Slide film was traditionally used by nature photographers to get vibrant colors in their scenes. It’s typically more expensive than negative film, isn’t as lenient when it comes to exposures, and is processed using the more expensive E-6 chemicals. Color negatives or C-41 film is more widely available, less expensive, and typically less expensive to process. You can over-expose negative film by several stops and still get a usable image. In the end, though, the best film stock is the one you enjoy using the most.