Shop lighting questions

I was at Lowes today looking for some shop lights to put up before I bring my next project into the shop. The guy in electrical told me that there are two different kinds of ballasts. The T8 is an electronic ballast and the older T12 is an obsolete balast that uses more electricity. To add more questions he also told me that the T12 that is 40 watts will produce less light than the T8 at 32 watts. I thought wattage was a measure of light output. Is this just a ploy to get me to buy a fixture that costs twice as much? For even more confusion I have two different types of bulb.
Fat ones that are 34 watt and skinny ones that are 32 watt. These were salvaged during a remodel at work when it was decided to use a different colour of bulb. Does anyone have any idea what I am talking about? I sure as hell dont. Any on-line resources?

wattage is a method of measuring energy.. wether it be light or mechanial.. a digital ballest is more efficent and will rob the tubes of less energy due to putting out less heat.

The T refers to the bulb size in eighths of an inch. The old style T12 is 12/8 or 1 1/2" in diameter, a T8 is 8/8 or 1" in diameter. T8 lamps use electronic ballasts, the older T12 could be had with either magnetic or electronic. T8 lamps will generally have a higher output in lumens; watts is the amount of electrical energy they consume.

If it matters to you, the electronic ballasts will also work in much lower temperatures than the magnetic ballasts. I've been out in my shop on -20c days and the lights fire right up. With my old ballasts I used to have to wait until the heater brought the shop up above freezing before the fluorescents would come on.

yep, the T8s are very nice, and usually very cheap thanks to china's lack of environmental controls. the 48" two-tube fixtures are usually very cheap at the lowes depot.

t5's with a good reflector are good too.

I recently installed three 4-foot T8 fixtures in my garage, replacing the lone 100 watt incandescent bulb. I bought the upgraded bulbs, which I've read make a real difference.

My wife thinks the garage is too bright now. I'd still like to get two more fixtures, but this was a tremendous improvement, so it will do.