Evostar 120 filter

[stickbow]

Hi all

I have just got an Evostar 120 refractor and when I look at Jupiter is has a purple tinge around it, I was told this is CA and you can get filters to filter this out, anybody know the best filter to use for this.

Cheers..

[rwilkey]

Hi Stickbow, the Baader Semi-APO filter will do this for you, here: http://www.firstlightoptics.com/achromat-semi-apo-filters/baader-semi-apo-filter.html

[John]

The filter will reduce the CA by around 40-50% but it won't rid you of it completely.

[Bizibilder]

You may find you can improve the image (ie reduce the apparent CA) simply by increasing the magnification.  Theoretically all wrong but it works!