Skipper Billy

33 minutes ago, Stuart1971 said:

What do you get on images with no filter or just a plain glass filter ??

No problem with any other filters apart from Oiii and Blue - I am fairly convinced that the issue is with the filters and Baader are looking into it for me. Meantime I am just making sure that all other possibilities are explored whilst the rig is in bits and spread across the dining room table! 🙂 

4 minutes ago, Stuart1971 said:

If it was that, it would show on all filters and not just one of them…but still a good idea to cover, or swap them out one  at a time for Black headed ones..

True but I think i read somewhere (Vlaiv?) that Blue light and Oiii are more easily scattered than all the other wavelengths???

Cant do any harm so black insulation tape and sharp scissors required 🙂 

I have carefully inspected the entire optical train with a really bright torch looking for anything that is reflective.

The only thing I can see that is reflective are the screws that hold the camera together - see attached. (The inside of the scope is beautifully baffled and darker than a coal hole!)

Is it possible that light is passing through the filter hitting the screw heads and bouncing off the back of the filter into the camera causing the halos???

I am toying with the idea of making a mask to cover the screw heads from stiff black card and sandwiching it between the filter wheel and the camera.

Cracking image. Lucky you with the clear nights and you are just up the road from me!  Well done. 

1 hour ago, AstroGS said:

It is not a highjack - it is a nice warming conversation of two friends sharing the same love for the cosmos as, it would have happen if we were all together at a star party.

What a lovely and refreshing attitude ! 🙂 

26 minutes ago, assouptro said:

Hi Dave 

I have the full set of 2” Antlia filters and so far I have been impressed 

No significant halos to be seen 

After being burned by other brands and investing in a full set of 1.25 Astrodon filters I was worried buying the Antlia filters as it was still a significant investment for the 2” versions 

I opted for the 4.5hd edge version as I had recently bought a Sharpstar 15028hnt reflector that I have yet to use in anger but with my “slower” optics so far I haven’t been disappointed 

Hope you are well? 

Thanks Bryan that restores my confidence a little!

I am well - now - I had a new Aorta and femoral arteries a few weeks ago but I am well on the mend now.

20 minutes ago, AstroGS said:

Thank you - I will try to push a bit more the stretch to see if I can get a bit more of the dust.

I have spent years trying to develop a lighter touch to my processing and I think you nailed it in your original. I wouldnt stretch it much at all. The web is full of grossly overprocessed almost comical images with blown highlights !! Jewellers dont put their goods on a market stall ! 🙂 

28 minutes ago, Stuart1971 said:

Hmmm, yes they are pretty bad, and also more worrying is the halos are off centre too, which only  normally happens at the out edges of the image, would not expect this at all with a Tak106…

Yep - I am not a happy bunny at the moment!

Anyway - I won't hijack your thread - cracking image by the way - just shows that there is no substitute for plenty of exposure time !

18 minutes ago, Stuart1971 said:

Do you use a flattener or reducer in your imaging train..? If so one thing to try is to put the filters on the telescope side of that, and you may find the reflections will be diminished..👍🏻

Nope - no reducer or flattener. This is a very heavy crop - maybe less than 10% of the whole image using the Blue filter - the Oiii is just the same.

6 hours ago, AstroGS said:

Over 24 hours of data were collected, with the focus on revealing the nebula's full colours in SHO. However, a setback occurred as nearly 7 hours of OIII-filtered data proved unusable due to unexpected halos and star bloating. Despite efforts during the image processing phase, the OIII data remained unusable. FLO and Antlia are investigating the issue for me.

I wish I hadn't read that! I am having issues with my Baader Blue & Oiii filters and was considering a set of Antlia 2" filters as a fix!

29 minutes ago, saac said:

I'm waiting for a live feed of the end of the world. Should be exciting to watch.

Do you not watch the news? I think it's underway!! 🙂 

More testing of various images in the claculator and spending more time on it than I could at work shows the problem lies between 2.5mm and 4mm in front of the sensor. Given that the distance from the sensor to the mounting threads is ~19mm then the issue must lie within the camera.

Just had a quick play with the calculator and it is telling me that the issue exists 2.5mm in front of the sensor! So NOT a filter issue??

The plot thickens!

On 11/02/2024 at 13:57, Sp@ce_d said:

I got a set of Antlia LRGB & 3nm NB after the ridiculous Astrodon & Chroma price increases and I’m very happy with them. Certainly the NB’s seem to perform as well as my smaller Astrodons & not seen any issues with LRGB so far. 
 

I don’t have any blue/OIII in 2” otherwise I’d offer you a loan of them too.

Thanks very much.

Thats more good things being said about Antlia !

When I get to the bottom of this issue I will post the findings in case anyone else has a similar issue.

All the best.

David (aka Skipper Billy)

On 10/02/2024 at 17:39, symmetal said:

@Skipper Billy Hope you're enjoying your time in Sweden. 🙂 You're welcome to borrow my Astronomik Blue filter try, to see if it fixes your problem. I use the narrowband filters on the RASA but if I need RGB I put on the OSC camera as it's quicker, so the RGB filters are not really being used at the moment.

Thanks Alan

That is an extraordinarily kind offer - thank you.

I am going to live with it until the rig gets dismantled in about 4 weeks time and just check the basics again as its taken apart. and see if I can locate any obvious problems first and if the calculator shows that the filter is the issue then I will probably contact Baader first to see if they have anything to say - its a long shot but worth an email.

Sweden was great - as usual - its a long way to go to see the grandkids - especially via Frankfurt!!

All the best

David (aka Skipper Billy)

I am on my way to the airport now - visiting our grandkids in Sweden - and will have limted comms for the next few days. So I apologise in advance if people are taking valuable time to respond and I am not replying/acknowledging in a timely fashion.

6 minutes ago, Laurin Dave said:

Hi David.. a couple of thoughts...  I'd suggest you try the Blue filter with a different camera eg your lodestar and see if the halos are still present,    also have you used the calculator on  astronomy.tools  to check where they are coming from..   When I got my SX46 (also KAF16200)  it had horrible halos and microlensing like an ASI1600 ...   SX had put the sensor window in the  wrong way around, easily fixed and lucky for me they are only just down the road.   If it is the Blue filter I'd have thought that Baader could supply a replacement, even if you have to pay for it it'll be a lot cheaper than a new set.   As for the Oiii ... the Antlias get good reviews and from what I've seen good results.

Thanks Dave

The Atik16200 is bolted directly to the EFW3 so mounting the Lodestar would be a major faff. But maybe a full strip down and investigation may be required over the summer so that coule be an option. Or I could borrow the ZWO 178 out of my all sky camera.

That calculator looks interesting I will certainly have a play with that. I was unaware that such a thing existed!

Thanks again for your helpful suggestions.

David

1 hour ago, ollypenrice said:

So what's left? Bad batch, certainly.

Have you tried these filters with another camera? A quick search on the 16200 produced a quote from Takman on here: There is still that classic microlensing ‘cross/star’ effect on the bright stars (like the KAF8300, but not as prominent I feel...)  I realize that this isn't the effect you're seeing but I wonder if it might be arising from the camera. The chip glass, the microlenses, whatever. Is there anything else in the optical path? I also wonder if there might be an internal reflection visible only in the blue which is, of course, the easiest wavelength to scatter.

A separate post on halos with the 16200 might be useful.

I dont have another camera sadly but it doesnt do it with any of the other filters (except Oiii which is equally as bad). I have got used to the tiny cross/star effect which is down to the camera and I actually quite like it now! There is nothing else in the optical path. 

Its nearly time to break the rig down now for the summer and will probably contact Baader to see what they say. 

I really dont want to splash out on a new set of filters to find out that the problem still exists and is therefore the result of some other cause!

Thanks again for your help.

Pretty Pictures = just playing at it!!! 🙂 

11 hours ago, symmetal said:

Here are my results using Astronomik filters on the FLT-98 from a few years ago. They are using the full frame ASI6200MM which the FLT-98 can't fully correct so the corners aren't too good. 🙂 These are the raw stack outputs given an STF in PI.

Thanks Alan

Thats very interesting and thank you for going to so much effort.

Its looking like I have a 'Friday afternoon' filter or two !

David (aka Skipper Billy)

25 minutes ago, Xilman said:

What do you want to do? Pretty pictures or photometry?

Pretty pictures! Sans halos !

25 minutes ago, ollypenrice said:

Something is wrong. Clutching at straws, are you sure that's the blue filter? It looks very like the result I got with Baader and Astronomik OIII. You couldn't have a misplaced filter or a confused filter wheel?  Is the filter the right way round? Or, at least, have you tried reversing it?

Thanks for your input Olly.

It is definitely the blue filter and it can only go in the EFW3 one way as its a mounted filter. The Oiii gives very similar results. I dont think Baader will be interested - the narrowband and broadband sets are about 7 years old. This is the second blue and Oiii I have had - the first set were just as bad and FLO swapped them but these aren't much better. I assumed it was because they were relatively budget end filters. Maybe it was a dodgy batch !

I currently use Baader 2" filters for LRGB and Ha Sii and Oiii.

The Blue filter gives horrible halos on bright stars and so does the Oiii

I realise that they are entry level filters and I have decided to bite the bullet and upgrade.

First question is - is there any advantage in upgrading them all or just the two that dont play nicely??

Second question - what brand to upgrade to in a 2" mounted filter??? (I really dont want to have to change my filter wheel).

I feel that the filters are letting the rest of my rig down and I dont mind investing in quality gear but wanted to consult the group before giving my flexible friend a work-out!

Attached image is heavily cropped and uses the Blue filter.

49 minutes ago, Sp@ce_d said:

Great to see you back in action. That definitely looks like a worthwhile target to pursue.. earthquakes aside! 

Cheers!!

21 minutes ago, AKB said:

Really??  Not on my current list of problems!  Sinking into gravel and silt more likely here.

Yes really! One of them was 3.3 mag and cracked a wall !

Last night was a bit of a write-off. Guiding was all over the place and turned out to be a combination of polar alignment having shifted (5 earthquakes in a week) and very whispy high cloud. Then the cloud really rolled in so I only managed to get about 45 mins on the blue channel and no red or green. I was imaging a new target (for me) the Dreyer's Nebula - IC2169 - which it seems is rarely imaged. I decided to process the feeble data I did get and this is the result - just 9 x 300 second subs in the Blue channel. It looks like its worth pursuing when conditions allow. This is just stacked and stretched - no processing. (I need a new Blue filter - it always gives horrible halos on the big stars on the Blue channel - (hello is that Mr Astrodon - I have a kidney for sale!!)

masterLight_BIN-1_4499x3599_EXPOSURE-300.00s_FILTER-Blue_mono.tif