question on saturation?

this may be a stupid question, Im editing pics taken last tues. when i notice a huge diff in saturation and color between 2 sets of shots. i used 2 diff lenses one a 28-135 the other is a 24-105 with similar settings. I just got the 24-105 so still not so familiar, with the 24-105 the colors were more vibrant and real but at the same time looks over saturated over the 28-135. is this due to the lens? do i need to adjust my camera settings to suit each lens? WB was @ auto.? is this bec of the setting? color of the t shirts, first is the 24-105 2nd is the 28-135.

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You have a difference in lighting here and that is affecting image quality. The top image it appears the shadows are soft - like it was overcast and this will allow more color saturation whereas, in the second image, you have bright sunlight and a very distinct shadow - bright sun will wash saturation which is one of the reasons why photographers try to not shoot when the sun it highest.

thanks. starting to get clear to me now. both were shot at the middle of the day probably an hour apart.