It sounds like you're dealing with a frustrating focus issue with your Canon R5 Mark II, especially considering you're using some high-quality lenses like the EF 500 f/4 II and RF 100-500. Since you've already done a factory reset and tried both One Shot and Servo modes, let's break it down to a few possible causes and solutions:
1. Autofocus Mode Settings:
Servo vs. One-Shot: It’s good you’ve already tested both. Since you're mainly using Servo, it’s important to ensure you’re using the correct AF configuration for your shooting situation.
AF Points & Tracking Mode: Try adjusting the AF area mode. For wildlife photography, tracking subjects with Animal Eye AF or AI Servo in conjunction with Tracking AF can give you more consistent results. You can fine-tune this in the camera settings under AF Settings.
Tracking will help the camera stay locked on to moving subjects.
If you're shooting static subjects, Single Point AF or Spot AF could be more precise.
2. AF Sensitivity & Calibration:
Micro-adjustment: Your lenses may need to be calibrated. Even though Canon lenses are designed to focus precisely, sometimes a slight miscalibration can affect sharpness. It might help to fine-tune the autofocus settings for each lens.
AF Settings in the menu: Double-check your AF sensitivity settings. If you have it set too aggressively, the camera might focus too quickly without locking accurately. You may want to reduce it slightly.
3. Lens-Specific Focus Issues:
Since you're using a mix of EF and RF lenses, make sure the camera is set up correctly for each lens. Sometimes, even with adapters, autofocus can behave differently.
Test each lens separately and see if the issue persists across both. If only one lens is causing problems, it could be related to that particular lens rather than the camera.
4. AF Drive Speed Settings:
5. Firmware Update:
6. Test with Manual Focus:
Try manually focusing on the subject using the focus peaking feature (if available). This can help you rule out any camera-specific autofocus problems.
You can also use live view with magnification to test the focus.
7. Environmental Factors:
You mentioned you're using a tripod, which rules out camera shake, but if you’re shooting in low light, or in low-contrast environments (e.g., wildlife shots in dense trees or grass), autofocus can struggle. Ensure there’s enough contrast for the autofocus to latch onto.
8. Shooting Technique:
For long lenses like the EF 500 f/4 II, small focus errors are more noticeable. A slightly higher ISO or shutter speed (faster than 1/500s) might help mitigate focus blur due to even slight movements, especially with long focal lengths.
Recommendations:
Try a different autofocus point: Switch to a smaller AF area (like single point or spot AF), and make sure you're selecting the correct focus point.
Test with simpler subjects: Set up some static subjects to see if autofocus is consistently inaccurate or only in dynamic, real-world conditions.
Check if the issue is lens-specific: See if the issue persists on one lens versus the other. That might help narrow down the problem.
Lastly, don’t stress too much about your Yellowstone trip. You can always shoot in manual focus mode as a backup if autofocus still isn’t performing the way you want, but I’m hopeful some of these tweaks will help.
If you’d like to share more about specific settings you're using or send over a few example images, I can offer more targeted advice. I’d also recommend reaching out to Canon support if the problem persists after trying these solutions—they might have more insight or a fix tailored for the R5 Mark II.
