GiorgioF

Hi to everybody.

Lately busy or bad weather. All keep me far from the sky.

Experimenting with a Nikon lens (80-200; 2.8) I tried to catch some photon in a rare clear night.

The camera is a ASI1600 and got 2 hours total in light of 180" of Halpha + O3 installed on a EQ5mount.

This is the first image with that setup. Integration could be longer and elaboration in PI could be better but I feel quite satisfied anyway asTiziana approved.

Will be my pleasure to get comments and suggestion.

20 hours ago, Singlin said:

Is their a website where I can see different narrowband colour combinations with mixing percentages?

Other than what in PM, you can use the PI script I mentioned (SHO script). You can see it in real time.

Great Simon! 

May I suggest you another try?

In ps the "selected color correction" can help to clean and boost the red. The window of the function has a drop down menu. On "Red" you can lower the amount of cyan through the slider near by. With the real time preview you can appreciate the modification. 

Uuuuuuuh.... Really a superb image!

I try this subject days ago with limited success due to cloud.

Able to gather only one hour total, poor data and not satisfied.

You rendered the nebulosity with a light and delicate hand without sacrifice details.

Each one give his own interpretation in the image elaboration with narrowband, sometimes going out of the "classic" combination. I like to think I'm not doing scientific report with my image. I simply can't.

In answering to the question, what bring out details is usually the luminance.

So, once combined and optimized the NB image, it can be extract the luminance from.

This luminance, if needed with a small "cleaning", is then used to emphasize the NB image adding the (!) Luminance part.

Another way with the H and O files is to combine them in a mix that depend on what you have imaged.

Adding the pure H data as luminance it can not show all the details, especially if the subject is rich in O3. So a mix of them in a percentage that can vary, is a good choice.

I feel comfortable using the SHO script of Pixinsight (can be found in PI forum). It allows more control.

And last, I will never stop to thanks Luca, an Italian guy living in US for teaching me what above.

Another small note is the noise reduction that I use. You can search for the "Jon rista method". Jin is a great photographer and experienced in astrophoto. 

...a marvel...., a dream....

I like more the wide field than the crop.

It is more smooth and give a wonderful eyesight of the area

7 hours ago, Singlin said:

Wow ! that is fantastic.

Can you jot down your workflow so that I can try and understand how to improve?

Thaks so much.

Regards,

Simon

What software are you using?

Love it???

Yes, a lot! As you said, more data, not only Ha but also O3. It really deserve!

That will be my next target.

On 21/08/2019 at 15:50, Singlin said:

Here is a link to my Ha,OII and SII data.

I would be pleased for others to see what they can do so that I can learn from it.

https://www.dropbox.com/s/dv1i2lklxmf87qz/NGC 6888.zip?dl=0

Dear Singlin, I hope you don't mind if I take few minutes to play with your data.

They are really good shots but already in non linear state. This means some result could be better if the job start from the raw data, just stacked.

Anyway, this is my personal interpretation for which I than you for the opportunity.

Process was quick and dirty in PI, as said.

Linear fit of the three frames over the O3, combination in HSO. Add the Ha as luminance (thank you Luca for the hint).

Some denoise, a small stars reduction.

Cleaned the red of Ha in PS and adjusted the contrast.

Not clean as expected with that data: the shot you got are really good.

Wish you a nice day!

Pump up with O3. I saw its a rich O3 area and spectacular result can achieve. 

2 hours ago, Grzegorz Czernecki said:

Thanks, on Saturday I leave for 7 days under a very dark sky and pick up material

Lucky guy. I spent 4 days under a 21,5 sky. All raining....

Wish you clear sky and eager to see more shot.

12 minutes ago, Grzegorz Czernecki said:

Slightly different approach to processing

Wow. This second version is exploding. Like it! If 56 and 57 Cygnus was not so burn inside, should be a perfect shot!

10 hours ago, HunterHarling said:

Thanks. My bortal sky is much worse on the south-west side than the north-east, so I believe the sky around Cepheus is about Bortal 4. However, looking south-west is probably Bortal 6 or worse I think I'm pretty lucky to have the better northern sky though, as I can capture the targets as they rise   

Wow..... Both to much for me. I'm under a 8 or 9.... In this case I understand a so long exposure. Did you also try shorter sub and a lot more?

Excellent colours and processing. What was the Bortle sky? 300" on RGB is a huge amount (for me) with the asi1600.

@wimvb, thank you for the appreciation. I must first collect sone more oxigen as its really poor now. The mapping is a mix ( @ john) in SHO with a sinthetic green obtained in pixelmath. 

i agree to make it more dramatic because this is my intention but after trying, i loose definition. Anyway will.give a try.

Quick and dirty 20x240" in Ha and O3 combined in PI (HO)

Mount EQ5 with 80ed and asi1600mm.

I really appreciate constructive criticism as well as any suggestions, with many thanks.