Ba r r y wrote:

Lew,

Is there a formula to correct for the distance of the subject to the
fixture?

There are some, but frankly I never used them.

Good engineering and some basic SWAGs took care of things.

It seems to me that low ceilings always need more lights. Or is it my
imagination?

Your observation is correct.

Low ceilings are difficult.

When you design a work place lighting sysyem, you are trying to deliver
the light to the work surface assumed to be 36" above the floor.

The spacing between fixtures is a function of the mounting height above
the work surface and the "spread angle" of the fixture.

When it comes to lighting a workshop in a typical basement, it becomes a
"what works" situation.

A single lamp fixture located on 32" centers worked for me in my
basement shop a long time ago.

YMMV

Lew