40x objective
nWith the 10x lens note the area of interest and using the stage
movement, bring it roughly in the centre of the field.
nRaise the condenser. You may also need to open the iris
diaphragm. High
magnification needs more light!
nRotate the nose piece so that the 40x objective clicks in
place. Be very careful – watch how close the lens is to the slide. Also be
aware that someone may have fiddled with the lenses – that would make the lens
touch the slide.