). This type of 3-point perspective view angle is referred to as ‘high 3/4 view perspective’ if you are above the object looking down, or ‘Low 3/4 View Perspective’ if you are below the object looking up. When observing an object from above or below, all vertical, parallel lines on the object will also converge at a fixed point which is called the ‘zenith’ (highest point) or ‘nadir’ (lowest point). This type of perspective illustration is also known as a ‘bird’s eye view’ or ‘ariel view’ or ‘worm’s eye view’ of the subject. As with the previous tutorial on two-point perspective, these types of perspective grids are best done using vector drawing software such as Adobe Illustrator, Photoshop vector or CorelDRAW. This is due to the vector software’s ability to have one of a line’s anchor-point’s be dragged to a new location while the other anchor-point remains stationary. Following the instructions in the previous two-point perspective tutorial, our first line to draw will be the picture-plane . From this point, we will follow every step that is described in the 2 pt perspective tutorial with one notable exception, the addition of a third vanishing point – the ‘nadir’ ( ) but instead of projecting vertical lines downward towards the Nadir you would be projecting the vertical construction lines upwards towards the ‘ , draw lines from both horizon vanishing points (LVP & RVP) to the reference points of our subject (green dots). You will also project lines from our third vanishing point, the ‘Nadir.’ For this demonstration I have chosen an arbitrary placement for the Nadir. The further the Nadir is from the subject (downward), the less ‘forced’ the perspective will look. ‘Forced Perspective’ gives the impression that you are viewing the subject through a ‘fish eye’ or ‘wide angle’ lens of a camera. By moving the Nadir downward, you will ‘flatten’ the perspective giving the impression that you are viewing the subject through a ‘telephoto’ or ‘long’ lens. we will start to construct the secondary features of the subject (green dots). The first step will be to establish the secondary vertical plane shown in Once we have completed our construction lines we will start to ‘draw’ our final black outlines by using Adobe Illustrator’s ‘Scissors (C)’ tool to cut the construction lines (in the location of the green dots) and give them new thickness and color attributes. For additional information on this line technique go to the ‘ Continue the process of cutting the construction lines and using Illustrator’s ‘Eyedropper (I)’ tool to sample the attributes of your other black outlines. As was shown in Fig. 7, make your cuts in the location of the green dots. Now that you have completed the process of cutting out all of the necessary lines in out subject, you can eliminate the distraction of the construction lines. Cut them back using the ‘Scissors (C)’ tool, but keep them handy in the event that you need to change the position of, or add additional lines to the subject. The last step is to darken the object’s construction lines, and add weight to all of the exterior and outside edge lines, to increase readability The beauty of learning these perspective grid techniques is that they can be used to deconstruct, or ‘reverse engineer’ a photograph by tracing several parallel and perpendicular line to their vanishing point on the horizon. Wherever two parallel lines intersect you will have discovered the location of the horizon line. By repeating this process on the left and right sides of an object, you can then use each side’s vanishing point to draw a line between the two to form the horizon. was created using a basic 3-point perspective grid as a starting point, then fleshing-out all of the ship’s exterior details and constructing all of the internal information. In the example above, we used 3-point perspective because the view of the ship was hundreds of feet above the horizon line, looking down on the ship from a classic bird’s eye view. By using this angle of view, all of the vertical lines converge at as central nadir located far below the subject. Source.