Traditional planispheres have been in existence for hundreds of years. While they are useful to the experienced astronomer, they can be very difficult for the beginner to use. There are 3 reasons for this:
1. Traditional planispheres use one small star map to represent the entire dome of the sky above you. Because all of the constellations are on one small map, they are tiny and hard to relate to the actual sky.
2. Another consequence of having the entire sky represented on one small star map is that some constellations are very distorted. The closer you get to the edge of the traditional planisphere star map, the more distorted the constellations become, making many of them unrecognizable to the beginner.
3. To use a traditional planisphere, you hold it above your head (blocking part of the sky) and then align it with true north. You next face the difficult task of relating the small map, positioned awkwardly over your head, to the entire dome of the sky above you, from horizon to horizon.
