Astronomiks narrow band filters

[Paul Haese]

After several narrow band images presented with prominent halos I was advised to contact Astronomiks to seek replacements of the defective filters.

I contacted Gerd from Astronomiks with advice from Mike Sidonio. Gerd asked me to present certain information and images and it turns out I had defective filters.

Astronomiks have subsequently replaced those filters for me and I now need to send the old filters back for batch testing.

I just want to say thanks to Astronomiks for being so good about this as I bought the filters nearly 3 years ago and yet still provided a warrantee.

If you want to see what the halos look like click on this link (http://paulhaese.net/ngc6357.html).

[leinad]

That's good. I thought this was more so a glass, light, CCD coverglass effect with the filters, not that they could be defective.
I noticed my Ha Astronomik has halo effects with the FSQ even the luminance which I only got with the QSI last year. Might have to get some data sets done with each and get Gerd's opinion.

If you can post up a NB sample with your new filters that would be great.

[troypiggo]

I went through all this recently (http://www.iceinspace.com.au/forum/showthread.php?t=86869) too. The halos shown here (http://www.iceinspace.com.au/forum/showpost.php?p=831419&postcount=14).

Here is the Astronomik page on the issue (http://www.astronomik.com/en/news/astronomik_halo_free_filter_halo_pr oblem) and how to go about getting it rectified. They were very obliging.

[Poita]

I had the same experience, they replaced the filters, which is great service.

[troypiggo]

Yes, thanks to Peter for point me in the right direction above.

[allan gould]

Had the same experience and they replaced the filters with no hesitation. Great service.

[gregbradley]

Cover glass halos are very small if at all. Probably overhyped as an issue.
Its an antireflection coating issue primarily and a blacken the edges issue secondarily (it affects the flats more than anything).

I have had some older Astronomik filters. I quite liked them apart from the fact that they were only 1mm thick and all the other companies filters were 3mm and most filter wheels were geared up to hold 3mm thick filters. Gerd eventually came out with spacers but not before a few got damaged by getting loose in the filter wheel.

Greg.