IC1393 in HOO

[don4l]

Here is a HOO version of IC1396.  It is 110m of Ha, and 150m of OIII., total 4 hours 20 min

I have the impression that I could do with a lot more OIII data.  I found an add on for Gimp called GMIC, and used "Iain's Noise Reduction".  This seemed to work magic.

STL6303 on FSQ106ED af F3.6.

Acquired with CCDCiel, Indi.  Calibrated and stacked in CCDStack.  Finished in Gimp.

 

[Rodd]

Very good bicolor.\

Rodd

[don4l]

2 hours ago, Rodd said:

Very good bicolor.\

Rodd

Thank you, Rodd.

If you have any advice, then I am all ears.

The Ha in this seemed very strong, so I didn't see the point in gathering any more.  I cannot see that 110 minutes revealed more than the first 30 minutes.  The OIII was the opposite.  I suspect that I would need many, many more hours of data to make any difference.  However, this is new territory for me, so I am very happy to take advice.

One thing that disappoints me is that the "trunk" seems a bit blurry.  I guess that more OIII will help???

 

[Rodd]

21 minutes ago, don4l said:

Thank you, Rodd.

If you have any advice, then I am all ears.

The Ha in this seemed very strong, so I didn't see the point in gathering any more.  I cannot see that 110 minutes revealed more than the first 30 minutes.  The OIII was the opposite.  I suspect that I would need many, many more hours of data to make any difference.  However, this is new territory for me, so I am very happy to take advice.

One thing that disappoints me is that the "trunk" seems a bit blurry.  I guess that more OIII will help???

 

You have run into the bicolor dilemma--trying to capture the details contained in 3 channels with only 2!.  Much of the trunk is contained in the SII data.  Unlike the Veil Nebula, SII is strong in the Elaphant's Trunk.  One thing about more data, even if you don't really see the benefit right away, is that the more signal you have, the more it cane be sharpened, or otherwise processed.  the more data you have the less noise suppression you need. 

If it were me, I would collect SII.  Is there a reason you don't?  Also--remember this is a widefield image taken at a relatively small focal length and 9um pixels.  the resolution will be somewhare north of 4 arcec/pixl if I am not mistaken. 

Rodd

Edited September 9, 2019 by Rodd

[john2y]

It looks like a really nice image but I'd definitely crop out the stacked edges, also try to denoise it a little less, a little noise is better than completely smoothed out image 😉 

[don4l]

10 minutes ago, Rodd said:

You have run into the bicolor dilemma--trying to capture the details contained in 3 channels with only 2!.  Much of the trunk is contained in the SII data.  Unlike the Veil Nebula, SII is strong in the Elaphant's Trunk.  One thing about more data, even if you don't really see the benefit right away, is that the more signal you have, the more it cane be sharpened, or otherwise processed.  the more data you have the less noise suppression you need. 

If it were me, I would collect SII.  Is there a reason you don't?  Also--remember this is a widefield image taken at a relatively small focal length and 9um pixels.  the resolution will be somewhare north of 4 arcec/pixl if I am not mistaken. 

Rodd

The reason that I am not collecting SII is twofold.  The first reason is that my SII filter produces terrible halos.  I haven't upgraded yet because the internal filter wheel in my camera only has 5 slots.  They are, OIII, G,B,, Ha and empty.

The second reason is that I cannot change filters easily.  The threads on the adapter that connects to the reducer are very worn and I cannot be sure that I will get the camera back on if I take it off.   I have recently ordered a new camera which has 6u pixels and a 7 position wheel.  So, a new SII filter may be on the cards. 

I have been wondering if an hours worth of Green data would add anything?? 

 

 

[don4l]

39 minutes ago, john2y said:

It looks like a really nice image but I'd definitely crop out the stacked edges, also try to denoise it a little less, a little noise is better than completely smoothed out image 😉 

 

I must admit that I felt that the noise reduction was too strong.  I've already reduced the effect, but  I'll have a play to see if I can learn how to use it properly. 

 

 

[Rodd]

11 minutes ago, don4l said:

The reason that I am not collecting SII is twofold.  The first reason is that my SII filter produces terrible halos.  I haven't upgraded yet because the internal filter wheel in my camera only has 5 slots.  They are, OIII, G,B,, Ha and empty.

The second reason is that I cannot change filters easily.  The threads on the adapter that connects to the reducer are very worn and I cannot be sure that I will get the camera back on if I take it off.   I have recently ordered a new camera which has 6u pixels and a 7 position wheel.  So, a new SII filter may be on the cards. 

I have been wondering if an hours worth of Green data would add anything?? 

 

 

Sounds all too familiar--except even with brand new threads I often have a damnable time uncsrewing the spacers from the camera and each other--especially ones with low profiles.  Let me tell you when it 10 degrees F it is a monumental task.   That is the one major drawback of all threaded systems.  I use a canning jar cap remover that is equipped with rubber for gripping the top of canning jars.  It has 4-5 different diameter holes so one is bound to fit the part--works like a charm.  Still a lot of work though.   

I never understood why they make a 5 slot wheel--I guess for LRGB and Ha.  You have mixed the narrow band with the broadband.  I don't think the green filter will add much.  In a Hubble Palette image Ha is green and you already have sufficient Ha.  In your bi-color image--I would get a red filter for your empty space so you could have RGB stars.  But--then you are restricted to broadband and Ha.  You really need that 7 filter wheel.

Rodd