Since we know that the real point xyz will remain in the same place in real space from one frame of the image to the next we can make the point a constant even though we do not know where it is.
Pošto znamo da će prava tačka xyz ostati na istom mestu u realnom prostoru od jednog frejma sa slike do drugog možemo ostaviti tačku konstantnu čak i kada ne znamo gde je.