First Light new scope

Hi John,

This is exactly the problem that I mentioned to Aubrey in another thread. It is the different sizes of the stars from the different filters - gives this edge colour that you see. The magenta colour is very well known side effect and somewhere along the way, I have picked up a small process (PixInsight only) - that tackles this problem. I downloaded your image - took it into PixInsight and just quickly run the process.....two seconds only....and this is how it changed the image:






If you use PixInsight, I can pass this little process to you no problem. (Or to anyone else that wants it....)

You may still need to work on the stars again after using the process....it only takes away the magenta.....the 'halo' effect is still there on the bigger stars......and that is something I need to work more on myself too! It can be very frustrating but rewarding also (eventually) - hope you are enjoying testing out the new scope

Brendan

Thanks Brendan. That really took out the coloured halos. I don't have PixInsight, I use MaximDL and Photoshop CS6. I must check out Noel Carboni Actions for Photoshop and try them for small halos. I have been tempted for a while to try PixInsight but don't know if the new software learning curve effort vs the benefit is justified. I should try out the free trial.

The Halos on the bigger stars on the O111 filter image took me by surprise (see O111 image below, focus could be better). I was disappointed to see any halos using the new scope and flattener. The halo's only appear on the O111 filter. I contacted Baader and they asked me to check it out again as the reflections may be down to other factors besides the filter. I know that the Baader O111 filters were on a product recall in 2015 and I was wondering if mine were faulty. However I will check it out again.

John

I know that a couple of years ago I had a bad halo problem with an Astronomik Ha filter. It was a known problem and Astronomik replaced the filter for me. It did not cure the problem - but it did lessen it. I think if possible - it would be a good idea to check the actual filter you are using against some other. Perhaps someone in Dublin (reading this) may be able to help you out with the loan of another filter - just to do a test. What size filters do you use? If it is 2" - I can loan you a Astronomik OIII filter to see if it would produce a better result. If you can say for definite that it is the filter - then you have a case to get Baader to change it.

In the meantime, you can reduce the effects - but it is a lot of work to fix it with software. For sure - getting rid of the magenta hue should not be a big problem with Photoshop - just reduce the magenta colour saturation adjustment to -100. That will 'almost' do exactly what I did in PixInsight. Reducing the halo itself is beyond my capabilities in PS - I don't know or use the programme very much.

I hope that you can find a solution within a reasonable time - these things can be so frustrating. (Don't forget to let me know if the 2" Astronomik filter is of any use......if yes I can put it in the post to you on Monday).

Brendan.

I can't believe I just deleted my last message on the board here - hope someone got it by email and can paste it back in here.....please do if you can.
(John - bottom line on my last post was to say that I can loan you a 2" Astronomik OIII if that will fit your set-up; just to do a test).

I have seen the recall notice from Baader....it has a number quoted......so if yours is in the batch then you have grounds to change it.

QUOTE:

RETURN ANNOUNCEMENT for Baader 11⁄4" O-III 8,5nm CCD Narrowband Filter (#2458435)
October 2015

Baader Planetarium has been manufacturing astronomical filters for more than 25 years. Apparently for the first time ever, a number of 11⁄4 " OIII-CCD-filters HBW 8.5 nm (item no 2458435) has gone through QC without it being noticed that some filters of that run produce halos on bright stars. All filters in stock have now been tested 100 % and it is obvious that about 10 % of the 11⁄4" OIII filters showed this condition. No other production run of 31.7mm or other sizes of OIII filters, or any other filter type or sizes have experienced this issue. We deeply regret this error.

Regularly our QC checks about 50 % of the production qty. Due to this finding we have increased QC to 100 % and can positively rule out that any more filters with halos can go out the door.

For anyone who has been delivered a #2458435 Baader OIII 11⁄4" CCD-filter within 2014 or 2015 (as single filter or in a filter set) which gives a noticeable halo around bright objects, we ask them to please contact us (kontakt@baader- planetarium.de) or your local / national distributor and send an image made with that filter, together with a proof of payment. We will then immediately send a new filter directly to this customer in order to keep our customers and dealers unharmed from extra freight charges. It is a matter of honor to retire the faulty filters after we have sent an exchange (please dispose of the faulty filter as soon as you receive the replacement). Hence we make this announcement as quickly and openly as we can, to reach everyone well before the end of this year so that we have a chance to send replacements also all within this year.

We absolutely do beg our customers and dealers for pardon for this failure in production and QC, for the loss of time and for the loss of good nights under the stars. Next year we are heading into our 50th year of supplying the Astro- community. Anyone using a Baader-product knows how hard we have tried throughout all of these years to please our customers and to design products without planned obsolescence. It is our pleasure to correct this failure and to ensure you that we will keep on doing this whenever we make an error. We are all human, but we stand behind our products 100%.

Thomas Baader

Thanks Brendan for the great advice and I appreciate the generous offer. I already have a Astronomik 1.25" O111 12nm filter and I will try that whenever the clouds disappear (sigh). Baader have expressed their willingness to change the filter but in the meantime suggested (a) that I remove the Flattener and see if the Halo is still visible and (b) that I turn the filter around so that the front side is not facing the light source to check if there is back scattering inside the telescope. They also referred me to this site which was interesting:
web.archive.org/web/20140729003031/http:...s_release:391,355,49

Despite all of this I will be asking Baader to send me a new filter as they promised in their product recall.
Even though it can be frustrating there is always a little more learning in this hobby. Thanks again for the help.
John

OK John.......perhaps you got my last post via email.....that is how I receive posts other than my own.
Whatever way it goes......sure hope you get it sorted. Best of luck with that.

Brendan.