This overview only applies to a front table configuration and describes what is seen on the screen.
When the image is shifted in one direction, a black border appears at the opposite side
The adjusting screws are sealed with glue: before trying to turn the screws, warm up the glue using a hair
dryer until it becomes weak. Now the screws can be tightened or loosened without risk of damage.
The nominal position of the folding mirror is the position where the top plate of the folding mirror is at the
same level as the top of the three studs.