Allow 40min
Aim:
To create a perspective grid using a single measurement and
three vanishing points. This lesson is to consolidate and further
the notion of perspective 'scale'. That is, as things of equal size
recede they appear smaller. This time we will use the CVP and a
familiar and logical structure, a railway
line.
Materials:
The sketch pad,
HB pencil,
ruler.
Construct margin and title box then:
a) Construct the same light lines as in stage a, b, c, d, of the previous lesson until we get the lines shown above.
b) This time we firm in the 'diagonals' which become railway line 'sleepers'. Notice here we use a more simplified method of construction.
c) Keep adding sleepers.
d) After the student has completed the
drawing to the stage above ask:
What shall we call the line that
joins LVP, RVP and CVP? (answer 'horizon line').
How wide are
railway tracks? (remember the old movies of people tied to railway
lines? - answer about 5feet).
If the distance between the
sleepers is 5 feet what is the distance between the second add
fourth sleepers?
e) Add the extra light lines on the ground (two horizontal and three to the CVP). We are going to build a station about 30mm (1,1/4") from track 60mm wide.
f) Add the vertical lines 50mm (2") high and join to CVP
g) Firm in the lines as shown and
ask:
How high is the building? The student should measure the
width of the tracks on the line directly opposite the front edge of
the station and apply that 'scale' to the building's height.
Objects an equal distance away from the 'observer' are subject to
the same measurements of 'scale ' at that distance. In this
drawing the scale is discovered by knowing the width of the track at
that distance.
h) Add the telegraph lines and poles and have the student determine their height and distance apart.
Clean up and print in the title as
shown.
Encourage the advanced students to add three 12 foot cacti
at various locations in the landscape.
By John Hagan
Information supplied by: http://www.geocities.com