Astra Image is a fully featured application for doing advanced image processing. It is commonly used for astronomical and other scientific images, remote imaging, microscopy, as well as every-day photos. Astra Image combines many powerful features in a single, easy-to-use application. Some of the core features are also available as Adobe Photoshop plug-ins.
Very small details: sets how much the very small details will be sharpened.
Small details: sets how much the small details will be sharpened.
Medium details: sets how much the medium details will be sharpened.
Large details: sets how much the large details will be sharpened.
Very large details: sets how much the very large details will be sharpened.
Halo reduction: sometimes halos will become visible around strong edges and sharp transitions from dark to light. This option tries to remove these halos. It is usually best to set this to its maximum value of 100.
Separation filter: before the image is sharpened, details are separated based on size. The Separation filter option lets you set what kind of filter is used to extract the details. Often, the Lorentzian setting is best as it produces less halos, but other filters may work well with your image and will produce slightly different sharpening effects.