An interesting paper I've read recently which I thought worth sharing.

http://www.ejournal.unam.mx/rmf/no511/RMF51116.pdf

Some interesting observations on secondary mirror supports in Newtonian telescopes, and designs for these supports which minimise the diffraction spikes in images of stars.

I've often seen single arm supports and curly supports on commercial scopes, but I've not seen this approach before - although I'm sure it has been tried. I am also sure somebody will point one out to me.

I have reproduced one diagram from the paper here to illustrate their approach.

newtonian telescope support

The reaction of most astrophotographers is one of horror - why should you wish to remove the attractive spikes. Some astrophotographers even add diffraction spikes to the images during processing.

For scientific observations, the large diffraction spikes are very annoying. I've done spectrographs on my telescope and it is very frustrating when a diffraction spike from a star cross the spectrum of a dim object you are trying to measure

From an imaging perspective, I think the interesting "point" is in figure 9c and 9d. As well as removing the gross spike artifacts, the intensity profile of the star appears improved in (d), perhaps giving a better fwhm, i.e. tighter stars and detail. That is of huge interest to astrophotographers.

I am moderately interested in starting a mini-project to try this on my own scope, but I've a few other jobs to get finished first!!