The Solar Eclipse Shadow Cards demonstrate how shadow edge resolution changes during a solar eclipse using various gap and hole sizes. Align the card perpendicular to the sun, adjust the board's orientation, and observe shadow comparisons at different eclipse stages.

Instructions:

1. Place a piece of paper on a clipboard or a large, rigid, white surface like a poster board on thick cardboard.
2. Prop the white board so it faces as close to the direction of the sun as possible.
3. Hold the card close to the board and align it perpendicularly to the sun using the reticle. Adjust until a small dot appears in the center hole.
4. Angle the board to be parallel to the card and rest it against an object for stability.
5. Align the edge of the card's shadow with the direction of the sun's crescent.
6. Rotate the card on its axes to align it perfectly with the sun using the reticle.
7. Observe shadow edge resolution changes during the eclipse.

"Solar Eclipse Shadow Card" by GullDewcat is licensed under Creative Commons - Attribution - Share Alike license. The original design can be found at https://www.thingiverse.com/thing:6527857