A key application of dodging and burning is to improve contrast (tonal reproduction) in film print-making; today this is better known as tone mapping in digital photography – see high dynamic range imaging. The technical issue is that natural scenes have higher dynamic range (ratio of light to dark) than can be captured by film, which in turn is greater than can be reproduced in prints. Compressing this high dynamic range into a print either requires uniformly decreasing contrast (making tones closer together) or carefully printing different parts of an image differently so that each retains the maximum contrast – in this latter dodging and burning is a key tool.