Acrylic lid and par loss?

[saltyfilmfolks]

Understood. and agree it's ALWAYS "complicated"..

Bottom line though, and regardless of spectrum shifts..Does "common" eggcrate block more PAR than glass? Less par?

Should we add the complication of a more "coherent" beam of light (i.e LED's) hitting plastic barriers?

One of the things I found was that PAR increased for lights w/ inherently poor reflectors..which would be somewhat obvious..and the lights had to be a certain distance
as well....
Second obvious thing is the taller the cells the more light loss due to stuff bouncing around inside and absorbance..
Egg crate "should be" poorer at transmission w/ LED's than clear glass.

Guess even my "averaging" is probably pss poor..
So for a strictly PAR metric.. doubt if you can beat glass.. until you really foobar the glass w/ salt/dirt...
Certainly not buying an increase in PAR w/ eggcrate w/out very specific circumstances..
Too much contrary evidence though most is a bit "qualitative"..
As I said only PAR measurements but Danas that "I" found show losses in the visible spectrum overall and from the quote above so does your industry..

No not considering gas exchange ect here...and not implying one is "better'' than another in a blanket statement ..





SEE post 15
http://wamas.org/forums/topic/26776-eggcrate-for-focusing-light/

Understood.
But mostly I’ll agree to , it gets complicated. That’s why have acrylic that gets really dirty, don’t meter it and have seen no change in my corals.

Bottom line, a transparent thing blocks less light than a solid thick thing. The thinner and thinner it is , the less Light it blocks.

So, IMO , one who wants to keep Less Light blockage would use the thinnest thing possible , and if you need structure too, the thinnest egg crate possible. Although the regular stuff like Dana likes , it adds a really really nice softness to the Light IMO.

 

[oreo54]

Bumping this useful thread. Tom's experiment is post #15. Someone should recreate this w/ LEDs.

2008...

http://wamas.org/forums/topic/26776-eggcrate-for-focusing-light/page-2

for fun..

 

[Dana Riddle]

That's because salty is the Best!

Of course he is!

 

[Dana Riddle]

Nice work! You have correctly pointed out that eggcrate focusing doesn't always work, and I don't think it will focus light from LEDs. The work I did with eggcrate was done way back in the 90's when metal halides were the lamps of choice, and, frankly, I had forgotten the experiment with the fluorescent lamps. Thanks for jiggling some of my ancient synapses.

Understood. and agree it's ALWAYS "complicated"..

Bottom line though, and regardless of spectrum shifts..Does "common" eggcrate block more PAR than glass? Less par?

Should we add the complication of a more "coherent" beam of light (i.e LED's) hitting plastic barriers?

One of the things I found was that PAR increased for lights w/ inherently poor reflectors..which would be somewhat obvious..and the lights had to be a certain distance
as well....
Second obvious thing is the taller the cells the more light loss due to stuff bouncing around inside and absorbance..
Egg crate "should be" poorer at transmission w/ LED's than clear glass.

Guess even my "averaging" is probably pss poor..
So for a strictly PAR metric.. doubt if you can beat glass.. until you really foobar the glass w/ salt/dirt...
Certainly not buying an increase in PAR w/ eggcrate w/out very specific circumstances..
Too much contrary evidence though most is a bit "qualitative"..
As I said only PAR measurements but Danas that "I" found show losses in the visible spectrum overall and from the quote above so does your industry..

No not considering gas exchange ect here...and not implying one is "better'' than another in a blanket statement ..





SEE post 15
http://wamas.org/forums/topic/26776-eggcrate-for-focusing-light/

 

[Aardvark1134]

Egg crate is great...unless one of your goals is to keep in the 2+gallons a day of extra evaporation and all the moisture that causes

 

[Ross Petersen]

Understood.
But mostly I’ll agree to , it gets complicated. That’s why have acrylic that gets really dirty, don’t meter it and have seen no change in my corals.

Bottom line, a transparent thing blocks less light than a solid thick thing. The thinner and thinner it is , the less Light it blocks.

So, IMO , one who wants to keep Less Light blockage would use the thinnest thing possible , and if you need structure too, the thinnest egg crate possible. Although the regular stuff like Dana likes , it adds a really really nice softness to the Light IMO.

Hey Salty. I wanted to get your advice - I need a cover for a 127-gallon classroom reef tank. I have a nice mesh cover but want a cover that I can use to reduce evaporative loss in the summer when I'm away (only a few weeks / year) and to prevent particulate wood matter from getting in on rare occasions. Would you recommend glass? Acrylic? Thanks

 

[Aardvark1134]

Acrylic tops are much lighter, reflect less, insulate better (less condensation on it), and don't make a dangerous mess if you drop it on the floor.

 

[Reefman71]

I wonder how this would affect PAR