Narrow band filters - upside down placement ?

[pawelp]

Hi,

I wonder if this shot's reflection(?) means that my OIII ZWO filter is placed upside down in the filter wheel...

does it look like that from this image below ? (I don;t see the same effect for the Ha and SII filters)

thx for any advice

[david_taurus83]

Oiii filters are renowned for causing halos. You could try turning the filter the other way to see if it helps or adjust spacing between your camera and filter.

[teoria_del_big_bang]

4 minutes ago, david_taurus83 said:

Oiii filters are renowned for causing halos. You could try turning the filter the other way to see if it helps or adjust spacing between your camera and filter.

Yes I have read this on a lot of threads about OIII filters. I think at one time Baader replaced a lot of them so must have been a quality control issue with them as most said the replacements were much improved.

Also on the Baader website somewhere there is a statement that if you have a flattener, coma corrector or reducer to turn the filters round so the arrow points towards the camera if you suffer halos.

unmounted-filters-which-side-should-face-the-telescope

I know your filters are not Baader but the same may be true for other filters as well.

I must admit I have a flattener and my arrows point in the more normally accepted direction to the scope without issues.

Steve

[pawelp]

Thank you. I have a quadruplet. So probably learning some posprocessing techniques to eliminate the OIII halo bias over the other colours assigned to the other filters will be the way to go.

Pawel