I put together two pairs of lights, each has two Citi 048-1818's (identical pairs on each set). There was a difference between the amount of light put out by them that was obvious to my eye. I have no light meter, but it is also obvious in photos.
One pair is connected (in series) to an HLG-120H-C1400A, and should be running at about 70w each (as I understand it)
The other pair is connected (in parallel) to a HLG-120H-48A, and should be running at 78.5w each -- according to CobKit's website (they are on the SST-X heatsinks).
So, why are the ones connected to the HLG-120-C1400s obviously significantly brighter?
(I have other photos, no matter what angle I take it at, one set is much brighter than the other).
![1818_comparison-1.JPG](/data/attachments/3026/3026116-c7eadffeabf29da4931d154a6c45851f.jpg)
![Screen Shot 2017-04-16 at 9.59.00 AM.png](/data/attachments/3026/3026118-69c7a090cbe35106be39019426534088.jpg)