Measuring a portrait drawing primarily involves using proportional measurements to ensure the features and sections of the face are in correct relation to each other. One fundamental method focuses on dividing the face vertically into roughly equal thirds.
According to a common technique highlighted in the reference video, you can measure a portrait drawing by comparing the vertical distances between key features:
- The distance from the bottom of the nose (nostrils) to the chin.
- The distance from the bottom of the nose (nostrils) to the base of the brow.
- The height of the whole forehead.
The reference specifically notes, "Now. I can see that the bottom of the nose the nostril through chin is roughly equal to the nostrils to the base of the brow. Which again is equal to the whole forehead." This demonstrates that these three sections should ideally be approximately equal in height for a balanced portrait.
Why Proportional Measurement is Key
Accurate measurement in portraiture isn't about getting exact centimeter readings but about maintaining correct relative sizes and distances. Using proportional methods helps artists:
- Achieve likeness to the subject.
- Ensure facial features are placed in the correct locations.
- Create a balanced and harmonious composition.
Practical Measurement Techniques
Beyond the "thirds" rule, other methods for measuring include:
- Sighting: Using a pencil or stick held at arm's length to measure the relative size of features or distances on your subject (or reference image) and transferring those measurements to your drawing.
- Comparing Widths and Heights: Measuring the width of features (like the eye or the nose) and comparing them to heights or distances between features. For example, the distance between the eyes is often roughly equal to the width of one eye.
- Using Landmarks: Identifying key points on the face (top of head, hairline, brow line, base of nose, mouth line, chin) and measuring the distances between them.
Example: Applying the Thirds Rule
Let's illustrate the vertical thirds measurement using a simple table:
| Facial Section | Description | Ideal Proportion |
|---|---|---|
| Forehead | From hairline (or top of skull) to brow base | Roughly 1/3 |
| Mid-Face | From brow base to base of nose | Roughly 1/3 |
| Lower Face | From base of nose to chin | Roughly 1/3 |
Note: The reference specifically highlights the equality of the mid-face (nostrils to brow base) and lower face (nostrils to chin), and relates these to the forehead, reinforcing the concept of these three sections being roughly equal in a well-proportioned face.
Tips for Measuring
- Always measure from the same viewpoint if working from a subject or reference.
- Check measurements frequently throughout the drawing process.
- Use relative measurements (comparing parts to each other) rather than absolute measurements (like inches or centimeters).
- Don't be afraid to make adjustments based on your measurements.
Mastering proportional measurement is a fundamental skill for creating accurate and compelling portrait drawings.
