No light, no flash, but lots of action.
Here, a young Coopers hawk enjoys his evening meal before bedtime.
Canon 50D with 500L f4 lens @ 1/500, f4, ISO 800, +2/3 exposure compensation.
Slight crop to remove excess upper and lower background. Because of the evening scene with its low dusk light and overcast sky, I kept sharpening, contrast and noise reduction to a minimum to convey the feeling of the moment. To have used flash, even fill-flash, well . . . I would have an obvious flash image.
Cheers,
Mike