A method for reading out an image signal, the method comprising: providing at least one photo-sensitive region (201, 202); providing at least one transfer gate (203, 204) associated with the photosensitive region; providing a charge-to-voltage conversion region electrically connected to the at least one transfer gate (203, 204); providing a reset mechanism that resets the charge-to-voltage conversion region; resetting the charge-to-voltage conversion region with the transfer gate (203, 204) off; after resetting the charge-to-voltage conversion region, measuring a first sample V1 of the reset value; after measuring the first sample V1, operating said at least one transfer gate (203, 204) to transfer charge from the photosensitive region (201, 203) to the charge-to-voltage conversion region; after transferring the charge from the photo-sensitive region (201, 202), measuring a second sample V2 of the signal on the charge-to voltage conversion region with the transfer gate (203, 204) on and measuring a third sample V3 of the signal on the charge-to voltage conversion region with the transfer gate (203, 204) off; after measuring the second and third samples V2, V3, resetting the charge-to-voltage conversion region a second time; after resetting the charge-to-voltage conversion region the second time, measuring a fourth sample V4 of the charge-to-voltage conversion region with the transfer gate off (203, 204) and measuring a fifth sample V5 of the charge-to-voltage conversion region with the transfer gate on (203, 204); determining a high conversion gain measurement using an equation V3 - V1; and determining a low conversion gain measurement using an equation V2-V1-(V5-V4). providing at least one photo-sensitive region (201, 202); providing at least one transfer gate (203, 204) associated with the photosensitive region; providing a charge-to-voltage conversion region electrically connected to the at least one transfer gate (203, 204); providing a reset mechanism that resets the charge-to-voltage conversion region; resetting the charge-to-voltage conversion region with the transfer gate (203, 204) off; after resetting the charge-to-voltage conversion region, measuring a first sample V1 of the reset value; after measuring the first sample V1, operating said at least one transfer gate (203, 204) to transfer charge from the photosensitive region (201, 203) to the charge-to-voltage conversion region; after transferring the charge from the photo-sensitive region (201, 202), measuring a second sample V2 of the signal on the charge-to voltage conversion region with the transfer gate (203, 204) on and measuring a third sample V3 of the signal on the charge-to voltage conversion region with the transfer gate (203, 204) off; after measuring the second and third samples V2, V3, resetting the charge-to-voltage conversion region a second time; after resetting the charge-to-voltage conversion region the second time, measuring a fourth sample V4 of the charge-to-voltage conversion region with the transfer gate off (203, 204) and measuring a fifth sample V5 of the charge-to-voltage conversion region with the transfer gate on (203, 204); determining a high conversion gain measurement using an equation V3 - V1; and determining a low conversion gain measurement using an equation V2-V1-(V5-V4).