View Single Post
Old
  (#74 (permalink))
VaughnH is Offline
Lifetime Charter Member
Approaching Guru Status
 
VaughnH's Avatar
06-01-2008, 06:21 PM

Quote:
Originally Posted by wiste View Post
Comparison can be made using a Lux meter to get performance results between someone's tank in another state. When comparing light performance the in-the-water measurement might not be the way to go to get meaningful data concerning the lights being used as the water clarity would have a significant effect.

If using a light meter for comparison results how do you calibrate the meter?

Regarding the mylar being tested, was there a reflectivity rating?
Some mylar is advertised as having a 98% reflectivity and other mylar does not advertise a rating.

I got the mylar from another aquatic plant keeper, left over from a project he did, so I don't know what it was advertised to be. It is 3 mil thick, and doesn't transmit light through it, as a lot of mylar does, plus it is aluminized on both sides. All of that tells me it has high reflectance.

I have often been told on various forums, by experienced people, that mylar is not nearly as good a reflector as it seems to be. Being a skeptic I chose not to believe that. The stuff just looks so good! Compared to aluminum foil it looks like a much more efficient reflector, but that is a trick our eyes play on us. We judge a reflector by how true the reflection is, by how much it looks like a great mirror to shave by. And, that has nothing at all to do with how good the reflectance is.

I would like to say from now on I will believe what experienced people tell me.........but I'm sure I won't. Incidentally, experienced people by the dozens, also tell me that white paint is a great reflector, but with my superior knowledge I laughed that off too. Wrong again. But, I also assured a lot of people that Senator Obama could never possibly win the Democratic Presidential nomination. And, back in 1989 I assured a lot of friends that the San Francisco Giants would beat the Oakland A's in the world series. To my credit I did predict that Sacramento summers would see little or no rain.


Hoppy
  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote