Methods, devices, and systems for offset cancellation in an amplifier are disclosed, wherein the amplifier inputs may be exposed to large loads from an array of pixel columns coupled in parallel. During a cancellation phase, an amplifier offset may be canceled by selectively coupling a first amplifier output to a first amplifier input and a second amplifier output to a second amplifier input. During a portion of the cancellation phase, a buffer may use the first amplifier input to drive a first pixel signal. During a different portion of the cancellation phase, the buffer may use the second amplifier input to drive a second pixel signal. To sense the pixel columns during an amplification phase, the first and second pixel signals are coupled to the first and second amplifier inputs, respectively, with the result that the amplifier offset and the buffer offset are cancelled from the amplifier output.