I have read a million overly engineered threads here, but have yet to find a simple answer to a simple (stupid) question....
It's not a stupid question. The problem is that the answer MAY not be so simple, depending on a few things you DIDN'T mention....
if I have a 1 car wide, by 2 deep garage (which I use as my workshop) and I have 4 foot, two bulb, florescent lighting... should I mount them wide or long for the best lighting?
And here is the first place we need more information.
When you say you use this space as your "workshop", just what sort of work are we talking about? For example, if this is a woodshop, or a general puttering place, the answer will be quite different than it would be if it were used primarily for, say, automotive projects.
In the former case, your first priority is to evenly illuminate the ENTIRE space, particularly including the "middle" of what would otherwise be each parking bay. This implies that the lighting would be placed more-or-less directly overhead. And to get the most coverage out of each fixture, you'd PROBABLY want to place them "crossways" within the bay so that their output can bathe more of the area in front of and behind each fixture location. I'd probably also stagger them a bit, to maximize the side-to-side coverage.
But in the latter case, the LAST thing you need to light up is the middle of the cars' roofs; and the cars themselves will create giant shadows if the lighting is placed directly overhead in the center of each bay. So in this case, you'd want to run the lights "fore & aft" on BOTH sides of where the cars will be parked. This will avoid that "giant shadow" effect, and place most of the light where you REALLY need it -- at the sides of the vehicles, where you'll actually be working. It will also do a better job of illuminating any shelving, cabinets, etc. which may be placed along those side walls, as long as the fixtures are still kept at least a couple feet away from the walls themselves. Typically, you'll want to augment these "long-ways" runs with SOME additional fixtures placed "crossways", particularly at/near the ends of those runs. When properly placed, these additional fixtures both help to illuminate whatever walls they are adjacent to, and throw some additional light into open engine bays, etc.
I currently 3 four footers mounted long (or front to back) but am thinking that I may change them up to wide (side to side) and probably install a few mote.... maybe 5 total.
Regardless of the orientation, six (F32T8?) tubes to light up what is presumably about 400 ft.^2 of floor space is grossly inadequate, even if "perfectly" placed.
Tell us more about the space itself (particularly its dimensions, INCLUDING the ceiling height; and how it is finished inside; and the placement of any "major" items like workbenches, toolchests, stationary machines, etc.), and how you (primarily) use that space, and perhaps we can offer some additional (or at least more specific) suggestions.
