A display comprising: a light source, a first spatial light modulator, the first spatial light modulator comprising a plurality of first elements switchable between ON and OFF states, the light source arranged to direct light onto the first spatial light modulator, a second spatial light modulator, transfer optics disposed to direct light modulated by the first spatial light modulator onto the second spatial light modulator, and a driver configured to generate first and second control signals for the first and second spatial light modulators respectively based on image data, the image data defining an image frame to be displayed, wherein: the driver is configured to generate a spatial dithering pattern of ON and OFF states applied to the first spatial light modulator based upon the image data for the image frame and upon a defect map, the spatial dithering pattern having a spatially-varying density, the defect map indicating stuck ON or OFF states of defective elements of the first spatial light modulator; the driver is configured to generate the first control signal so as to set elements of the first spatial light modulator according to the spatial dithering pattern of ON and OFF states substantially continuously during displaying of the image frame, wherein defective elements that are stuck in an ON state are included in the dithering pattern as being ON and defective elements that are stuck in an OFF state are included in the dithering pattern as being OFF; the transfer optics are characterized by a transfer function that blurs light originating from the first spatial light modulator at the second spatial light modulator. a light source, a first spatial light modulator, the first spatial light modulator comprising a plurality of first elements switchable between ON and OFF states, the light source arranged to direct light onto the first spatial light modulator, a second spatial light modulator, transfer optics disposed to direct light modulated by the first spatial light modulator onto the second spatial light modulator, and a driver configured to generate first and second control signals for the first and second spatial light modulators respectively based on image data, the image data defining an image frame to be displayed, wherein: the driver is configured to generate a spatial dithering pattern of ON and OFF states applied to the first spatial light modulator based upon the image data for the image frame and upon a defect map, the spatial dithering pattern having a spatially-varying density, the defect map indicating stuck ON or OFF states of defective elements of the first spatial light modulator; the driver is configured to generate the first control signal so as to set elements of the first spatial light modulator according to the spatial dithering pattern of ON and OFF states substantially continuously during displaying of the image frame, wherein defective elements that are stuck in an ON state are included in the dithering pattern as being ON and defective elements that are stuck in an OFF state are included in the dithering pattern as being OFF; the transfer optics are characterized by a transfer function that blurs light originating from the first spatial light modulator at the second spatial light modulator. the driver is configured to generate a spatial dithering pattern of ON and OFF states applied to the first spatial light modulator based upon the image data for the image frame and upon a defect map, the spatial dithering pattern having a spatially-varying density, the defect map indicating stuck ON or OFF states of defective elements of the first spatial light modulator; the driver is configured to generate the first control signal so as to set elements of the first spatial light modulator according to the spatial dithering pattern of ON and OFF states substantially continuously during displaying of the image frame, wherein defective elements that are stuck in an ON state are included in the dithering pattern as being ON and defective elements that are stuck in an OFF state are included in the dithering pattern as being OFF; the transfer optics are characterized by a transfer function that blurs light originating from the first spatial light modulator at the second spatial light modulator.