Do VHO's need a reflector behind them..?

[trockafella]

Do VHO's need a reflector behind them..? Lets start there before asking anytihng else..

[jason the filter freak]

VHO's already have painted reflectors, spending money on actual reflectors... would be a waste of money

[dbartco]

VHO's already have painted reflectors, spending money on actual reflectors... would be a waste of money

 

 

SOME have internal reflectors. Some don't. Those that do usually cost just a few bucks more.

[SeanCallan]

VHO's already have painted reflectors, spending money on actual reflectors... would be a waste of money

 

Are you sure ALL VHOs have a painted reflector? I know that URI bulbs do, but I wouldn't say with certain that they all do.

 

I used to light my 75 with VHOs and I'd recommend a reflector or at least a glossy white canopy. The reflector in the URI bulbs still allowed a tad bit of light out.

 

I'd say a reflector is always a decent idea since they are relatively cheap and well...they reflect so you have much less lost light which might otherwise not be directed into the tank.

Edited November 10, 2008 by SeanCallan

[Brian Ward]

If you go with the ones that have internal reflectors then I would say you don't NEED a reflector, but you could derive some (albeit minimal) benefit by having one. Even if it's just as a heat shield. I wouldn't spend much money on something fancy, but some bent and polished aluminum wouldn't hurt.

[trockafella]

Thanks, i was just looking into a few options and thought i would get some insight on the vho's...

[lancer99]

VHO's don't need reflectors. They will light up just fine without them.

 

 

Internal reflectors on fluorescent tubes are completely useless, since all of their light output comes from the (opaque) coating on on the inner surface of the tubes.

 

External reflectors will increase their light output.

 

-R

[Coral Hind]

Internal reflectors on fluorescent tubes are completely useless, since all of their light output comes from the (opaque) coating on on the inner surface of the tubes.

 

External reflectors will increase their light output.

 

-R

 

I don't totally agree with you. You are correct that the phosphor or white coating produces most of the bulbs light output but not all. An internal reflector actually does increase the bulbs directional output greatly. The reflective coating in the bulb is between the glass and the phophor coating. So the whole inside of the bulb will flouresce but the half of the bulb with the reflector directs that light directly to the other side and out of the bulb.

 

The internal reflectors work better then external reflectors because an external reflector bounces the light right back into the bulb which causes some of the light to be blocked by the coated glass tube and the light being emiting out of it.

 

Scan from Interior Lighting for Designers, page 88

 

 

 

 

What do you all think about coating the inside of a hood with this stuff?

[SeanCallan]

What do you all think about coating the inside of a hood with this stuff?

 

Do it and post results.