Diffraction Spike Oddity

[Dippus]

Hi peeps.

I decided to make a couple of diffraction spike plates. One for my SCT and one for my 80mm APO , mainly to help with focusing but also to keep them on from time to time as i like the look of spikes.

So i set up an artificial star in the workshop to test one out with the APO. 3 nice spikes , but one crazy long one.... Any suggestions why? Maybe the optical train isnt quite straight ....Dunno

I would like to solve this problem .... Crucifixes make me nervy.

Thanks Mark

[steppenwolf]

This is a 'blooming spike' caused by the very bright image optically 'leaking' into the vertical registers during CCD readout.

[Dippus]

Thanks for that Steve . Will google blooming spike and have a good read. Cheers for pointing me in the right direction.

Mark