Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

stargazine_ep24_banner.thumb.jpg.56e65b9c9549c15ed3f06e146fc5f5f1.jpg

gorann

Tulip Nebula Sh2-101 - first HaRGB with the RASA 8

Recommended Posts

Posted (edited)

My first HaRGB with the RASA 8. RGB with ASI2600MC (87 x 2 min, gain 100, moonless on 25 August) and Ha with ASI1600MM (61 x 5 min, gain 139, full moon on 31 August). Baader fast Ha 2" filter.

This is a Ha emission region in Cygnus and the Tulip is to the right, and adds to my Sharpless collection. Not sure if the other nebulosity in the image has any designation, but it is quite a lot of it around. There is also some nice dark nebulosity and three intriguing red filamental structures just to the left of the centre of the image. I wonder what they may be.

The RGB image looked rater uniteresting so the Ha collected last night made a big difference.

2020823-24 Tulip Neb RASA HaRGB PS24smallSign.jpg

Edited by gorann
  • Like 19

Share this post


Link to post
Share on other sites

Nice image Göran and good to see the 1600 getting an airing 👍🏼

Share this post


Link to post
Share on other sites
11 hours ago, ampleamp said:

Nice image Göran and good to see the 1600 getting an airing 👍🏼

Thanks a lot Alistair. Yes it is now working hard and doing a good job:hello2:. Finally astrodarkness up here and I had a few clear nights recently.

Share this post


Link to post
Share on other sites

What a cracker...you certainly have the rasa tuned in ...nicley captured and processed...

Must be a game changer being able to get all them photons quicker. 

Well done 

Paul

Share this post


Link to post
Share on other sites
3 hours ago, ultranova said:

What a cracker...you certainly have the rasa tuned in ...nicley captured and processed...

Must be a game changer being able to get all them photons quicker. 

Well done 

Paul

Thanks for you kind words Paul! Yes, at least now when nights still are short it has clearly been a game changer. Now I can get the data for an image in one night, or two nights if I add Ha. I am surprised how well it keeps focus (no refocusing during a night so far) and collimation has been spot on from the factory. Only issue is minor tilt in the cameras - the RASA is apparently very sensitive to this due to the low f-ratio. I can live with it and mostly fix the corner stars it in processing, and it is probably only an issue for me and other pixel peepers.

Share this post


Link to post
Share on other sites

Beautiful work, seems you are liking the new camera, your sure using it well Goran.

Alan

Share this post


Link to post
Share on other sites
4 hours ago, alan potts said:

Beautiful work, seems you are liking the new camera, your sure using it well Goran.

Alan

Thanks Alan! Still at it - may be clear tonight so I aim to such up whatever Ha may reach northern Europe!

Share this post


Link to post
Share on other sites

Another fantastic image Gorann. Wish we had as many clear skies here! Could I ask do you remove the RASA8 optical window for the 1600MM and put it back in for the 2600MC? 

Share this post


Link to post
Share on other sites
9 minutes ago, AbsolutelyN said:

Another fantastic image Gorann. Wish we had as many clear skies here! Could I ask do you remove the RASA8 optical window for the 1600MM and put it back in for the 2600MC? 

Thanks!

I did remove the optical window since I am using a Ha filter for the ASI1600 (as suggested by both Celestron and Baader). Why should I put it back for the ASI2600 next time I go RGB - does it have any function that you know of?

Share this post


Link to post
Share on other sites
1 minute ago, gorann said:

Thanks!

I did remove the optical window since I am using a Ha filter for the ASI1600 (as suggested by both Celestron and Baader). Why should I put it back for the ASI2600 next time I go RGB - does it have any function that you know of?

I don’t know ... I was wondering if it affects the focus position and is needed to be in place if not using a filter (ie osc). Just curious as planning to try osc on my rasa 

Share this post


Link to post
Share on other sites
3 hours ago, AbsolutelyN said:

I don’t know ... I was wondering if it affects the focus position and is needed to be in place if not using a filter (ie osc). Just curious as planning to try osc on my rasa 

From what I have read the chip distance should be 29 mm with the window in, and still 29 mm with a filter but then the window should be removed. I assume there are two reasons for this. First, the effect of the filter on the light path (prolonging it with 1/3 of the filter glass thickness) is removed by taking out the window. Secondly, having both a widow and a filter may cause some refelction/halo problems, but the latter is just a guess. I actually have now idea why they put the optical window in there except that it gives Celestron a reason to sell their light pollution filter that can be bought to replace the window.

  • Thanks 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.