Canon Knowledge Base Lacking In 7D MarkII AF Topics

[digiquisitive]

I have reviewed all of the articles available (that I know of) on the CDLC Knowledge Base, pertaining to specifics and details as to how the predictive autofocus capabilities on the 7D MarkII work and can be used effectively.  I find a lot of Canon articles and guides on AF as they relate specifically to the EOS 1-DX and 5D MarkIII, dating back to 2012.  I understand the 7D MarkII's AF capabilities build on those technologies, so would like to have the same kind of information specifically for the 7D-II because there are differences in this newer AF system.  The newest material I see is from Rudy Windston, dated 9-15-2014 (Differences between Zone AF and AF Point Expansion).  I have reviewed various printed Canon materials many times (Instruction Manual, current version; EOS 7D Mark II AF-Setting Guidebook), Canon FAQs,and all available videos from CDLC and other sources (The-Digital-Picture.com, an excellent source) as well as David Busch's superb EOS 7D MarkII Fast Track Guide. Ideas/helps welcome.

[jrhoffman75]

I assume you know this, but:

1. A camera can only focus at one distance at a time

2. The Canon AF system selects the focus point based on the closest item covered by a focus point with sufficient contrast to activate the phase detection system.

3. AF Expansion starts with the selected focus point first and then looks to the expansion points if the primary point cannot achieve focus.

4. Zone AF has no preferential focus point and will simply select the point that latches on the closest subject with sufficient contrast using any of the focus points in the zone.

[Waddizzle]

Zone AF does not have to select it’s starting point.  

You can select a starting AF point for Zone AF Tracking when in AI Servo mode.

[jrhoffman75]

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@Waddizzle wrote:

Zone AF does not have to select it’s starting point.  

Exactly. As I said above, but explained in more detail:

https://support.usa.canon.com/kb/index?page=content&id=ART133839

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