As some are aware I maintain a collection of free to use e-classes and simulators, as well as my Magic Lantern and CHDK Lua scripts.
The e-classes and simulators run in the Desmos environment, a learning tool aimed at maths students and teachers.
The e-classes and simulators are all aimed at getting a deeper understanding of focusing, and cover everything from single focus, through to focus bracketing and using a tilt-shift lens.
In addition you will learn a few focusing tricks: The hyperfocal Rule of Ten and the Odds/Even rule for focus bracketing.
The only 'downside' with using Desmos is that each class/simulator is only live for a fixed period and thus I need to refresh each activity every now and then.
I'm pleased to say I've just refreshed all the links (on the right) for another year.
As usual I welcome any feedback on this post and especially any ideas to make the e-classes and simulators better.