Wide angle on center radion?

adw · Mar 17, 2016

I have 3 gen3 radions over a 180. I was thinking it might make sense to put a wide angle lens on the center one to help with shading. Anyone have any thoughts?

mfinn · Mar 17, 2016

I would do all 3 instead of just 1.
Keep all 3 fixtures on the same intensity level.

adw · Mar 17, 2016

Seems like the wide angle on the ends would cause light to spill out.

mfinn · Mar 17, 2016

I've seen people talk about light spillage, but I have 4 gen 3 Radions with wide angle lens over my 72" tank and I honestly don't see this light spillage that has been talked about.
The fixtures on the ends of the tank are 9" from the edge of the tank to the center of the fixture.
It may be because I use the RMS mounts and the lights are 8" from the water. I used a diy light rack before the RMS system and the lights were a touch higher and didn't see this light spillage problem.

Kungpaoshizi · Mar 17, 2016

I want to say I recall a guy doing a comparison with a par meter, he said on average, the wide angle lenses produced 5-15% less par, with the same intensities. I myself consider the undergrowth-necrosis you see with other led's less of an issue as with the 120's you're blasting light to more areas, thus increasing the ambient light in the tank. This is what I believe to make t5's and mh's better at the undergrowth problem... (light spraying everywhere bouncing off the sides of the tank too)
Anyways, I switched to the 120's awhile back, don't think I'll ever consider the narrow lenses again, unless I had a 4ft deep tank or something..

Staggs · Mar 17, 2016

Not sure how accurate this is, but I've used it to help figure out my intensities after I went from a standard lens to a wide angle lens on my radion.

http://www.aquaticlog.com/radion

rmcaum · Mar 17, 2016

You could buy two sets of the wide angle lenses. Install one in the middle. The kit comes with two lens plates. You could install the other set, 1/2 each on the inside puck of the outside radions. Leaving only the two outside pucks of six total as the original lenses.

mcarroll · Mar 17, 2016

adw said:
I have 3 gen3 radions over a 180. I was thinking it might make sense to put a wide angle lens on the center one to help with shading. Anyone have any thoughts?

Before you do anything:

If things are working well with the tank now I don't think I'd mess with your setup.

If you're dissatisfied enough to mess with it, or if the current setup is not working out....the first thing you need to do is get a [HASHTAG]#lux[/HASHTAG] [HASHTAG]#meter[/HASHTAG].

Start with a free app for your smartphone camera so you can take some measurements now to get going, but order a $15 (shipped) lux meter for use later...much better.
Blending them won't be too bad if you use a meter to do it, but I'd be concerned about intensity. You will have to turn down the end units by X amount.
If you're using a meter it'll be easy to see if you have enough power to pull it off.
Last but not least: if your reef is already established under the three lights, you really don't want to vary average intensity over the tank by much at all.

You'll have to test your idea to find out of course, but I can imagine you maybe needing an additional unit if spread/shading is currently a real problem.

Consider that you might prefer a different style of light vs investing more money into the same lighting.

"Spilled Light"
Part of the problem with switching to "wide" (120º) lenses is that the light field expands equally in all directions - mostly over the front and back of the tank vs in the tank where you want it.

Whether spilling light outside the tank bothers you is aesthetic.

In the old days of halide and T5 it pretty much couldn't be avoided. At least with LED, you aren't getting a "bonus" dose of UV.

With LED's the lighting scenario has changed for the better "times 11".

In spite of that, some folks still build LED's to replicate halide or T5 lighting and some even include the "spill factor" - maybe just because they are used to their tank lighting up their room and the tank looks good. Some don't even notice spill, but to some, lighting the whole room reef-blue is annoying. (I'm the latter. My gu10 fixture barely even lights up the glass on the tank, let alone the room beyond. Glass-scraping is virtually eliminated on that tank.)

Either way, the fact is that the light from your fixture belongs in the tank, and the light that's in your room is not in the tank.

It's, by definition, a waste. It could be quite a bit or almost none (if you can look back as some example lighting diagrams I've posted in other threads...) but wide angle lenses do promote more spill vs less if some care isn't taken during installation. They also promote more light-reflection off the water surface, and this can be significant by comparison with light directed through more narrow lenses. There's a gradient of loss, but a significant swing toward reflection outside of 70º, if I recall correctly.