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Thread: Parabolic Reflectors

  1. Default Parabolic Reflectors

    Ok guys so I was in a different thread conversating the positives of hanging a CFL horizontally thus making more use of the light..and made this image to explain why it would help, especially alongside a reflector ;



    So it got me thinking about how the parabolic light/reflector works.. since we lose light each time light bounces off anything, how much light exactly are we losing and is it worth losing this efficiency at the amount of reduction in temperature we get using them?

    Does anyone have any thoughts on this?

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    Quote Originally Posted by IceCalibur View Post
    Ok guys so I was in a different thread conversating the positives of hanging a CFL horizontally thus making more use of the light..and made this image to explain why it would help, especially alongside a reflector ;



    So it got me thinking about how the parabolic light/reflector works.. since we lose light each time light bounces off anything, how much light exactly are we losing and is it worth losing this efficiency at the amount of reduction in temperature we get using them?

    Does anyone have any thoughts on this?
    You would need a Light meter to measure your PAR, there is A certain spot where all is at it's best. Go over to Google and do some reading up on the subject. JMO

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    Quote Originally Posted by hotshot View Post
    You would need a Light meter to measure your PAR, there is A certain spot where all is at it's best. Go over to Google and do some reading up on the subject. JMO
    Yeah, I've been googling this hotshot and getting similar feedback bro..seems there is a certain 'sweetspot'.

    I think I'm gonna go ahead with the parabolic anyway as I have seen good feedback on it, I was just wondering really whether it would actually be better if the lamp was horizontal in the parabolic reflector.

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    Quote Originally Posted by IceCalibur View Post
    Yeah, I've been googling this hotshot and getting similar feedback bro..seems there is a certain 'sweetspot'.

    I think I'm gonna go ahead with the parabolic anyway as I have seen good feedback on it, I was just wondering really whether it would actually be better if the lamp was horizontal in the parabolic reflector.
    I have one that is Horizontal, and I love it. I can keep my 600W MH or HPS 16" and seem's to be perfect.

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    You got a point looking at it. Seems like youre trading half the direct light for all of it being bounced once. I suppose the question would be if bouncing all of the light once results in a lower par loss than bouncing half of it however many times it takes to get it out of the horizontal hood.

    Par meter needed me thinks.

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    Quote Originally Posted by CuriousaurusRex View Post
    You got a point looking at it. Seems like youre trading half the direct light for all of it being bounced once. I suppose the question would be if bouncing all of the light once results in a lower par loss than bouncing half of it however many times it takes to get it out of the horizontal hood.

    Par meter needed me thinks.
    Yep exactly what I'm thinking CuriousaurusRex, I think I might do some tests...I can always sell the parabolic reflector if it turns out we are losing too much.

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    Quote Originally Posted by hotshot View Post
    I have one that is Horizontal, and I love it. I can keep my 600W MH or HPS 16" and seem's to be perfect.
    You have a parabolic reflector which angles the bulb horizontally bro?

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    Quote Originally Posted by IceCalibur View Post
    Yep exactly what I'm thinking CuriousaurusRex, I think I might do some tests...I can always sell the parabolic reflector if it turns out we are losing too much.
    Seems like it works off of the same principle as a newtonian telescope. If so the height of the reflector would change its f/ratio. You guys talking about a "sweet spot" is what makes me think of it. You might get some useful information from studying a bit of optics. If Im right then the reflector is doing way more than bouncing light from the bulb.

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    Quote Originally Posted by CuriousaurusRex View Post
    Seems like it works off of the same principle as a newtonian telescope. If so the height of the reflector would change its f/ratio. You guys talking about a "sweet spot" is what makes me think of it. You might get some useful information from studying a bit of optics. If Im right then the reflector is doing way more than bouncing light from the bulb.
    Hmm I'm liking the sound of that, gonna research this as much as possible, cheers CuriousaurusRex

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    Good bit of thinking here.

    Go off the spec reflection coefficient for the reflector surface for how much light is reflected.

    Bear in mind the distance travelled by the light, this is key ( parabolics makes use of this )

    CFL works for the example but imagine the light lost between each tube and within the tubes. Gash lights lol.

    It would be good to compare the bulb in same orientation, with and without reflector too.

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