony A57 screen back

Here's to making informed choices that enhance your photography journey.

Summary Table

If you have further questions or want deeper insights into lenses or post-processing for these cameras, feel free to ask - after all, the devil is often in the photographic details.