IC1805 with Askar Duo-Band Filter

[Budgie1]

I finally got a clear night! Still had the Moon to deal with later on but it was the first change to image since 21st November. 

In the FLO Black Friday Sale I got a 2" Askar Duo-Band filter at a reasonable price and this was the first light with it attached to my Evostar ED80 and ASI294MC Pro. I wanted to see how it compares to my 1.25" L-eXtreme and it seems to work quite well, still very early days yet.

This is 5 hours 20 minutes of 240s subs, stacked in DSS with Darks, Flats & Dark-Flats and processed in PI. There was quite a bit of wind last night so guiding could have been better, but there were no bloated stars or any signs of halos around them, so I'm pleased with the filter so far. 

C's & C's welcomed.

[scotty38]

Very nice. I've only imaged IC1396 since I received my L-eXtreme but on that target I get significant halos around the two brightest stars. When I get chance I should give this one a go to see if I have a poorer filter or if it's target dependent.....

[Budgie1]

6 hours ago, scotty38 said:

Very nice. I've only imaged IC1396 since I received my L-eXtreme but on that target I get significant halos around the two brightest stars. When I get chance I should give this one a go to see if I have a poorer filter or if it's target dependent.....

For the stars in this image, I used a slightly different way to reduce them.

Normally I just use MorphologicalTransformation set at 0.3 (30%). On this image that did reduce the stars in size & brightness but left them looking more like smudged dots on the image. So, as well as 30% reduction, I also gave one instance of Deconvolution at default settings. This sharpened the reduced stars and I think it gives a much better final image.

If it's of any help as a comparision, here's my last effort with IC1396 in late August, using the 1.25" L-eXtreme filter on the ASI294MC Pro.

[scotty38]

Thanks for that. much appreciated.

Here's mine with nothing but an STF stretch:

 

[Richard_]

Lovely image Budgie!

I also use the L-extreme filter and aren't overly happy with the halos on brighter stars. My IC1396 has a halo on exactly the same star as @scotty38's in the lower left corner. I'll be looking into the Askar duo band filter, along with the new Antlia gold duo bandpass filter and see which one would be a better replacement. 

 

[scotty38]

3 minutes ago, Richard_ said:

Lovely image Budgie!

I also use the L-extreme filter and aren't overly happy with the halos on brighter stars. My IC1396 has a halo on exactly the same star as @scotty38's in the lower left corner. I'll be looking into the Askar duo band filter, along with the new Antlia gold duo bandpass filter and see which one would be a better replacement. 

 

Thanks for that... Bad news but at least it's not just me.. 🙂

[Richard_]

15 minutes ago, scotty38 said:

Thanks for that... Bad news but at least it's not just me.. 🙂

Here's the processed picture in question, 7hrs with l-extreme filter. I wasn't happy with this attempt, due to the background colour and the large halo, so I never posted it here and I haven't attempted a reprocess yet. I have recently put together a better process workflow on my Heart Nebula image, so I may repeat that for this image to see if the halo is reduced. 

From what I've read, the halos are a common problem for the l-extreme, so I don't think it's a "one off" quality problem. 

To keep this on topic, @Budgie1, it would be good to see a comparable image of this target with your Askar filter to see if you also get halos or not. Do you happen to know what the bandpass is for the filter? 

Edited December 29, 2021 by Richard_

[Budgie1]

1 hour ago, Richard_ said:

To keep this on topic, @Budgie1, it would be good to see a comparable image of this target with your Askar filter to see if you also get halos or not. Do you happen to know what the bandpass is for the filter?

I'll see what I can do with imaging IC1396 again but with the Askar filter.

The filter is also a 7nm pass, same as the L-eXtreme, so they should be similar performance. I got this one because I had the L-eXtreme but it's the 1.25" version and wanted to start using the ZWO Filter Draw, so needed the 2" filters for that. I already had a 2" UV/IR Cut filter and then 2" Askar Duo-Band came up in the FLO sale with a good reduction.

I managed to get another 2 hours imaging on the Bubble & M52 last night and it is showing halos around some stars but I managed to remove it in post processing by reducing the saturation on the stars, once they're removed from the background. The halo is still there on some of the brighter stars but the colour reduction has made it less noticeable.

This is the image with only a STF stretch applied by PixInsight, so you can see the halos as they come out of the camera.

 

Edited December 29, 2021 by Budgie1
Added image.