OT (somewhat) - Tank mirrors

[Newbie Bill]

Yes this is only related to a tangent subject, but it seems most things the
group in toto, is just short of the Encyclopedia Britannica's in overall
knowledge:) Originally started on this idea as a hospital or isolation
tank, but like ponding one thing grew to another and now we have a used 50
gallon tank Sorry I cant be more specific but it seems to have mirrors on
the inside of all four sides. If you look through parallel sides you can
see through as if there is nothing there. Look at a distance through
perpendicular sides and it appears to be a strong mirror on the far side ie
you look through one, the other is a mirror. If you get close and look
through perpendicular sides the 'occupants' seem reflected but objects at a
distance, (ecspecially when back lit) are quite visible, though 'filtered'.
Put your hand right behind the glass and it is barely discernable, if at
all. I was really bummed at first, because I thought this meant the fish
would be unable to interact with us, however now it is apparent they can see
us to some degree? Walk up and they will swim towards you. Put your finger
on the glass and they dont seem to see it.

Could someone give me a short remedial course in 2 way mirrors so we can
understand how well the fish are seeing us and under what circumstances?
No, I'm not willing to stick my head in the water to see for myself :)
Thanxx
Bill Brister

[Philip Lewis]

It's been a while since physics, but the corner to corner mirror
effect is caused by the index of refraction.

You're essentially looking at the corner of a prism. (One of my take
produces rainbow on occation.... you can also see the makeup colors of
the lighting... it's simple spectroscopy)

The fish should be able to see out of the tank in all directions.
They are always looking orthogonally, and never have a light path
which is air->(glass)->water->(glass)->air like we have when looking
at the tank from certain angles.

They always have water->(glass)-> air.


of course, I could be talking out of my butt....
I'm sure someone will correct me if i've misremembered.

--
be safe.
flip
Ich habe keine Ahnung was das bedeutet, oder vielleicht doch?
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[Newbie Bill]

Thanxx - I knew someone would have an educated explanation. Plus I got to
find out what orthogonally meant:) Ive never heard that word. I definitely
dont want to take your metaphor too far but I suspect your butt speaks
pretty well. I just thought it was incidental, but there is the light
seperation thing going on, particularly when the sunlight is 'behind' it.
The only thing that doesnt ring 100% is the touching the glass. Perhaps
they just dont have that conditioned response yet but, as I mentioned they
do seem to see you outside the tank regardless of side; they dont seem to
react if you touch the glass and/or move your finger around, as I have seen
fish in clear tanks do.
Vielen Dank. Ich glaube du bis richtig:)
Bill

"Philip Lewis" > wrote in message
du...
> It's been a while since physics, but the corner to corner mirror
> effect is caused by the index of refraction.
>
> You're essentially looking at the corner of a prism. (One of my take
> produces rainbow on occation.... you can also see the makeup colors of
> the lighting... it's simple spectroscopy)
>
> The fish should be able to see out of the tank in all directions.
> They are always looking orthogonally, and never have a light path
> which is air->(glass)->water->(glass)->air like we have when looking
> at the tank from certain angles.
>
> They always have water->(glass)-> air.
>
>
> of course, I could be talking out of my butt....
> I'm sure someone will correct me if i've misremembered.
>
> --
> be safe.
> flip
> Ich habe keine Ahnung was das bedeutet, oder vielleicht doch?
> Remove origin of the word spam from address to reply (leave "+")
>
>