OBSERVED PERSPECTIVE

Much of the time, perspective on buildings in the landscape holds no problems, especially when the subject building is in the distance. However, in some awkward situations, where perhaps the viewing angle is complicated and there are numerous different planes of adjacent buildings, applying the basic rules of perspective can be a challenge. In the scene below, which embraces those awkward aspects, things are further complicated by some parts of the house being obscured by vegetation and a fence.

The diagram (below), which features the main lines of the building, will give you an idea of to how to tackle the drawing with a reasonably accurate result. First, establish a horizontal base line – an imaginary line from which you can measure all the other important points above or below that line. I have drawn a hand holding a pencil vertically at arms length – literally a rule of thumb – where the thumb is moved up and down the pencil to ascertain the height of, say, the distance from the base line to the top of the chimney. If you assess each important point in this way, always keeping the pencil at arm’s length, it will reveal whether the point at the left-hand end of the roof ridge is higher or lower than the top of the chimney, and other points, thus building up the picture.You will also need a vertical imaginary line to assess the distances horizontally, this time with the pencil held horizontally, as shown. Here the line runs down the centre of the near gable end. Once the major lines have been drawn the smaller ones can be assessed easily without resorting to the pencil at arm’s length method.

Once critical points are established, the remaining ones are fairly simple. Begin with the base line – an imaginary line you can easily keep referring to – then create an imaginary vertical reference line to calculate the horizontal distances between points

Farm at Llandegley, watercolour, 8x11in. (20.5x28cm)