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Bubble Nebula in Cassiopeia

Started by Fay, Oct 17, 2010, 13:18:52

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Fay


Went out to polar align EQ6 & ended up staying out for a while.

This is 10x600, SW120, Atik 314L, ha, o.8fr. 171010

As the nebula reached the zenith, the guiding seemed to suffer. I have only stacked 10 subs here, but have got another 3. The guide graph looked good all the time, so was surprised to see stars sllghtly elongated.

It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

MarkS


Fay,

That really is a very good image.  It's very clean, very detailed and processed very nicely to bring out the contrast.  The brighter part inside the bubble has burnt out but not severely.

If this had been taken at DSC I could understand it, but I guess this was taken from home?  Which Ha filter are you using - in particular how narrow is it (12nm or 6nm)?  How were the conditions - I decided not to image because of tooo much moon - maybe a wrong decision!

The guiding problem you described is flexure - something has moved slightly as gravity has started to act from a different direction.  Maybe the guidescope has flexed relative to the main scope or maybe one of the cameras has flexed relative to its scope.

Well done.

Mark

Fay

Thanks a lot Mark. Well the filters are the Atronomik one's, I was looking at the halo around the large star & when looking at other images, I was thinking it is a common problem as there are a lot of spikes around for that star!


It was weird as the guiding looked very good, it seemed that the slightest  movement would produce a bad sub. Perhaps the balance was not right, & as it all changed positions it showed up.

If I put the bad 3x subs into the image, there was not a lot of difference in quality, & it is another 30 mins!
Yes did it last night.

It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

MarkS


Is it an Astronomik 12nm filter or a 6nm filter (the 6nm filter is the expensive one)?

Adding 3 subs to 10 subs is only a 30% increase - it will make hardly any difference to be honest.  To see a difference you need to double the number of subs and even then the difference is marginal. 

Do an experiment where you compare the quality of 1 sub, 2 subs, 4 subs, 8 subs, 16 subs - it's very instructive.  it gives you an idea of what improvement expect when doubling your total exposure time.

Mark

Fay

Thanks Mark. I am thinking they are the 12m filters
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

Mac


mickw

That's really nice Fay, loads of detail
Growing Old is mandatory - Growing Up is optional

Fay

It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

RobertM

Hi Fay,

Sorry I missed this earlier, that's a really great result; nicely focused, well processed with good detail.  I'm sure you could extract a knats of detail from the shark in the bubble and I still think your black points are set a tad too high missing some nebulosity (I could be wrong in this case!).  They are personal finer points that don't detract from an excellent result.

Robert


Carole


Daniel

That's a fantastic result Fay, you've really balanced out the bright core and the surrounding nebulosity well, Love how sharp the detail is while keeping the image noise free!

Daniel
:O)

The Thing

Stonking image Fay. Congratulations!

Fay

Thankyou everyone, very kind of you
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

Mike

Really nice image Fay. Some of the best detail i've seen in the Bubble.
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Fay

That is nice of you Mike, thanks
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

Ian