Wizard Nebula NGC 7380 Ha

[Carole]

My first attempt at this object.

I went to visit my aunt in Herstmonceux over the weekend and it was forecast to be clear so I took my kit with me.  Friday was clear but hazy so I didn't bother.  Saturday was nice and clear but as there was a waning gibbous Moon decided to do narrowband.  

Unfortunately I wasted a few subs due to guiding problems which I managed to sort and all due to being out of my comfort zone and forgetting to do things!!!  Then the object disappeared behind the house before I could get as much as I wanted.

So only 11 x 900secs Ha
ED80, Atik383L
Captured in Artemis and processed in PS.

Planning to add Oiii and Sii to this, weather permitting.
CROP

Would probably have been better with the ED120, but wasn't sure what would be available to image from my Aunt's back garden.

[JohnP]

Shame you didn't get too much time on this - FOV is great. Look forward to the colour.

[Carole]

Thanks John,

Hoping to get more Ha data when I do the Oiii and Sii.

Carole

[MarkS]

That's certainly a good start Carole.  I wonder how much difference the moon made?

[RobertM]

Hi Carole,

That's a tough subject especially with the moon around.  Unfortunately it's very pixellated probably due to beinga small jpeg.  Have you a link to a larger version ?

Robert

[Carole]

Is this PNG any better?



This is the zoomed in version on the gallery:
http://gallery.orpington-astronomy.org.uk/albums/userpics/10047/Wizard_Ha_11_x_900secs_Ha_CROP.png

That's a tough subject especially with the moon around. 

I thought narrowband were supposed to be OK with a bright Moon.

Carole

[RobertM]

Yes narrow band are but it depends how narrow.  At 12nm they are seriously affected and at 7nm much less so.  It really depends on your location and how bright the sky is.  OIII would be affected much more in moonlight Ha less so.  I'll take a look at the image when I get in.

Robert

[Carole]

Hi Robert. 
This is Ha Baader 7nm - dark location at Herstmonceux.

Carole

[RobertM]

That does look nice Carole.

I'm not sure whether this is as a result of your processing but the bright stars seem to be very sharp and all the others slightly blurred (maybe slightly out of focus ?).  I've been comparing it to my attempt where the stars are more even http://forum.orpington-astronomy.org.uk/index.php?topic=3981.0.  It could be that yours is more correct or less incorrect depending on viewpoint.

Robert

[Carole]

Thanks Robert and thanks Mark.

the bright stars seem to be very sharp and all the others slightly blurred

Yes I know what you mean, I just assumed it was an inherent thing with this camera, as I think previous images have looked like this too.

Carole

[MarkS]

the bright stars seem to be very sharp and all the others slightly blurred

Yes I know what you mean, I just assumed it was an inherent thing with this camera, as I think previous images have looked like this too.

It's not the camera. Those "sharp" stars also have a dark ring artifact.  Have you applied some kind of sharpening?  Alternatively could it be spline interpolation (or similar) during the registration of subs - I encountered this once before.

Mark

[Carole]

It's not the camera.

Hi Mark, I was referring to the fainter stars looking slightly blurred.

I might have applied a bit of sharpening to this image, it's not something I normally do, so might not do it again.  I will probably re-process the Ha once I get Oiii and Sii data.

Thanks
Carole

[Rocket Pooch]

Hi,

I don't think your focus is bang on and your black and white points look at little off, specifically the white.  Can you put a zipped FIT or Tiff up somewhere (stacked) with nothing done to it, I'd like to have a play.

Due to being in employment and mainly out of the country I haven't got time for any imaging


Chris

[Carole]

Hi Chris,

Yes I think focus is just a little bit out, I think I am going to have to learn the FWHM method as up until now I've always used a Bahtinov, but I don't find that quite so easy with a CCD camera.  I got some Oiii and Sii data last night and am just about to reprocess the Ha.  I am also planning to do some more Ha data as this isn't really enough.

I am struggling a bit with combining colours/filters and I wonder if I can put the whole shabang into a folder once I've stacked it and perhaps you would like to have a "go" at that too while you are at it.  There doesn't seem to be much data in Oiii and Sii but as others have processed NB images of this there must be some in there somewhere.  Also I haven't got much Oiii data yet as I had some problems and wasted a few, so again this needs more on another night.  However I am doing this for practice as I am very much a beginner with filters and narrowband.
So far have 1h 45mins on Ha (900secs subs), 2 hours Sii (900 sec subs), 1 hour Oiii (1200 sec subs)

I have so far been using channels to combine coloured filters and only seem to end up with one colour, I am converting the combined image to RGB mode, should I also be converting the mono images into RGB before pasting them into the layers?  Though both the tutorials I have read only mention the combined file needs to be changed to RGB.

Also been looking at tone mapping.

Just stacking the Sii and Oiii and will put some stacked and unprocessed files into Dropbox.

Thanks
Carole

[RobertM]

In photoshop you need to convert one of either ha/sii/oiling to rgb then paste the sii and oiii each into one colour channel ie. paste the sii into red and oiii into green.  I cant remember whether you'll need to convert the sii/oiii to colour too so do some experimenting.  There are obviously a few combinations of this so try not to get unpleasant revolting combinations - there are enough out there on the web !

Robert

[Carole]

Thanks Robert,  I have tried both ways now and it doesn't seem to make any difference so long as the combi layer is in RGB. 

Well I've tried Hubble and the result is revolting, I cannot seem to get the 3 colours to blend well together with the stars looking decent, so i tried bicolour, which is a bit better.

The best result has come out in false colour, but I think I need to get a lot more data to make this look anything like respectable.  I'll post the result in the next post.

Meanwhile Chris requested I post up my stacked data.  As I say I don't think there is enough of it, and possibly I need a lot more shorter subs to overlap the noise - advice gratefully received on this.

These are the links:

Ha 1.75 hours in 15 minutes subs (
https://dl.dropbox.com/u/5730788/Wizard%20Nebula%20Dec%202012%20NB/Wizard%20Ha%201.12.12%20900secs%20x%2011%20desktop.TIF

Oiii Only one hour so far in 20minute subs (3)
https://dl.dropbox.com/u/5730788/Wizard%20Nebula%20Dec%202012%20NB/Wizard%20Oiii%203%20x%201200secs%205.12.12.TIF

Sii 2 hours in 15min subs (
https://dl.dropbox.com/u/5730788/Wizard%20Nebula%20Dec%202012%20NB/Wizard%20Sii%20900secs%20x%208%20on%205-12-12.TIF

[Carole]

This is the HaRGB false colour result.  I cannot seem to get the stars to uniformly line up in the different filters.  They line up one side of the image and not the other, same kit
i.e. bottom left on this image red sits on top green below.  
Middle seems OKish
Top right of image green sits on top and red below.
Any idea why this is happening. Maybe there is some slight rotation, but I can't do any more than align two opposite stars in Maxim.

Image removed until I've done a bit more learning 

[RobertM]

Yuk, it's horribly blurred - what have you done to it