250W DE halide mounted at 30 degree angle to waters surface

RicGio · 05/09/2007, 03:20 PM

I was wondering if anyone has mounted a halide fixture (in my case I'd be using a 250W DE) at an angle to the waters surface. I curious to see if it'll create an slanting effect of the rays and shimmer lines. I was thinking 20-30 degrees. I don't know if it would be a very efficient use of Par and how much would reflect back off the surface. just thought it might look kinda cool.

RicGio · 05/13/2007, 07:40 AM

Anybody?

triggerjay · 05/14/2007, 08:42 AM

Halide bulbs are mostly designed to be run in either a vertical position, or a horizontal position. Some bulb makers state this on the bulb, for example, a 400w mogul base bulb may look like this :
400W-MH-H or 400W-MH-V or 400w-MH-U
The last letter denotes the position the bulb can be run. Horizontal, Vertical, or Universal. The universal would be the only one that should be run in an odd position. Hope this helps!

Jason

Nickme23 · 05/14/2007, 09:51 AM

the angle of the bulb isn't going to have any effect on shimmer lines. Light entering the top of the water is light entering the top of the water. However if you were to install a MH bulb inside a large diameter tube and angle the tube towards the water you would basically have a spotlight effect and might change up how the shimmer lines looked but IMO it's basically an exercise in futility. No real benefit and a huge eyesore sticking out above your tank

RichConley · 05/14/2007, 11:02 AM

Quote:

Originally posted by Nickme23
the angle of the bulb isn't going to have any effect on shimmer lines. Light entering the top of the water is light entering the top of the water. However if you were to install a MH bulb inside a large diameter tube and angle the tube towards the water you would basically have a spotlight effect and might change up how the shimmer lines looked but IMO it's basically an exercise in futility. No real benefit and a huge eyesore sticking out above your tank

Reflectors have the same usage as that tube.

The problem is, theres a "critical angle" where light stops entering the water and reflecting off of it. The more you move your reflector from horizontal, the more light is going ot be past the critical angle.

RicGio · 05/14/2007, 11:16 AM

thats what I thought. Thanks for the input.

hahnmeister · 05/14/2007, 11:49 AM

Keep in mind that all light that tries to enter the water at greater than 45 degrees will be lost, as this is beyond the critical angle of the air/water boundary. So if the center of your bulb is 30 degrees tilted, and the outer edge of the light is 45 degrees, that means that all light from the reflector 15 degrees to 45 degrees will be lost. This could be a good third of your light.

05/09/2007, 03:20 PM	#1
RicGio Registered Member Join Date: Oct 2002 Location: NJ Posts: 658	250W DE halide mounted at 30 degree angle to waters surface I was wondering if anyone has mounted a halide fixture (in my case I'd be using a 250W DE) at an angle to the waters surface. I curious to see if it'll create an slanting effect of the rays and shimmer lines. I was thinking 20-30 degrees. I don't know if it would be a very efficient use of Par and how much would reflect back off the surface. just thought it might look kinda cool.

05/13/2007, 07:40 AM	#2
RicGio Registered Member Join Date: Oct 2002 Location: NJ Posts: 658	Anybody?

05/14/2007, 08:42 AM	#3
triggerjay Registered Member Join Date: Mar 2007 Location: Cape Coral FL Posts: 940	Halide bulbs are mostly designed to be run in either a vertical position, or a horizontal position. Some bulb makers state this on the bulb, for example, a 400w mogul base bulb may look like this : 400W-MH-H or 400W-MH-V or 400w-MH-U The last letter denotes the position the bulb can be run. Horizontal, Vertical, or Universal. The universal would be the only one that should be run in an odd position. Hope this helps! Jason

05/14/2007, 09:51 AM	#4
Nickme23 Registered Member Join Date: Mar 2007 Location: Northern Louisiana Posts: 28	the angle of the bulb isn't going to have any effect on shimmer lines. Light entering the top of the water is light entering the top of the water. However if you were to install a MH bulb inside a large diameter tube and angle the tube towards the water you would basically have a spotlight effect and might change up how the shimmer lines looked but IMO it's basically an exercise in futility. No real benefit and a huge eyesore sticking out above your tank

05/14/2007, 11:16 AM	#6
RicGio Registered Member Join Date: Oct 2002 Location: NJ Posts: 658	thats what I thought. Thanks for the input.

05/14/2007, 11:49 AM	#7
hahnmeister Moved On Join Date: Sep 2005 Location: Brew City, WI Posts: 10,156	Keep in mind that all light that tries to enter the water at greater than 45 degrees will be lost, as this is beyond the critical angle of the air/water boundary. So if the center of your bulb is 30 degrees tilted, and the outer edge of the light is 45 degrees, that means that all light from the reflector 15 degrees to 45 degrees will be lost. This could be a good third of your light.