The Synth module generates physically correct diffraction and diffusion of point lights (such as stars) in your image, based on a virtual telescope model.
Besides correcting and enhancing the appearance of point lights (such as stars), the Synth module may even be 'abused' for aesthetic purposes to endow stars with diffraction spikes where they originally had none. It is worh notjing that any other tools on the market today simply approximate the visual likeness of such star spikes and 'paint' them on. However the Synth module can physically model and emulate most real optical systems and configurations to obtain a desired result.
Please note that the use of this module on your images falls outside of the realm of documentary photography.
It governs the range of detail sizes HDR should concentrate on, in order to bring out the most detail.
Preset buttons can be distinguished by their icons; they bear the icon of the module you launched.
Even the way StarTools displays and scales images, has been created specifically for astrophotography.
As of 1.7, enhanced mouse controls are implemented; Zoom in.
You can convert everything you see to a format you find convenient. Give it a try!