This video starts talking about focus adjustment at the 15:30 mark. https://www.youtube.com/watch?v=FhK7bSw4...

I said the knob was underneath the lamp but I meant the lens, my apologies.

Excellent tutorial!!! Thanks for taking the time to post, everything is laid out for us and is super easy to follow.

Ben, I don't have actual instructions but if you take the cover off the back, underneath the lamp there is a focus adjustment knob. You can go into the Service Menu and there is a focus setting that will put a grid up where you can see the lines go from zigzag to straight when you turn the knob. If I find the video I saw it in a while back I'll post it here.