[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Various comments on lighting

On Fri, 14 Jul 2000, Neil Frank wrote:

> >From: "James Purchase" <jpurch at interlog_com>
> >Subject: Re: Hanging pendants vs closed cover
> >It has been my experience that even a tank with nothing in it  but water and
> >gravel can be a significant light source for an entire room.  Light manages
> >to come out of it all over the place. 
> Wright: is the light coming back into the room from reflected surfaces like
> the gravel?

It's very simple: The light coming from the tank into any given point in
the room is from WHATEVER YOU CAN SEE from that particular point in the

So here's a fun thing you can do... go to different angles relative to the
tank, and note what you can see!  This was how I confirmed Wright's
original prediction about total internal reflection a few years back... I
put my head just outside (but against) the tank and looked up towards the
tank light.  Moving my had from the bottom of the aquarium up, I could
figure out just where the tank light became visible (which was, as Wright
predicted, only when I was very near the top of the tank, and very close
to the glass itself).

But the key point is, from wherever you are standing in the room, the
light escaping from the tank to that point is the same as what you can

  - Erik

PS: Off-topic.  Anyone else from this list going to the ACA convention
next week?  In past years I've traded or sold plants from my room.  Makes
a good balance to those poor folks with nothing but fish...

Erik Olson
erik at thekrib dot com