Imax nature documentaries are renowned for their amazing photography. But “Pandas,” which opens Friday at the Great Clips Theater at the Minnesota Zoo, has something going for it that makes it unique — a cuteness factor that is off the charts. Yes, the movie has a serious message about how the species is struggling to survive because the bears are being squeezed out of their natural habitat. But watching these adorable, roly-poly creatures, it’s impossible not to be swept up in an aura of “aww” that turns your insides all soft and gooey. Kristen Bell — yes, kids, she was the voice of Anna in “Frozen” — provides the family-friendly narration, and versatile composer Mark Mothersbaugh has come up with a soundtrack that underscores the pandas’ playfulness. By the time it’s all said and done, you don’t just want to help save the pandas, you want to take one home with you.