On the fifth day of the Genshin Impact Graph Adversarial Technology Experiment Log event, you'll be asked to photograph Basically Purple Teyvat Products. There are a ton of them in Inazuma, but I'll show you some options in Mondstadt as well.
Check out some of the photography subjects I've collected below to quickly use up the day's film. Don't forget that you can exchange films with Lepine-Pauline up to seven times, and you can give excess films to friends.
Genshin Impact Basically Purple Teyvat Product locations – Graph Adversarial Technology Experiment Log
Head to the Grand Narukami Shrine, where you'll find a ton of Sakura Blooms floating around. You can take photos of them using the Image Sampling Kamera to get photos in various hues.
You can find small Onikabuto scattered across Inazuma. I don't recommend intentionally farming for them, as they're extremely hard to spot. But if you happen to spot one, you can take a photo! There's one close to the Kamisato Estate that you can pay a visit if you're around the area to claim Reputation rewards.
Amakumo Fruit & Naku Weed
Head to the Teleport Waypoint east of Amakumo Peak to find a ton of Amakumo Fruits scattered around the area. Each cluster will have two fruits, which can be individually photographed to count toward the day's 10-film limit. Likewise, you can also find a few Naku Weeds, which match the day's photography theme.
Head to the Wolvendom Teleport Waypoint and follow the path leftward (toward the Lupus Boreas boss) to find some Wolfhooks scattered around the area. They can be photographed for the day's prompt.
While farming for any of the above materials, you'll also find Electro Crystals along the way. You can take a photo of them as they match the day's prompt.
To find more photography subjects, check out Where to find Staff-Wielding Opponent in Genshin Impact – Graph Adversarial Technology Experiment Log here on Pro Game Guides.