Using used lights.

I guy I kow quit growing and I got all his supplies for next to nothing. Included was a bunch of bulbs that he said he used for a couple grows and then quit using them.

My question is would I be wasting time and bud on using these bulbs again? Do they make any kind of meter to see how much light is coming off of these?

I'm no HID bulb expert and don't even know how they really work but I would assume a bulb would shine at a constant until it burnt out.

some replace them every grow, some do 2 out of em some just use them till they die. A new bulb is always brighter and throws more lumens. HPS and MH bulbs can cost as little as $10/pc or some up to $80 or more I guess. If you can afford new ones - get/use new ones - if you can't they are better than nothing and still thow off alot of light. they make good spares at the very least in case a newer one blows for some reason.

Bulb's have a life span, where the lumens decrease Unless they have over, say 1000 hours on them, they would still work OK. Myself, after using the lamps for 2 years, I change. Unless you have the money to burn, I wouldn't worry about a light meter.

I change both my MH and HPS bulbs once a year or approximately every 4 grows.

Bro. Previously owned is the preferred nomenclature.

In regards to the post content, I'd buy new bulbs. It's not worth possibly sacrificing an optimum yield