Photographing subjects in open shade can be a challenge. The first picture of the tortoise was taken with natural light in mid-afternoon with very bright spots in the background and very dark areas on the subject.
The next picture was taken with direct flash. The dark areas disappear, but the harsh shadows look like- a flash picture. Not the greatest.
The last picture was taken with a Graslon 4100F diffuser. Notice how natural the subject looks, and the dark areas are nicely lit with soft, even light.