3.9   Stretches: Summary and conclusions

In this chapter of the tutorial you have learnt how to improve the contrast of the Bilko image display by using different contrast stretches.

Having completed the activities in the previous sections you should now understand what is meant by contrast stretching, and how different types of stretches are used to map the image data values to the 0-255 grey-scale values in the 8-bit display window.

You should now be able to use the frequency distribution of the image data to help you choose a suitable stretch for displaying different types of data, and be able to design your own manual stretch based on frequency information.

You should be familiar with the Bilko Stretch Menu, and know how to use it to apply different stretches, change the settings for the automatic stretch options in the stretch menu and redisplay dialog.

Finally you you should know how to save stretch use it to change the display of a series of images in order to make this visually comparable.

In chapter 4 of the tutorial you will learn how to add colour to greyscale images by applying a suitable colour palette, and investigate how palettes interact with contrast stretches to emphasise features of interest in different images.