Uneven PAR with Mitras LX7 7006 (Freshwater) — Higher PAR in Front Than Center and Si

?? Versión final en inglés para el foro:
Mitras LX7 7006 (Freshwater) gives higher PAR in front than in center or sides — is it possible to adjust intensity by zone to even out PAR?

? I’m using Multichannel Setup on a planted tank with carpeting and stem plants. The light is mounted 18" above water, and the substrate is 30" below the light. I measure 70 PAR in the front, 50 in the center, and 45–50 on the sides. But when I lower the intensity, it drops everywhere — for example, 60 in the front turns into 35 in the center. Is there any way to adjust the light output by zone (like rows or areas) to get a more even PAR distribution across the tank?