What Is the Best B Camera for the FX3?
Here’s the short answer - my choice is the FX2 and was the FX30 before they released the FX2!
When I build a two-camera setup, the FX3 is usually my primary. Its low-light chops and compact form factor make it unbeatable for run-and-gun work. But picking the right B-camera to pair alongside it can be just as crucial. You need a body that matches color science, complements the FX3’s strengths, and fills in any gaps—whether that means higher frame rates, sharper stills, or a lighter secondary rig for quick cutaways. Here’s how I choose my favorite B-cameras for every type of shoot.
What Makes a Great B-Camera?
Before we dive into models, let’s nail down the must-have features for a B-camera pairing with the FX3:
Color and Log Compatibility: Ideally S-Log3/S-Gamut3.Cine so grading is painless.
Form Factor: Lightweight enough to swap in handheld or on gimbals.
Frame-Rate Flexibility: More options for slow-mo or fast action.
Sensor Strengths: A different sweet spot—higher resolution stills or better rolling-shutter control.
Budget and Workflow: Matches your editing pipeline without doubling rental costs.
Top B-Camera Picks
1. Sony FX2
Why I Love It as a B-Cam: Same S-Log3 color, dual native ISO (800→4,000), and 33 MP stills make it a true hybrid companion.
Where It Shines: Controlled interviews, HR video packages, any time you need still-grab frames alongside your footage.
When to Choose It: You already own one FX3 and want a seamless mix plus photo backups.
2. Sony FX30
Why It’s a Contender: APS-C sensor but full access to S-Log3, 4K 120 fps, and a tiny footprint.
Where It Shines: Micro-budget shoots, drone mounting, or S-cam on a gimbal for dynamic action.
When to Choose It: You want a wildly portable second angle without sacrificing color-grade matching.
3. Sony A7S III
Why It Works: Identical 12 MP sensor size and very similar low-light profile to the FX3—so you’re bleeding-edge at ISO 12,800 without any surprises.
Where It Shines: Slow-mo up to 120 fps in 4K and excellent in-body stabilization for gimbal shots.
When to Choose It: You need extra high-frame-rate cutaways or plan to do handheld slider b-roll.
4. Sony A7 IV
Why I Reach for It: 33 MP stills, 4K 60 fps, and trustworthy autofocus—perfect for mixed photo-video days.
Where It Shines: Corporate events and lifestyle shoots where you need marketing-grade photos in addition to video.
When to Choose It: Your day includes headshots or product stills alongside your motion work.
Side-by-Side Comparison
My Go-To Recommendations
Run-and-Gun Interviews & Cutaways: FX2—matches color perfectly and gives you still-grab flexibility.
High-Frame-Rate Action & Slow-Mo: A7S III—when you need up to 120 fps without swapping codecs.
Ultra-Lightweight Second Angle: FX30—tuck it in your bag for drone or gimbal mounting.
Hybrid Photo-Video Shoots: A7 IV—one camera for polished headshots and seamless video.
Final Thoughts
Choosing the right B-camera isn’t just about specs—it’s about workflow, shoot style, and the story you’re telling. Pairing an FX3 with one of these bodies ensures you’ve got every angle covered: from cinematic low-light hero shots to crisp stills and epic slow-mo.
