Dragons from Paddy in Bris Vegas

[Slawomir]

Ahoy Comrades!

Taking advantage of a pretty good weather and school holidays, I was able to put together a new image - the first one with my new telescope. Happy days!

Some technical info:
Scope: CFF 105mm f/6 with a 0.75 Riccardi reducer (imaging at f/4.5)
Camera: QSI 690
Filters: 3nm Astrodon
Exposure: Ha - 195 min, OIII - 420 min, SII - 420 min
Colour palette: SHO
Processing: PixInsight 1.8

Signal in OIII and SII was quite weak; I was getting about 3 photons per pixel per minute in the brightest areas with OIII, with SII being somewhat weaker still.

There is some field curvature in the corners so my next image will be at native f/6 with just a flattener to further test the new telescope. I am starting to appreciate the 3.2" FT motorised focuser - solid as a rock and wonderful precision. As for the optics in the new scope - I have immediately noticed some welcomed improvements over my previous beautiful and trusty TS ED doublet - with CFF there was only very minimal focus shift between OIII and SII filters and virtually no halos around stars, but frequent refocus was needed at F/4.5. After trying f/4.5, I look forward to imaging at native f/6.


Link to Astrobin image: http://www.astrobin.com/full/301936/D/?nc=user

Full res: http://cdn.astrobin.com/images/thumbs/ef24147a47f188486ba5ec1ee5730542.16 536x16536_q100_watermark_watermark_ opacity-15_watermark_position-6_watermark_size-S_watermark_text-Copyright%20Slawomir%20Lipinski.jpg

Version with Ha+OIII+SII=LUM: http://www.astrobin.com/full/301936/E/?nc=user

Thank you for looking :)

[SimmoW]

Congrats Slawomir, looks a very good early result! Nice colours too

[SimmoW]

Oh your IIS image seems cropped?

[alpal]

Hi Suavi,
wow - that looks so polished & professional.
Well done.

cheers
Allan

[Slawomir]

Glad you like it Simon. I sometimes just attach a crop to IIS posts because of a 200kB file size limit, but trying to remember to provide links to a full res on Astrobin :)



Thank you Allan for your encouragement :thumbsup:

[DJScotty]

Looks very nice Suavi.

That's a nice piece of glass you have there!

Scott

[Slawomir]

Thank you Scott :)

I have noticed that the image looks quite dark on my iPad, but looks okay on my PC :question:

[Stevec35]

Seems a little dark on my PC Suavi but the colour and resolution look great.

Cheers

Steve

[Slawomir]

Thank you Steve, I made the image a tad brighter.

[RickS]

Great looking image, Suavi! Congrats on the first light.

[topheart]

Hi Suavi,
That is very very good.
Congratulations!

Cheers,
Tim

[gregbradley]

That is a very vibrant 6188, I am mightily impressed.
Congrats on a super successful first light.

Greg.

[strongmanmike]

Niiice shot Suavi, of a magnificent...perennial...imaged ad nauseum :rolleyes:....yaaaawn :zzz2: Object :lol:

Juuust kidding :D looks really great! and well done in shaking down the new kit :thumbsup: (perfect object for doing this ;)) Looks to be performing very nicely...be my turn soon :scared2: :scared:

Mike

[Slawomir]

Thank you Rick, it's good to be imaging again :)



Thank you Tim.



Thank you Greg for your encouragement. It was a bit of a challenge to bring vibrancy to this image due to a weaker SII and not so great SNR in OIII, possibly due to occasional cloud passing when I was collecting OIII and of course proximity to the city.



I look forward to your mega wide field image of this area Mike. I would like to more distinctly highlight hot SII and OIII regions, but with my rig and being close to the CBD, I would need to expose OIII six times longer than Ha, and SII probably about eight times longer to get a similar SNR to Ha. So there is a challenge for you Mike :lol:

[marc4darkskies]

Rich and compelling colour and composition Suavi! Beautiful shot! :thumbsup:

[Placidus]

Superb! Beautiful colour and contrast. Even the very darkest parts are smooth and well defined.

[atalas]

Awesome Sauvi:thumbsup::thumbsup::thumbsup:

[lazjen]

Nice image.

What process did you use in PI to combine the channels?

[Retrograde]

That's stunning Suavi. :thumbsup:

[Atmos]

Fantastic first light Suavi!
Love the detail and contrast, brings a nice 3D feel to the image :)

[Octane]

I can't think of a better object to open the account of your new telescope than NGC 6188.

Well done, mate! You've inspired me to go back and finish my one off from last year!

H

[Slawomir]

Thank you gents for your awesome feedback.

For combining channels I simply used LRGB combination, with Ha being Lum. I was hoping to add at least OIII to Lum, but it has way too much noise with just 7hrs of integration, so I just used straight Ha for Lum.

[RickS]

Hi Suavi,

If you combine the Ha, Oiii and Sii using ImageIntegration (noise-weighted, no rejection) you should get a SNR improvement and also a contribution to the Lum from the other filters, though it may be small if those masters are very noisy compared to the Ha. Worth a try if you haven't attempted it before.

Cheers,
Rick.

[Slawomir]

Great advice, thank you Rick. I will certainly try it.

Signal in OIII is around 300 ADUs above the floor in the brightest areas, while SII is only about 250 ADUs in the same regions, while Ha is nearly 2000ADUs (Gain =0.16). I would also like to try making RGBish stars from narrowband data I have. Will report soon, I hope :-)

[Slawomir]

Given that my camera decided to fog up (first time for me!), I am out of action tonight, or so it seems!

Tried Rick's advice of using Image Integration to combine all subs and it works wonderfully, at least I believe it does :)

I have attached three screen shots of different areas in the Lum image. The one on the left is a result of ImageIntegration (Ha+OIII+SII) without pixel rejection, the middle one is with rejection (love those planes and satellites!), and the one on the right is just Ha that I originally used for Lum (but not drizzled).

I also selected a small section in all three and measured StDev. In all cases, for the combined subs (HA+OIII+SII), StDev was about half of what I was getting in Ha only.

Me think it's time to reprocess my image...thank you Rick! :thumbsup:

[mountainjoo]

Nice and sharp with tiny stars, Suavi. You've shown some really nice structure underneath the dragons.

[traveller]

That's an excellent effort Suavi,
The colour, the detail and the mood, just fantastic!
Bo

[Slawomir]

Thank you Jerome and Bo for your encouragement :hi:

I am in the process of re-doing the image following on Rick's advice.

Left: the original image
Right: The new HAOIIISII Lum version

Looks quite nice I think :-)

New version of the Dragons - I tried to keep colours the same but hopefully there is a tad more detail in the new revision with HA+OIII+SII=LUM

http://www.astrobin.com/full/301936/E/?nc=user

[Raydar]

Beautiful region Slawomir. I like the way you have captured that background nebulosity as well (upper left). I think that background shows the vastness of the nebula.

Ray

[Camelopardalis]

Sensational Suavi :thumbsup:

[Slawomir]

Thank you Ray and Dunk for such kind feedback. I was hoping for more data but this will have to do for now. Perhaps next year I could add more :question:

[Spookyer]

Great start for new scope.

[Atmos]

Prefer the slightly redder new version :)

[Slawomir]

Thank you Brett. As I am gaining more experience with using this scope, I like it more and more. My next image will be at f/6 with a dedicated flattener. It generates perfectly flat field and round stars to the corners, and it won't require as frequent refocusing as imaging at f/4.5 with Riccardi reducer. With the Riccardi I must refocus every 1 degree.



Me too :) I have been tweaking colours a few times since I produced this latest revision, but somehow I keep coming back to this one. It's a sign to move onto a new project.

[codemonkey]

Image is looking great, Suavi!

If I might chime in regarding "super-lum" combination; it's worth trying to integrate all Ha subs into one master (with rejection), all SII into another master (also with rejection), same for OIII. Then using those masters, integrate them using ImageIntegration with no rejection. This gets rid of satellite trails and FPN (if you've dithered), while giving you a higher SNR "super-lum" master in the end. I think this is what Rick was suggesting, but I think from your post above you simply integrated all the subs together.

You might want to play around with noise-weighted vs "don't care (all weights = 1)" as well. Noise-weighted will heavily favour Ha in most integrations, giving you a lower noise image but without much of the detail from SII / OIII, while "all weights = 1" will bring in more of the detail from the others at the expense of more noise.

You could also play around with PixelMath to integrate the masters easily with a higher degree of flexibility regarding the weighting.

[Atmos]

"(Ha+OIII+SII)/3" in PixelMath is a non weighted average integration :P

[RobC]

Great Image Suavi. Congratulations.

Rob

[Slawomir]

Glad you like the image Rob :)

Thank you Lee and Colin for your very good suggestions :thumbsup:

Initially, when putting the data together for the first time, I did exactly what Colin recommended. However, OIII and SII masters were/are very noisy comparing to Ha (signal was 6 and 8 times weaker respectively, and OIII had the highest noise). Thus combining the masters did make the Lum image significantly more noisy, so I decided against this method. In fact, I tried adding noise-reduced OIII and SII and I still felt that the result was inferior.

Using image integration for all subs somehow increased detail in the Lum, perhaps because I had only 13 Ha subs and 56 subs for OIII and SII altogether (no somos machos pero somos muchos).

The final image (revision E) is a blend of 50% Revision D (Ha Lum) and 50% Revision X (Lum=Image integration on all subs).

[RobF]

Simply outstanding image Sauvi. I'm particularly impressed how far you can zoom into the full res and more and more detail comes out - almost like what you expect from a mosaic.

I guess we're seeing the benefits of lots of data, great tracking (and optics), careful processing including drizzle to give an effectively 2x2 larger image.

Whatever, its simply inspiring stuff to see an 8300 sensor in the burbs performing this well. (I like it by the way :D)

[Slawomir]

Thank you Rob for such kind and encouraging feedback. I have a camera with ICX814, however, KAF8300 would be very nice too :thumbsup:

[RobF]

Thanks for clarifying - was getting over confident in my abilities to know the QSI models it would seem. Nice work, putting that Sony QE to good use.

[xelasnave]

I don't comment here because there are so many wonderful images and frankly I am not qualified to do so but this time I feel driven to offer my praise.
I find your images wonderful.
Alex

[IanP]

Sławek - niesamowite
:party2:

[AMG]

Brilliant image.

[Slawomir]

Thank you Alex, Ian and Nathaniel for such encouraging feedback; it really motivates me to try harder (=increase integration) with my next attempt at imaging a piece of the night-sky :)

Dziękuję!

[Ryderscope]

Nice one Suavi. We seem to have dragons everywhere at the moment (including my upside down ones :D)

[Slawomir]

Thank you Rodney. Yes, it must be annual hatching season for dragons ;)

Mine apparently somehow got onto CFF's homepage :)

[strongmanmike]

It did indeed! Nice...

:thumbsup:

Mike

[willik]

Tex book Beautiful image well done
Martin

[Slawomir]

Glad you like it Martin :)