LED's - 90 degree or 120 degree optics?

[Ratpack]

I have two Reef Radiance DM-155E's and they came stock with 90 degree optics, but I looked at the new mdels they have and they all seem to come with 120 degree optics. So my question is, does anyone have any kind of comparison on the two optics? I know the spread will be more which would help from having to mount them so high, but what is the PAR impact? I am trying to dtermine if I need to call Rick and order some 120 optics and switch mine out.

 

[reefer gladness]

LED's without optics are 120 degrees so if that's what you want then remove the optics you have now.

Obviously 90 degree optics don't give you as much spread as the 120 degree but offer increased output in a narrower beam. Very important to consider the mounting height over the water. The higher the fixture is mounted the more spread you get with lower PAR but the different color LED's blend better.

 

[Lyn002]

Many lights use mix degree optics lens, such as 60/120, 90/120...I think it's a nice design to provide High PAR value and the most suitable spread area...