A6700 with 200-600 mm Lens Not Focusing Well with Back Button Focus Enabled
Hello Experts,
I have been using an A6700 with a 200-600 mm lens for my wildlife photography for approximately the last two years. Recently, I began utilizing back-button focus and disabled the shutter button focus.
Over the past month, I have observed a significant degradation in focusing performance. I did not encounter any issues when using the default focus button (shutter button), as it generally focused well, and overall, I was quite satisfied.
However, since switching to back-button focus, the camera's performance has been somewhat lackluster, particularly when photographing birds in challenging positions.
While I recognize that the A6700 is a powerful camera, as I have experienced over the past two years.
I am not satisfied with its performance when using back-button focus.
Per my observation the focusing system stated performing average specially on challenging situation.
During my recent trip, I noticed a lag and jitter when attempting to focus on rapidly moving subjects.
I would like to inquire if anyone else is experiencing this issue or if I may be doing something incorrectly.
I am open to reverting to the default focusing system at any time, but I am curious about this matter.
Sony Alpha India 783
Hi Rathindra,
Thanks for sharing your experience—in short, everything you've noticed adds up to reports we've seen from other A6700 users. It’s likely not a defect, but rather a settings/technique tuning issue with back button focus.
Why Back Button Focus (BBF) Feels Different
• BBF separates focus from exposure and shutter—ideal for tracking, but requires correct AF mode and customization (alphauniverse.com).
• When misconfigured, BBF can feel less responsive than half press focus, particularly with fast-moving wildlife.
What to Check & Adjust
1. AF Area + Tracking Mode
• For birds, use Tracking: Spot S or Expand Spot instead of wide/zone modes (helpguide.sony.net).
• Increase AF Tracking Sensitivity (“stickiness”) to avoid focus hunting when birds pass behind branches.
2. Assign Buttons and Focus Modes Properly
• Ensure your AF ON button is mapped to permanent AF ON, not temporarily activating only while pressed (helpguide.sony.net).
• Button-to-mode mapping: Use one button for AF ON with tracking, and configure another (like C2) for spot-focus or spot tracking .
3. EVF Refresh Rate
• Increase EVF refresh to 120 fps, minimizing viewfinder lag and improving response to fast-moving subjects (garyluhm.net).
✅ Configuration Checklist
Task Suggested Setting
Custom Key AF ON button → permanent AF ON
C2 button Set to Tracking On (e.g. Spot S tracking)
Focus Area Spot S or Expand Spot
AF Tracking Sensitivity 5 (locked-on)
EVF Refresh 120 fps
DMF Enable for quick manual adjustments
Why This Helps
These settings ensure that:
• Focus stays locked on birds through branches or on-the-move.
• No lag or jitter due to switching settings mid shot.
• You retain ability to fine tune focus manually as needed.
Summary
1. Re-map AF ON correctly for continuous focus.
2. Set Spot S + tracking with high responsiveness.
3. Turn EVF refresh to 120 fps and enable DMF.
4. Practice tracking birds in-flight with this setup.
If behavior remains inconsistent, double-check lens firmware and camera AF behavior in controlled tracking drills. Let us know how it goes—we would be happy to help further!
- June 12, 2025, 5:42 p.m.