The Phi Grid is similar to the Rule of Thirds, but the horizontal and vertical lines are moved slightly inward to align with the Golden Ratio that is often seen in nature. This creates visual harmony that isn’t perfectly symmetrical with roughly 3/8ths of the frame in the upper part, 2/8ths in the middle, and 3/8ths at the bottom.
To apply this rule, place the main subject and supporting elements of your scene along a line or at a point where the lines intersect to create a dynamic focus for the viewer.
Because the intersecting lines are closer to the middle of the frame in the Phi Grid, the foreground can have more impact in the photo, and in some cases, like horizons, the Phi Grid can provide a more pleasing composition than the Rule of Thirds.
NOTE: The Phi Grid composition rule is based on the Fibonacci ratio of 1.618, which might not be the same ratio as your photo.
This icon represented the composition rule on the Wise Camera app and Wise Photos app
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★★★★★ Can’t find a better composition aid for landscape and travel photography (khl.anthony)