Lenses are bad, just saying.

[Flexy123]

I built my fixture about 4+ years ago, and I built it with these glass lenses. All I can say is that the lenses are absolutely not worth it, and they cause much more troubles than having any real benefits, IMO.

First, the lenses are the heaviest part of the entire fixture, they make the lights extremely heavy. Since my light is a DIY project, the heatsink has holes above the COBs where the wires go in. This means that over many months, dust and whatever gets inside, and the lenses get dirty in time. So every year or so, it's a pain in the ass to remove them and clean them.

Also...when I compare the spread with lenses and without, I do not see much difference, if at all. In fact I like the spread without the lenses better than with the lenses. Those COBs on my fixture where I don't have the lenses, I don't see them getting dirty either, despite my light outside in a VERY dusty environment. And if a COB should get dirty, you can wipe them with alcohol and a paper towel easily. Just saying if you're a DIYer COB builder, save yourself the hassles with the lenses.

[grisbi]

hello guyz!i disagree with you sir,
ive been mesuring a huge difference with a par meter , in litlle closet when cob runing @70w with and without glass lens optic 80degres.
cheers

[TEKNIK]

If you are using glass lenses you should have them sealed so dirt and moisture can not damage the COB. Leds are porous so if you use a lens properly they will last a lot longer than an exposed led. Regarding beam angles well that's up to the lens you choose, if you want a long lasting fixture a fully sealed unit with a breather will last for many many years, if you swap out your COBs every 2 years then don't worry about a lens. Just don't get them wet cause you can have issues with gremlins

[Nuggie]

In the testing that I saw online, I would have to agree - waste of money

[TEKNIK]

In the testing that I saw online, I would have to agree - waste of money

Can you post a link to the test please?
I have not seen any conclusive tests of fully sealed and protected leds running in a grow room against an exposed led running in a grow room.
I want to see just how effected the leds are and how the performance drops once the leds become contaminated.
This is something I plan to test at some stage over 10,000 hours to compare the 2 and I believe that the product protected by the lens will perform better after 10,000 hours

[Nuggie]

I can't remember where I saw it, changed gears from cobs to strips and left everything cob behind. Take it or leave it.