You cannot use () to designate multiple outputs in MATLAB: you need to use []
[aerial_points_ortho_points] = cpselects('aerial,light.jpg', ...
movingpoints, fixedpoints, ...
'wait',true);
In the special case where you only have one output variable, you can leave out the []
aerial_points_ortho_points = cpselects('aerial,light.jpg', ...
movingpoints, fixedpoints, ...
'wait',true);