Collage issue(Urgent)

I have one problem about DL.2 collage.I use two DL.2 units to collage,I programme "enhance collage" and use the grid to have the alignment to make sure it's not fuzzy,I also use the "fade left and right" for blending.If the clips are in low colour temperture or kind of abstract stuff,the image is seamless;if the clips are in high colour temperture and some specific stuff,the overlapping area is visible,and the overlapping area is yellow.
I think the lamps' not same luminous though they both are new.
Do you guys have suggestion for the problem?