How do I get back to the Orrery with Shield 3?

Hint 1 of 8:

Shield 3 is your key.

Hint 2 of 8:

Return to Geffrye's studio and go through the northeast door to the Bell
Tower.

Hint 3 of 8:

Go up the ramp and ascend the staircase to the left.

Hint 4 of 8:

At the top of the staircase is a door with a shield-shape panel beside it.

Hint 5 of 8:

Insert Shield 3, but don't leave it there.

Hint 6 of 8:

Remove the Shield and turn around.

Hint 7 of 8:

Open the panel in the east wall and go through.