A microscope with an exchangeable intermediate tube that is inserted between the microscope objective and an ocular eyepiece instead of the tube lens and which is adjustable in a defined manner with respect to its height and has relay or transfer optics with an essentially constant intersection length, comprising, in the observation direction, a first lens group with a long focal length, preferably greater than 10 m, and a second lens group with a short focal length whose common focal length corresponds to the focal length of a standard tube lens, preferably approximately 164 mm, wherein the distance between the first and second lens group is adjustable.