Strange artifacts around Alnitak in SII and OIII

Also checked Ha and it is there as well but not as bad

Hi Johan @lanties,

I think you mean the strange squarish diffraction pattern in Alnitak ?

This is, unfortunately, a known problem of the ZWO asi 1600 camera. This occurs due to the specific sensor glass in front of the sensor that is used, it causes reflections. I have the camera myself and I have this as well. I see it on bright stars with long exposures clearly 😐 

Besides that, the data looks great 😋 

Mabula

Hi Mabula @mabula-haverkamp-administrator, 

Thank you for the info and for the compliment on my data.

I already had to throw a full set of ZWO filters away due to terrible halo's and replaced those with Astrodon filters. The expensive learning curve of being very new in this hobby. At least the problem is only with very bright stars.

Regards

Johan

Hi Johan @lanties ,

Yes, this can be a nasty hobby in that sense 😉 ...

Unfortunately the asi1600mm has no good coatings on the mentioned glass in front of the sensor, giving you the square diffraction patterns. I have the first version of the as1600, you too? I don't know if this issue is fixed in the latest asi1600 version. (the PRO one).

Cheers,

Mabula

I Mabula, @mabula-haverkamp-administrator,

I received mine and less than a month later they released the pro version. No offer to swap out or upgrade even at a fee. You can understand there is a bit of frustration here.

The pro version, as far as I know, does not address this problem.  A good friend of mine, here in Cape Town, also have the MM as well as the MC 1600 pro and he has the same diffraction patters with both cameras. His new ZWO filters seems to be better than the ones I had. The diffraction is however more prominent using the ZWO filters than the Astrodon filters.  There seems to be no halos with the new ZWO filters. 

Posted by: lanties

I Mabula, @mabula-haverkamp-administrator,

I received mine and less than a month later they released the pro version. No offer to swap out or upgrade even at a fee. You can understand there is a bit of frustration here.

The pro version, as far as I know, does not address this problem.  A good friend of mine, here in Cape Town, also have the MM as well as the MC 1600 pro and he has the same diffraction patters with both cameras. His new ZWO filters seems to be better than the ones I had. The diffraction is however more prominent using the ZWO filters than the Astrodon filters.  There seems to be no halos with the new ZWO filters. 

Hi @lanties,

Okay, thank you for that information. I was a bit frustrated as well ;-( . I bought the asi-1600 and was a bit disappointed I must admit. The camera is great on everything but bright stars is my conclusion.

Filter can have a big influence as well, that's clear. I was using Baader LRGB filters with the camera, perhaps they were a bad match as well...

Mabula