Antlia Ha 3nm HALO :(

[Emuhead]

My first sub with these filters.. Ha 3nm filter.. Halo shown.

This is a mag 3.8 star belonging to the Dolphin Head nebula. SH2-308

I was using an f/3 reducer, and ive heard the faster the optics the more likely a halo can occur. There were no halos on the Oiii 3nm filter, which is interesting.

Very very sad face.

[AdamJL]

You raised the issue…fast f/ratios can do it. You could always try exchanging it to see if you can get a better copy. That said, halos with these filters are rare, so you could have some luck exchanging it.

Or sadly, pony up for the Chromas…

[AnakChan]

Did you try flipping the Ha over? (i.e. got the correct side facing the camera vs the OTA)?

[Emuhead]

All i do i pony up.. this hobby takes you to all new levels of wallet opening. Im on the exchange track, hopefully that comes through.





I looked into that, super reflective side without double reflections to the sky & the side with the double reflections pointing to the sensor, so its not that but could try flipping it anyway.. see what happens.

[Emuhead]

The reflection is only 3.6mm from the sensor, so the 2600MM window, which leads me to think its tilt related. Aiming to address tilt, try a different reducer, and see the outcome of that.