In these scopes, the image is formed as the object materials move through a liquid medium. Oilcells are the slow-motion equivalent to the tumblescope, with the added feature that the changing image is visible during its slow transition from one form to the next.

As with the tumblescope, the random movement of the contents of the cell means that once an arrangement and its' resulting image has been disturbed, it can never be exactly recapured.