[avandonk]

I should also say I process my data that shows very dim stuff down to the noise while not saturating the bright stuff. It is called tone mapping. This will also make faint haloes more noticeable. It is all a matter of taste.

If you know anything about diffraction you will realise that at long focal lengths and high focal ratios it is lost in the noise. The spikes produced by secondary vanes being the exception as the edges are straight. There are two sorts of diffraction, Fraunhofer and Fresnel, one far field and one near field. Just Google it. In a complex optic like the RH200 both apply and should be taken into consideration when designing the optic. This can lead to effects not seen in a pure far field situation such as a long focal length refractor or reflector with a simple plane secondary mirror.

A simplistic way to think of it is Fraunhofer with a telescope and Fresnel with a microscope including an electron microscope..

As I said these are test images to give me an idea of what is really happening not a polished final product for general consumption.

All your insights are gratefully accepted.

We are all just slightly evolved apes groping in the dark and hopefully heading for the light!

Bert