To determine the scale factor of Camilla's drawing, we start with the scale provided:
\[ 4 \text{ inches} = 2 \text{ feet} \]
First, we need to express both quantities in the same unit. Let's convert 2 feet into inches. We know that:
\[ 1 \text{ foot} = 12 \text{ inches} \]
Thus,
\[ 2 \text{ feet} = 2 \times 12 \text{ inches} = 24 \text{ inches} \]
Now, we can rewrite the scale equation:
\[ 4 \text{ inches} = 24 \text{ inches} \]
Next, we set up the scale factor as the ratio of the drawing measurement (in inches) to the actual measurement (in inches):
\[ \text{Scale Factor} = \frac{\text{Drawing measurement}}{\text{Actual measurement}} = \frac{4 \text{ inches}}{24 \text{ inches}} \]
Now, simplify the fraction:
\[ \text{Scale Factor} = \frac{4}{24} = \frac{1}{6} \]
Therefore, the scale factor of the drawing is:
\[ \boxed{\frac{1}{6}} \]