A method of controlling an electrowetting element of an electrowetting display device comprising a control apparatus, the electrowetting element comprising: a first support plate; a second support plate; a first fluid; and a second fluid immiscible with the first fluid, the first fluid and the second fluid located between the first support plate and the second support plate, the first support plate comprising: an electrode; and an insulating layer between the electrode and the first and second fluids (11, 12), the insulating layer having a surface, display effects of the electrowetting element depending on an extent that the first and second fluids (11, 12) adjoin the surface, in dependence on a voltage applied to the electrode, the method including: a) receiving, by the control apparatus, data representing a first display effect for display by the electrowetting element; b) receiving, by the control apparatus, data representing a subsequent display effect for display by the electrowetting element consecutively after display of the first display effect; c) comparing, by the control apparatus, data representing the first display effect with data representing said subsequent display effect to determine a difference indicative of a change of the extent the second fluid adjoins the surface between display of the first display effect and display of the subsequent display effect; d) determining, by the control apparatus, that said difference exceeds a threshold value; and, in response, e) outputting, by the control apparatus, data for driving the electrowetting element to display a different display effect, instead of the subsequent display effect, consecutively after displaying the first display effect. a first support plate; a second support plate; a first fluid; and a second fluid immiscible with the first fluid, the first fluid and the second fluid located between the first support plate and the second support plate, the first support plate comprising: an electrode; and an insulating layer between the electrode and the first and second fluids (11, 12), the insulating layer having a surface, display effects of the electrowetting element depending on an extent that the first and second fluids (11, 12) adjoin the surface, in dependence on a voltage applied to the electrode, an electrode; and an insulating layer between the electrode and the first and second fluids (11, 12), the insulating layer having a surface, display effects of the electrowetting element depending on an extent that the first and second fluids (11, 12) adjoin the surface, in dependence on a voltage applied to the electrode, the method including: a) receiving, by the control apparatus, data representing a first display effect for display by the electrowetting element; b) receiving, by the control apparatus, data representing a subsequent display effect for display by the electrowetting element consecutively after display of the first display effect; c) comparing, by the control apparatus, data representing the first display effect with data representing said subsequent display effect to determine a difference indicative of a change of the extent the second fluid adjoins the surface between display of the first display effect and display of the subsequent display effect; d) determining, by the control apparatus, that said difference exceeds a threshold value; and, in response, e) outputting, by the control apparatus, data for driving the electrowetting element to display a different display effect, instead of the subsequent display effect, consecutively after displaying the first display effect. a) receiving, by the control apparatus, data representing a first display effect for display by the electrowetting element; b) receiving, by the control apparatus, data representing a subsequent display effect for display by the electrowetting element consecutively after display of the first display effect; c) comparing, by the control apparatus, data representing the first display effect with data representing said subsequent display effect to determine a difference indicative of a change of the extent the second fluid adjoins the surface between display of the first display effect and display of the subsequent display effect; d) determining, by the control apparatus, that said difference exceeds a threshold value; and, in response, e) outputting, by the control apparatus, data for driving the electrowetting element to display a different display effect, instead of the subsequent display effect, consecutively after displaying the first display effect.