Confused about light fixtures

[Hholly]

Is there a difference in power output in different fixtures that might fit the same sized bulbs? Like a different ballast, whatever that is? Like are there different kinds of 48" T-8 fixtures? Or as long as the bulb fits, no difference?
Thanks!

 

[jetajockey]

Some have higher quality ballasts than others, but in general it's not a huge difference. Reflector quality does make a big difference, but you typically don't see the high end stuff on anything other than t5s and newer nowadays.

 

[Hholly]

Ok, thanks.