Bulb/Ballast Question

ballast for Ushio retrofit lamp

Some people have used it with an electronic ballast, but not all of them work well with it. The UHI-S400DD is designed to screw right into an HPS fixture to upgrade the light quality. It really works best with an S51 HPS ballast, capacitor, and ignitor. I don't think it will work at all with an M59. I have the Ushio spec sheet, and definitely only says "S51 with ignitor".

There are other places to find an S51 ballast: These are used for those pink parking lot and street lights, so it should be easy to find one locally. Just don't confuse the people you ask by mentioning the Ushio MH lamp. Then they will think you need an MH ballast. Just say "ballast kit for 400 Watt HPS"

goodmart.com sells them for $62.49 US, but the shipping will be pretty high because the ballast is so heavy:


Try to find a local industrial lighting supplier.
Ballast info

I've been reading the forums trying to find specific ballast / bulb details, but no one has really described the differences between what is available.

Lighting should be around 5000K - 6500K?

Noise level of a magnetic ballast? Is it REALLY that much louder than an electronic?

What are the advantages of an electronic ballast?

HQI vs Mogal vs ATI vs BYOB vs AHHHH!!!!! What are all these acronyms????

Double ended vs single ended bulbs?

Arc lengths?

250W? 400W? 1000W? Wattage?? Any good rule of thumb for wattage for throw/screen size? Bigger LCD, more lumens? Do you get more light from a 250W with a good reflector / condenser than you do a 400W?

AC / DC?

I know it's a lot of questions, but I'm sure I'm not the only one who would appreciate a great explanation of these terms and suggestions for where to start looking (based on your own design). Thanks ahead of time!


2005-08-06 2:06 pm
I have also been reading threads here for the past 10 days (im very excited about starting my first projector project :D )

I have a goodmans portible DVD player with 5" screen (its a REALLY rubbish screen res, but as it cost me nothing I think its worth builing a small projector using it so I can make misstakes to learn from, so that when I have enough for a liliput 7" Il be a little pro ;)

My question is pretty much the same as above, I have searched high and low for a clear awnser but all i can see is random posts from different people sujesting differnet things.

Could someone that knows the game please explain to me (in english for n00bs :p ) The differnet types of bulbs, how to avoid a yellow picture - from what i read if you have a bulb under 4000k the pic will be to yellow.... but im a n00b and dont know what 4000k means, also this luminums (excuse my spelling if its incorrect) thing that you need a higher number of to get a clearer/brighter pic ??

To put it simply..... I wish to go to a lighting shop that is local to me and try and buy or see if the owner can order me one. As it stands im going to walk in there and say...."um...er....do you have a bright light it needs loads of luminiums and lots of K's, I dont know what im talking about and you proberbly dont either so excuse me while I stand here like a n00b.

I have been on these forums over a week now and have learned a MASSIVE amount of information, Thanks to all for your help :)