How to get a larger AF area on Canon 5d Mark IV so all AF points are in used? (similar to the 6dii)

[alyssal]

I have googled, and tried YouTube for this, but maybe I'm asking the question wrong as I'm not finding an answer that works. My 5d Mark IV works great with my 35mm. BUT, paired with my 85mm 1.8, it is horrible at getting area in focus. For example, my 6dii works great with the 85mm and always gets faces in focus. If I'm shooting a family of four, and they all have their faces together or at the same distance, they're all in focus. With my 5d Mark IV, dad's sweater or sister's hair tends to be super sharp, and then the rest fuzzed. I've tried numerous different ways with this lens, but it doesn't like my 5d Mark iv. I'm wondering, is there a way, similar to the 6dii to set up the AF points. When I shoot on the 6dii, a larger area is what I can focus on. When I shoot on the 5d iv, even if I shoot in zone, only 2-3 AF points will still blink/activate. I'm wanting all AF points in a zone area to be activated - not just 2-4 random ones. What am I doing wrong here? I just want to activate a large zone area, but I want all points to catch focus, is that possible? Thanks!

[Waddizzle]

Welcome to the forum..  Sorry to hear you are having issues with your gear.

Many issues are caused by the gear.  Many issues are caused by the user, the camera operator.  Many issues are caused by a combination of both, when the user takes corrective action that does not correct the camera issues. 

Are you able to post images that demonstrate your issue?  Verbal descriptions of issues are subjective.  An actual sample image allows the opportunity to form objective opinions.  It is the closest we can get to “hands on” with your gear across the World Wide Web.  We do not know what camera settings you are using, for example.

I suspect that you are conflating available AF points with active AF points.  The concepts are described in detail in the User Guide.  Search for “Lens Groups””.

If you have not already done so, please download the User Guide for the EOS 5D mark IV.

https://www.usa.canon.com/support/p/eos-5d-mark-iv 

Here is a link to the 6D Mark II product support page, where you can download that User Guide.

https://www.usa.canon.com/support/p/eos-6d-mark-ii 

The cameras are able to display available AF points, active AF points, or both at the same time.  This is where “Lens Groups” enters the picture.  Different lenses allow the camera to not only have different combinations of active AF points, but also different combinations of AF point types.  You are able to control which AF points are active be selecting AF points/zones in the camera.

The 5D4 and 6D2 have very different AF point systems.  Each has its advantage over the other, depending upon lens selection and available AF point selection.  

This is further complicated by camera settings that determine how available and active AF points are displayed.  THIS is where I think your confusion begins to break down.

To resolve your issue, we need to know your camera display settings.  One quick and dirty way to control or predict your camera settings is to reset the camera body to factory defaults.  Before you do a camera reset, I’d suggest that you register your current settings in a Custom Control Mode.