In Tears of the Kingdom, the land of Hyrule is not just a place to go to if you're looking for monsters to fight and dragons to vanquish. It is a beautiful, picturesque landscape that deserves to be appreciated for its visual merit alone.
Apparently, the residents of Hyrule feel the same way, as some of them are keen to capture a moment of pure bliss for themselves too. Anly from Lakeside Stable is one of them, and he'll tell you all about it in "A Picture for Lakeside Stable" side quest.
Starting The Quest
You will need to visit the Lakeside Stable in the Faron region. The Rabella Wetlands Skyview Tower is the closest skyview tower to this region. To start the quest, head inside the stable and locate the empty wooden picture frame on one side of the interior, just to the side of the newspaper reader.
Interact with the empty picture frame, and Anly, the Stable owner, will initiate a conversation with you. He will talk about how he is waiting for a picture of Flora Falls on a clear day to hang up in the picture frame.
To complete the quest, you will need to fulfill Anly's request and take that picture using the Camera.
Waiting For Clear Weather
In order to take the picture for Lakeside Stable, you will need to wait for clear weather. There are three types of weather in this area: cloudy, rainy, and clear. Cloudy and rainy weather conditions are much more common than clear skies.
Fortunately, there is a way to cycle through different weathers in Tears of the Kingdom by waiting by a fire. Just a little ways ahead of the stable, there is a small wooden canopy with a hearth just under it. This fire is protected by the rain so it won't go out. You can easily cycle through the weather by interacting with this fire and waiting until the next day.
Taking The Picture
When the weather clears up, you can head to the Floria Bridge. It is located right in front of Floria Falls and follows the main road from the Lakeside Stable.
On the bridge, open up your Camera and aim it towards Floria Falls. If the day is clear, you'll see a small red exclamation mark on the top right of the UI. Press A to picture and save it to your Album.
If you don't see a red icon on the top right when taking a picture of Floria Falls, you're either too far away, or the weather is rainy or cloudy. Move to the center of the bridge and wait for clear skies before trying again.
Completing The Quest
Once you have the picture saved in your Album, return to the Lakeside Stable and interact with the empty picture frame again. Anly will call you up to the counter again, and this time you can show him the picture of Floria Falls from your Album. Anly will fall in love with the picture and agree to hang it up inside the stable.
He will reward you with a cooked dish and 1 Pony Point for your efforts.