Camera front seal assembly

A seal assembly comprising:

• a first retainer having an opening, said first retainer defining an axis extending through said opening;
• a second retainer disposed in fixed relation to said first retainer, said second retainer facing said first retainer in spaced relation along said axis;
• a barrel extending through said opening, said barrel having a cylindrical barrel wall;
• a collar having a side wall facing said barrel wall, said barrel being movable relative to said collar;
• a stack of alternating lesser and greater rings disposed between said first retainer and said second retainer and between said barrel wall and said side wall, said lesser rings being movable relative to said greater rings in directions radial to said axis, said stack having a centered state wherein each said lesser ring more closely adjoins said barrel wall than said side wall and each said greater ring more closely adjoins said side wall than said barrel wall.