How to make diffraction spikes ?

[sbechdolt]

This is my first post here. I am beginning to do imaging and I don't know how to make diffraction spikes around stars as so many images show. Is there a simple way I am missing?

Thanks

[toml42]

Get a reflector telescope

but seriously, i understand some astro editing software has a tool for that, someone should be able to give you specifics.

alternately, i imagine you could make real ones by crossing some string in front of the objective.

[RobH]

If you use a scope with a secondary mirror and no corrector plate the vanes holding the secondary will produce them anyway.

If you're using a refractor or SCT / Mak type of scope, then simply stretch some thin cotton over the objective.

Or, there are 2 options from Noel Carboni....

A basic starspikes action is included in his very useful Astronomy Tools....

Astronomy Tools Action Set by ProDigital Software

and a much more flexible version here....

StarSpikes Pro Plugin by ProDigital Software

Cheers

Rob

[toml42]

oh, welcome to sgl by the way!

[ollypenrice]

Funny one, this. Some love 'em, some don't. The software that I'd like would be one that removed them!!

Olly

[sbechdolt]

Thanks for the help here. The software is just what I was looking for. I don't usually want them but once and a while they look great.

Steve

[LukeSkywatcher]

I love spikes in SOME images (The Seven Sisters) and other asterisms. However if your images are widefield with hundreds of stars then spikes can really reduce the viewing pleasure.

PL did a tutorial in S@N some time ago and his top tip was to cover the objective (i think he was using a refrac) with thin cotton or nylon (a pair of the wifes tights should do). Alternatively i think he also suggested "cross hairs" on the objective (2 strands of cotton.........one top to bottom and one left to right).