New Pokémon Snap - Illumina Spot courses: How to take a photo of Illumina Meganium, Wishiwashi, Milotic, Volcarona and Steelix
This means you can simply focus on taking pictures of Meganium during your first encounter with it. After completing your first journey through this Illumina Spot, you'll be able to complete the LenTalk request, Meganium's Pal. You'll also be able to encounter Pokémon like Eevee during a return visit on Research Level 2. How to take a photo of Wishiwashi Wishiwashi is the second Illumina Pokémon you'll encounter in New Pokémon Snap and it takes its home in the Lental Seafloor Illumina Spot course. Unlike Meganium, you'll need to put in a bit of work to get this Pokémon's picture.
Source: eurogamer.net