The Cat's Eye Nebula HaOiiiRGB from last night

[gorann]

Surprisingly it stayed clear all night so I got almost 14 hours from my dual Esprit rig on this enigmatic planetary nebula. There was a full mon of course but I still took the chance of collecting some RGB with the Esprit 100 and ASI071. I only expected that I at best could use it for star colour but the data turned out to be virtually without gradients. It probably helped that the scope was pointing away from the moon. I also decided to go for rather short subs so I ended up waiting for my computer to stack 263 x 90s of RGB data. On the Esprit 150 the ASI 1600MM was collecting 2 hours of Ha (Baader 3.5 nm) and 5 hours of Oiii, (Baader 8.5 nm)  yielding another 200 or so subs. I also shot some 10s and 30s subs to save the very bright core of this nebula - the actual eye.

The result of shooting the sky with the Esprit 100 was a quite wide field with a rather small nebula, so I post it from wide to narrow here.

Suggestions and comments most welcome!

Cheers

Göran

Edited October 15, 2019 by gorann

[carastro]

Great job Goran.  I found this Nebula extremely difficult to process due to the bright core.  You seem to have done very well and got some shape out of it. 

Carole

 

[alan potts]

I was jumping around the sky last night looking a planetary nebs and thinking, too small, too small and then turned to globular clusters. This of yours has come out very nicely indeed and maybe like yourself I have been thinking, with the Moon up all is not lost. Thanks for posting these beautiful captures, just goes to show what can be done.

Alan

[gorann]

11 hours ago, carastro said:

Great job Goran.  I found this Nebula extremely difficult to process due to the bright core.  You seem to have done very well and got some shape out of it. 

Carole

 

Thanks Carole! I noticed the burnt out core in the first 3 minute subs so I took some 10s and 30 s exposures, maybe 8 minutes in total, and that saved it.

[gorann]

51 minutes ago, alan potts said:

I was jumping around the sky last night looking a planetary nebs and thinking, too small, too small and then turned to globular clusters. This of yours has come out very nicely indeed and maybe like yourself I have been thinking, with the Moon up all is not lost. Thanks for posting these beautiful captures, just goes to show what can be done.

Alan

Thanks Alan! The 1050 mm FL of the Esprit 150 is relatively OK for this one, although I am tempted to use my Meade 14" next time - but then I need a really steady sky.

[carastro]

Quote

 I noticed the burnt out core in the first 3 minute subs so I took some 10s and 30 s exposures, maybe 8 minutes in total, and that saved it.

I did the same, but I think I did only 30sec subs, so looks like your 10sec subs were much better.

Carole 

[ollypenrice]

The charm of PNs in widefield is imagining a time lapse in which all the medium mass stars produce their own. What a sight that would be but I'll happily settle for this one.

What's your pixel scale, Gorann? I did this at about a metre and 0.9"PP. Like you, I used shorts for the core.

Olly

[gorann]

7 hours ago, ollypenrice said:

The charm of PNs in widefield is imagining a time lapse in which all the medium mass stars produce their own. What a sight that would be but I'll happily settle for this one.

What's your pixel scale, Gorann? I did this at about a metre and 0.9"PP. Like you, I used shorts for the core.

Olly

I used two scopes. For the HaOiii data (which shows the nebula - hardly a trace of it in RGB) I used the Esprit 150 with ASI1600MM so 0.75 "/pix. For the RGB I used the Esprit 100 with ASI071 (OSC) so 1.79 "/pix. Before merging them I scaled the RGB image to 0.75"/pix (which made a huge file). I then cropped down  in two stages as seen. I also downsampled the jpg images here to about 70% of the original.

I had another look at my 10-30s core data and found more color and structure in there so here is an updated version with more of a cat's eye in the center.

 

 

 

Edited October 14, 2019 by gorann

[Laurin Dave]

Very nice Goran, well done.

Dave

[gorann]

4 hours ago, Laurin Dave said:

Very nice Goran, well done.

Dave

Thanks Dave! Got to spend a few more nights on it to even get close to your level on the Veils - not sure I have the stamina😉

[gorann]

10 hours ago, carastro said:

I did the same, but I think I did only 30sec subs, so looks like your 10sec subs were much better.

Carole 

I have done the same misstake a few times. So I now try to make it a rule to spend just a few minutes on short exposures if I aim at bright objects like this one. It takes no time at all and is a great help against the frustration of looking at blown out cores.