oleg hat geschrieben:How can I overcome these ghosts?
![Smile :)](./images/smilies/icon_smile.gif)
![Bild](https://lh4.googleusercontent.com/-ROupf2c9qV4/Tz46wmcny6I/AAAAAAAAAMo/M6oxrRf-d48/s299/ghosts.png)
you can't. they are an inherent consequence of the optical design of WFI@MPGESO. in particular narrow-band filters are bad, such as H-alpha, and i guess that is the filter used in the image you are showing us here.
mischa