Draw and their Measurements

Then begin darkening a couple of the darkest places in the drawing. Don’t be afraid to go too dark in these areas. It won’t matter. In fact, it will probably help the drawing in the end because it will add contrast. Now we have the basic eye shape in we can then put in the lens of the eye which when looking straight at us is a perfect round shape. Observation is the key here so observe how far away the lens is from the left and right corners of the eye and observe the size and shape of the lens in relation to the whole eye shape. Keep in mind the relationships of the shapes and lines that you draw in and then draw in a little round shape for the pupil.
Look to see where your light source is coming from, it could be coming from above or below or to the right or left or more straight on, here it is coming from above and slightly from the right. Now we can block in some shading over the whole eye shape either with diagonal shading (from right to left) or if you are left handed (from left to right). The actual lens of the eye is quite a bit darker than the whites of the eye around it so good observation of tonal values is needed here, also try to keep a little area clear of shade for the small highlight which in this example is more or less in the centre of the lens.
We now need to draw in the little areas around the eye to set the eye off a little so observation is needed here, shade in these areas with a 2B pencil. Draw in the pupil of the eye which is more or less in the centre of the lens with a dark 4B pencil. The actual eyeball is round so draw in slightly darker shade in the left and right corners of the eyeball to indicate its roundness.
Everything is drawn in darker now building up shade as we go along and we also draw in the eyebrow to set the eye off a little. The top lid is usually darker than the bottom one so we need to observe this if we want to make the eye look like a real eye. There are darker lines around the outline of the lens of the eye which brings the lens out to us more from the eyeball.
Summary
We have finished the drawing. The eye appeared to be darker all around the actual eye shape, and necessary areas are drawn in dark accents. Also don’t forget to leave white paper for the highlight. If you cover up the lights and the highlights with your shading — don’t worry! You can use a putty rubber or bluetac to remove the shading. We used this very method in that case. After all the efforts you’ll get something like this: