You don’t often see photographers using gels outdoors in natural light, but why?
I think one of the core reasons you don’t see too many natural light gel shots, is that you need a lot of power and control from your lights to make gels visible in daylight. Whenever we’re outside during the daytime, sunlight has a tendency to creep in everywhere. Even when we’re standing in heavy shadow, there’s still a lot of light on us as the sun bounces around almost endlessly and sneaks into even the most shadowy areas. This is an issue for gels as bright, strong daylight will overpower and ruin a gel shot instantly, making the desired shot significantly harder to achieve over simply setting it up indoors.