couple ?'s; local MH supplier; dead pj's ballast& lens; arc lenghts;

[thedarlington]

hi everyone, i have a couple questions

1 what do you guys think of these lights would they be suitable for a projector? seem cheap but ive heard arc lenghts are an issue for projectors, so would these be an option? theyre in my city so i could ask for specifics if anyone needs more info, just tell me what, the 250w seem to really be $50, but the 400w seem to be around $20 sounds like a good deal but i dont really know

320-400W: Dyna-Brite Lighting, Inc.

250W: Dyna-Brite Lighting, Inc.



2 also, why is it that those ebay 400w mh grow lights arent recommended? what performance decrease can be expected if the arc is kinda long?

3 as a newbie light engine, i was thinking of using a 500w halogen floodlight bulb, cuz they're $1 and i was just curious why this type of system isnt recommended, i know heat & [light emmited per surface area] isnt the most optimal for a good focal point to project out, but if its like a 10-15% drop, i wont mind extra fans, would it be ok to test n get my feet wet before commiting to a MH? its only $1 after all

4 i bought a 1998 dead mitsubishi lvp-x100e , it wont turn on and it aint the fuse, but it uses MH, so i wanna try reusing that ballast, what wires would i look for to turn it on? trigger the relay?

5 finally i also removed the short throw lens, and the image appears upside down, does this mean its a duplet/triplet? any disadvantage besides an upside down lcd? i have no numbers for it but the manual said focus point between 52-62mm[zoom] do these numbers sound valid for focal calc? i think it would have to also be triplet for this to work as well btw, which i dont know just know its huge and is flat on both sides

thanks alot to all for answering =)

 

[thedarlington]

anyone at all?

 

[giorgos18]

You'll most likely want to avoid the 500w halogen - extremely high heat and not nearly as high lumen/watt ratio as metal halides.

Smaller arcs allow for less light to miss the triplet and thus make it onto your screen. A large arc will mean wasted light

Also, see if you can get the long tube and not the football style bulbs so that a reflector is easier to install.

If you can handle the heat, 400w is better than 250w in terms of brightness\

Not too sure about the ballast from the mitsubishi

I THINK that regardless of whether it's a doublet or triplet, the image will be inverted

 

[thedarlington]

thanks very knowledgeable so you wouldnt recommend the ones from the link then?

You'll most likely want to avoid the 500w halogen - extremely high heat and not nearly as high lumen/watt ratio as metal halides.

Smaller arcs allow for less light to miss the triplet and thus make it onto your screen. A large arc will mean wasted light

Also, see if you can get the long tube and not the football style bulbs so that a reflector is easier to install.

If you can handle the heat, 400w is better than 250w in terms of brightness\

Not too sure about the ballast from the mitsubishi

I THINK that regardless of whether it's a doublet or triplet, the image will be inverted