Canopy Diffuser

[DipSpit]

So inside of the canopy (which measures 36" x 36" OD) I have 4 SB reef lights and a 250w Radium w/ Spyder reflectors. I want to put a sheet of wither polycarbonate or glass over the bottom, inside the canopy to either a.) help diffuse the light into a uniform source (I do know MH's don't need this but, it wont hurt it I don't believe) or b.) simply for aesthetic reasons (so that when viewed from below it is a single glowing pane).

Pic for reference:

Is frosted glass my best bet? Also looking at textured glass?

My concerns are the full spectrum getting through the glass. UV Filtering (but the MH's put out so much some reduction may be a good thing) and durability is sort of a concern also. The top of the canopy is open air so heat dispersion shouldn't be an issue. Tank will be SPS dominate if it helps.

Side notes: * I have had some expressed interest in a build thread which I will do upon completion.

Thanks in advance for any input/experience.

 

[Bluefish9]

Not that this helps but just a curiosity of mine... do you think diffusing the light will prohibit the shimmer effect that LEDs and MH's are known for?

 

[DipSpit]

Not that this helps but just a curiosity of mine... do you think diffusing the light will prohibit the shimmer effect that LEDs and MH's are known for?

Maybe - but not really an issue for me.

 

[Marc.The.Shark]

This may help
https://www.reef2reef.com/threads/what-can-be-used-as-a-diffuser.273917/

Nice setup BTW!

 

[DipSpit]

This may help
https://www.reef2reef.com/threads/what-can-be-used-as-a-diffuser.273917/

Nice setup BTW!

Thanks! Its a slow process but rewarding.

As for the linked thread - I read it before I came here with no real answers sadly I am looking for something more definitive - esp towards the aesthetic aspect.

 

[Bluefish9]

Maybe - but not really an issue for me.

If you dont mind, can you report back in regards to the shimmer after you try diffusing the light? I have similar lighting and was also curious about diffusing it.

 

[DipSpit]

If you dont mind, can you report back in regards to the shimmer after you try diffusing the light? I have similar lighting and was also curious about diffusing it.

I will I just need some educated opinions. Trying to avoid dropping hundreds on glass sheets and what and narrow the focus (of my guesses) a bit.

 

[Marc.The.Shark]

Well, I can tell you that etched glass was not an option for me. When I was doing my cabinet doors in my kitchen & going to add some frosted glass in a couple of them, I looked into the frosted glass option & was told that anytime you touch the frosted side the oil in your skin will leave a spot. Figured that was bound to happen & didn't want spots all over, so I went with a stick on there too. I guess the only way to be sure what you have is to gain access to a par meter & try some different material until you're happy with the look & #'s. There hasn't been a lot of testing done on this that I could find, but it seems that at least some led manufacturers are entertaining the idea & I'm sure it will grow in popularity

 

[DipSpit]

Yeah that is this issue, I feel like I am in uncharted waters (heh, punny) and no matter what Im going to have to get a bite the bullet for the community and do some testing.

 

[Marc.The.Shark]

Sorry, the info I found on mine was years ago on ReefCentral. If you get a par meter start with the cheap stuff first! Lol. Also, it might be worth a search over there, cause I think the thread that I found over there, the guy tested different material including the plastic diffusers that you use for fluorescent lights. If I remember, it was a pretty thorough job. Might narrow your choices down some

 

[Bluefish9]

What about a piece of lexan combined with some frosted glass FILM? Its inexpensive enough that even a failed attempt wouldn't break the bank...
Just recently, we rented a vacation home in the keys and the bathrooms had the frosted film on the windows for privacy. It let a TON of light in and seemed to be very durable as they had it in the shower window as well.

Just a thought

 

[Marc.The.Shark]

What about a piece of lexan combined with some frosted glass FILM? Its inexpensive enough that even a failed attempt wouldn't break the bank...
Just recently, we rented a vacation home in the keys and the bathrooms had the frosted film on the windows for privacy. It let a TON of light in and seemed to be very durable as they had it in the shower window as well.

Just a thought

Yeah, that's exactly what I use.

 

[saltyfilmfolks]

Frosted glass is best but you want a thin thin grade. All uv is cut by glass or plastic. I.e. $5 sunglasses uv.
Check out the new Phillips
Any time you diffuse light it goes red just a bit thus thinner is better.
On a 20k radium not sure that would matter. The SB full up color temp is about 16k I belive
Thick accrylic and thin film may work but remember heat. I'm sure you are.

 

[saltyfilmfolks]

IMO w four sbs and a mh. You prob have plenty of power. You can consider pulling the lenses. A lux meter will tell you how much you lose.
At 12 in a stock SB will give you 100,000 lux. That's full daylight intensity.

 

[DipSpit]

http://www.tapplastics.com/product/plastics/cut_to_size_plastic/acrylic_sheets_p95_matte/513

This is what I'm leaning towards - but I read the a textured surface is needed to bend the beams of light? Im no scientist.

EDIT: Maybe a bit more frost? If film, which Film? My head hurts, lol.

 

[DipSpit]

IMO w four sbs and a mh. You prob have plenty of power. You can consider pulling the lenses. A lux meter will tell you how much you lose.
At 12 in a stock SB will give you 100,000 lux. That's full daylight intensity.

The tank is 32" deep though.

 

[saltyfilmfolks]

http://www.tapplastics.com/product/plastics/cut_to_size_plastic/acrylic_sheets_p95_matte/513

This is what I'm leaning towards - but I real the a textured surface is needed to bend the beams of light? Im no scientist, dang.

Diffusion by nature is bending the beams. It's just smaller. Bending is spreading.

 

[saltyfilmfolks]

That's what the meters for

The tank is 32" deep though.

if the lights are up and the tank is empty put the meter in the bottom.

 

[DipSpit]

That's what the meters for

if the lights are up and the tank is empty put the meter in the bottom.

Hmm, just two problems though: I don't have a meter, and, wont water effect measurements - especially the absence of it?

 

[bigroost]

Hopefully I can give some kind of update to that other thread soon, I have the acrylic cut and the film applied. I haven't had a chance to find away to attach it or borrow a par meter to see how much difference it will make. After tomorrow I will be off work for the next month, so hopefully I can atleast let you know how that one film worked out.