  Structural color filters use nano-sized elements to selectively transmit
incident light, offering a scalable, economical and environmentally friendly
alternative to traditional pigment- and dye-based color filters. However, their
structural nature makes their optical response prone to spectral shifts
whenever the angle of incidence varies. We address this issue by introducing a
conformal VO2 layer onto bare aluminum structural color filters. The
insulator-metal transition of VO2 compensated the spectral shift of the
filter's transmission at a 15{\deg} tilt with 80% efficiency. Unlike solutions
that require adjustment of the filter's geometry, this method is versatile and
suitable also for existing structural filters. Our findings also establish
tunable materials in general as a possible solution for angle-dependent
spectral shifts.
