Canon 90D vs Sony A6400: An In-Depth Comparison for the Discerning Photographer

Choosing between the Canon EOS 90D, a stalwart advanced DSLR, and Sony's cutting-edge Alpha a6400 mirrorless camera isn't a trivial decision - I’ve spent weeks testing these two cameras across a gamut of conditions and genres, from studio portraits to wild, fast-paced wildlife. Both cameras, announced in 2019, target advanced enthusiasts and semi-professionals, yet their designs and capabilities reflect very different philosophies. In this comprehensive comparison, I’ll walk you through everything from sensor performance and ergonomics to autofocus and video features. By the end, you’ll have a crystal-clear idea of which camera suits your style, workflow, and photography ambitions.

Getting a Feel: Size, Handling, and Controls

Let’s start with the tangible first impressions - how they feel in your hands, and how their controls accommodate your shooting style.

The Canon 90D is a traditional, mid-size DSLR heftier at around 700 grams and larger in physical dimensions - 141mm wide, 105mm tall, and 77mm deep. Its body conveys robustness that feels reassuring, especially for those used to DSLR ergonomics. The deep grip and authoritative shutter button placement make it comfortable for prolonged handheld shooting, even with larger lenses.

Meanwhile, the Sony A6400 is a compact mirrrorless shooter designed with portability in mind. At approximately 403 grams and significantly smaller (120x67x50mm), it fits neatly in a jacket pocket or small camera bag. The grip is less pronounced, fitting smaller hands better but potentially less secure with heavy telephotos.

Looking at the control layout, the 90D boasts an abundance of physical dials and buttons on its top plate - ideal if you prefer tactile controls and quick manual exposure adjustments without diving into menus. The 11 frames per second burst rate here competes impressively with the mirrorless, accompanied by a max shutter speed of 1/8000s and an electronic shutter option reaching 1/16000s for freezing action or shooting wide-open in bright light.

The Sony A6400 strips back some physical controls but compensates with highly customizable buttons and a touchscreen interface that is often faster to navigate, especially in live view mode. It shoots at the same 11 fps burst rate but with an electronic shutter only, lacking a mechanical shutter speed that fast. This design choice benefits silent shooting and portability but with possible rolling shutter effects in some situations.

If you prize traditional DSLR handling with a future-proof built-in flash, the Canon edges the Sony slightly. But if you value travel-friendly size and touchscreen convenience, the Sony is an undoubted winner.

Sensor and Image Quality: Resolution, Dynamic Range, and ISO Performance

Both cameras sport APS-C sensors, but they differ considerably in resolution and some measured performance parameters.

The Canon 90D packs a 32.5MP sensor (6960x4640 pixels) - a notable bump from the average 20-24MP APS-C sensors. This higher pixel density delivers exceptional resolution and cropping flexibility, which I found especially useful in landscape and wildlife shooting where fine details or tight framing matters.

Conversely, the Sony A6400’s 24.2MP sensor (6000x4000 pixels) adopts a slightly larger sensor area (23.5x15.6mm vs 22.3x14.9mm on the Canon) and benefits from Sony’s advanced backside-illuminated design and excellent signal processing. DxOMark rates its color depth at 24-bit and dynamic range at 13.6 stops - impressive numbers for APS-C, especially in shadows and highlight retention.

In practical daylight shooting, both cameras perform superbly. The Canon’s resolution advantage shines in large prints and heavy cropping, but the Sony offers richer midtones and smoother tonal gradations, lending itself beautifully to portraiture where skin tone is critical.

At high ISOs, the Sony pulls ahead slightly, capable up to ISO 102400 (boosted). Its noise performance holds better detail in dim scenarios, making it a preferable choice for night, astrophotography, and indoor sports where lighting is challenging.

The 90D maxes out at ISO 25600 native and 51200 extended - solid but with a bit more noise and less refinement than the Sony at matching sensitivities.

The Viewfinder and LCD: Traditional Optical vs Modern Electronic

One major dividing line: optical pentaprism on the Canon vs. electronic viewfinder (EVF) on the Sony.

The Canon’s 0.6x pentaprism viewfinder offers 100% coverage - crisp, real-time optical clarity without lag or electronic artifacts. This remains a top preference for many DSLR users, especially in bright outdoor settings where EVFs can struggle.

The A6400’s OLED EVF delivers 2.36 million dots at 0.7x magnification, also with 100% coverage. In my testing, the EVF provides excellent resolution, with real-time exposure preview and focus peaking tools, essential for manual focusing and exposure adjustments on the fly.

Each camera has a fully articulated 3-inch touchscreen LCD, but the 90D’s screen boasts slightly higher resolution (1,040k dots vs. 922k on Sony). Canon’s articulating screen flips in all directions, great for low-angle or overhead shooting, whereas Sony’s tilts up and down - functional but more limited.

If you’re coming from a DSLR background, the Canon’s optical viewfinder will feel immediately familiar and comfortable. If you’re eager to embrace mirrorless EVF benefits like real-time exposure preview and overlays, Sony is your friend.

Autofocus Systems: Precision, Speed, and Subject Tracking

Now here’s where the Sony really sets itself apart with an enormous 425-point phase-detect AF array covering almost the entire frame, including excellent eye and animal eye detection.

The Canon 90D, meanwhile, relies on a 45-point all cross-type AF system when using the optical viewfinder and dual-pixel AF with live view. While effective, it cannot match Sony’s precision or tracking coverage.

Through extended trials in portrait and wildlife sessions, the Sony’s face and eye detection produced spot-on sharpness almost every time - particularly valuable for fast-moving pets and kids. In contrast, the Canon performed admirably but lagged behind in tracking erratic subjects or tiny animal eyes.

Sports photographers shooting fast bursts will appreciate both cameras’ 11 FPS speeds. However, in my experience, Sony’s AF keeps up better in continuous tracking modes due to its advanced algorithms and denser AF array.

Despite this, Canon enthusiasts familiar with DSLRs will appreciate the dependable AF with native Canon EF lenses, which offer fast aperture wide telephotos and amazing glass options. Sony’s E-mount lens selection has improved drastically but still lags behind Canon’s vast ecosystem, especially at the high-end telephoto and specialty lenses.

Build Quality and Weather Resistance: Durability for Rough Use

Both cameras boast some level of environmental sealing but stop short of professional weatherproof rating.

The Canon 90D’s polycarbonate body with magnesium alloy front and top plates feels solid and reassuringly built. Canon includes a built-in flash with a 12m range - useful for fill light when you want to avoid lugging heavy strobes.

The Sony A6400’s rangefinder-style mirrorless design feels more plasticky but still well-assembled. It also features weather sealing effective against dust and moisture, a boon for adventurous shooters.

Neither camera is freezeproof, shockproof, or crushproof, so for extreme adventure photography, protective cases remain advisable.

Lens Ecosystem and Compatibility: What Glass Can You Use?

Lens choices can make or break your experience, especially for genres that demand specialized optics.

Canon’s EF/EF-S mount gives access to over 320 lenses, covering budget to top-tier L-series prosumer glass. This unmatched variety lets you choose from extensive fast prime options, rugged telephotos for wildlife and sports, and macro lenses.

Sony’s E-mount system has grown rapidly, now with over 120 native lenses. Many high-quality primes and zooms are available, and third-party manufacturers like Sigma and Tamron have stepped up. However, native telephoto options underperform the Canon ecosystem in sheer numbers and aperture breadth.

Adapting older lenses is possible on both cameras but with varying degrees of AF reliability.

Battery and Storage: Shooting Duration and Buffering

If you’re planning long shoots or travel excursions, battery life is critical.

The Canon 90D offers an impressive CIPA rating of approximately 1300 shots per charge (using the viewfinder, which is typical DSLR practice). This longevity is ideal for nature photography expeditions or extended events without spare batteries.

Sony A6400 trails with about 410 shots per charge, reflecting mirrorless’s higher power draw for EVF and sensor use. Carrying multiple batteries is a must if you shoot extensively outdoors or in remote locations.

Both cameras utilize a single SD card slot, with Canon supporting faster UHS-II cards, aiding buffer clearing for the 90D’s high-resolution images, making it more efficient for burst shooting large RAW files.

Sony uses UHS-I cards and supports Memory Stick Duo as well, though UHS-II support is absent.

Video Capabilities: 4K, Frame Rates, and Stabilization

Videographers should pay close attention here.

Both cameras record 4K (3840x2160) at 30fps, but bitrate and codec differ: Canon records 120 Mbps in MP4 H.264, while the Sony uses 100 Mbps XAVC S, also MP4/H.264. Both produce excellent 4K footage, with Sony offering better dynamic range and color depth due to sensor optimization.

Neither offers in-body image stabilization (IBIS), so handheld video demands stabilized lenses or gimbals.

Canon includes both microphone and headphone ports - a boon for serious video shooters who want audio monitoring and input flexibility.

The Sony A6400 has a mic input but lacks a headphone jack, limiting soundtrack review on set.

An articulating screen helps both cameras, but Sony’s touchscreen autofocus during video is brutal in performance, especially with Real-time Eye AF.

If hybrid photo/video use is a priority, Sony’s autofocus and video quality slightly tip the scales, but Canon’s superior connectivity and slightly higher bitrate are valuable for videographers who prefer DSLR ergonomics.

Real-World Sample Images and Performance Summary

Time to see how all this tech translates into images.

Canon 90D front Canon 90D screen back Sony A6400 front Sony A6400 screen back

Looking at these sample galleries you can notice:

• The Canon 90D captures razor-sharp details due to its higher resolution sensor, especially in landscapes and portraits.
• Sony A6400 images boast superior color fidelity and smoother gradients, thanks to its advanced sensor and image processing.
• In low-light indoor shots, Sony maintains cleaner images at higher ISO values.
• Autofocus in portraits is more reliably locked on Sony’s eye and animal detection, but the Canon is no slouch.
• Both cameras manage acceptable backgrounds bokeh, but Canon’s larger zoom lens selection allows better control.

Performance Scores and Genre-Specific Analysis

Weighing overall performance and suitability across genres can help narrow the choice.

The Sony A6400 scores higher in autofocus, video, and low-light categories.

The Canon 90D excels in resolution, battery life, and handling for traditional DSLR users.

For specific photography domains:

• Portraits: Sony’s eye AF and color science make it a winner.
• Landscape: Canon’s higher MP sensor edges ahead.
• Wildlife: Canon’s lens variety and ergonomics win, but Sony's AF tracking is superb.
• Sports: Both sports equal FPS, but Sony’s AF is more refined.
• Street: Sony’s compact body and silent shutter make it ideal.
• Macro: Canon’s lens options are advantageous.
• Night/Astro: Sony’s low-light performance excels.
• Video: Sony takes the lead with superior AF and codec options.
• Travel: Sony’s size and weight are big pluses.
• Pro Work: Canon’s reliability and professional lens choices make it attractive.

So, Which Camera Should You Choose?

I often get asked: “If you could only take one, which would it be?” Honestly, it depends on your priorities.

Choose the Canon 90D if you:

• Are committed to DSLR ergonomics with extensive tactile control.
• Want the highest resolution APS-C sensor for large prints and cropping.
• Shoot mostly stills - landscapes, portraits, wildlife - where battery life and lens availability matter.
• Desire built-in flash and robust physical controls.
• Need excellent battery life for long shooting days.

Choose the Sony A6400 if you:

• Value compactness and weight savings for travel or street photography.
• Want the most advanced autofocus, especially eye and animal detection.
• Are a hybrid shooter needing strong video features and real-time exposure preview.
• Prioritize low-light performance and fast electronic shutter options.
• Prefer EVF with focus peaking and zooming aids.

Final Thoughts: Bridging DSLR and Mirrorless Worlds

Both Canon 90D and Sony A6400 reflect the camera landscape’s fascinating evolution. The 90D honors the DSLR legacy with a high-resolution sensor and familiar handling; the A6400 pushes mirrorless boundaries with autofocus sophistication and compact design.

If you’re buying today, weigh your shooting habits and lens investments carefully. Whether DSLR or mirrorless, both systems produce stunning images - your decisive factor will be how each complements your workflow and creative vision.

Happy shooting!

For an interactive deep-dive and side-by-side feature tests, check out my video review linked above.

Note: Prices quoted are approximate as of 2024.

Thank you for reading my comparison. Feel free to reach out with questions or for personalized recommendations!