Squinting is allowed.
Botanical Art & Natural Science Illustration – Drawing Tip #9
Botanical Artists and Natural Science Illustrators are expected to see all the intricate details of their subjects. The more that is seen, more can be recorded. This intense observation is what identifies one species from another. So why would I suggest that squinting is allowed. What a peculiar thing to say when talking about drawing. If the objective is to learn to see, why would I squint? The answer lies in being able to see the difference in tonal values.
Part of creating a botanical or natural science illustration is indeed the details but it is also important to create volume in a drawing. This is done by creating gradations of graphite in many shades of grey. To simplify this look at the levels of these 3 tones;
0%(white), 50% (Medium Grey), 100% (Darkest Grey)
In example #1 the value of the middle square is too light.
By squinting at the squares you should see one dark box and 2 light ones.
In example #2 the value of the middle square is too dark.
By squinting at the squares you should see one light box and 2 dark ones.
In example #3 the value of the middle square is approximately in between the
white and dark box.By squinting at the squares you should see 3 separate values.
When you are doing a drawing and you need to decide if your values are too light or too dark, squint and you should see at least 3 distinct values. If you don't, make the correction. Then, stop squinting and get back to work!