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Elephant Trunk Nebula - 9 Hs of Ha and OIII with a Nikon D5300a


Xiga

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Finally managed to add some proper Ha to the previous version (which was a noisy mess of a thing!), so this is now:

7 x 600s and 14 x 900s (4 hrs 40 mins) of Ha

17 x 900s (4 hrs 15 mins) of OIII

SII synthesized using a blend of 60% of Ha and 40% of OIII

 

Nikon D5300a

2" Baader filters

Skywatcher 80ED

Skywatcher HEQ5 Pro

50 Bias and 30 Flats

Guided with PHD2 and a finder-guider (QHY5)

Captured with SGP

Pre-processed in APP

Post-processed in PS

 

The extra Ha data has made a massive difference. So this one was much easier to process. Still not completely happy with the colours, I may tweak them a bit at a later date. But for now I think I'm pretty much done with this target, time to move on to a new one methinks!

C&C welcome as always. Clear skies!

https://flic.kr/p/GBb38M

 

 

IC 1396 HST image 2.jpg

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Nice image.  Personally I like the colours - they're false anyway, so you can choose what you prefer, but I like what you have done.  The elephant and surrounding nebula appear to be reaching up into the centre of the image - almost 3D.  I don't think you can do much better with this target.

I agree with what you say about extra time making the processing easier and the image smoother.  But what to do in this country?????

Chris

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That is a bit special.   Great effort.   It has 'real'  depth with the whole being greater than the sum of the parts. 

This Narrow Band Lark is pretty compelling.    You have to literally camp out and walk the hard yards to get the results.   You probably feel a bond to this Nebula from now on.

 

Sean.

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21 hours ago, cfpendock said:

Nice image.  Personally I like the colours - they're false anyway, so you can choose what you prefer, but I like what you have done.  The elephant and surrounding nebula appear to be reaching up into the centre of the image - almost 3D.  I don't think you can do much better with this target.

I agree with what you say about extra time making the processing easier and the image smoother.  But what to do in this country?????

Chris

 

21 hours ago, Craney said:

That is a bit special.   Great effort.   It has 'real'  depth with the whole being greater than the sum of the parts. 

This Narrow Band Lark is pretty compelling.    You have to literally camp out and walk the hard yards to get the results.   You probably feel a bond to this Nebula from now on.

 

Sean.

 

19 hours ago, MartinFransson said:

Pure awesomeness! Being a DSLR user myself I know how much work and skill that goes into your image.

Thanks for all the kind comments guys :icon_razz:

Sean, you're quite right. This being my first 'full' NB image (i.e Ha with OIII, can't see me ever bothering with SII) I do indeed feel a special bond with it, lol.

ps - What do people think about the framing? I keep going back and forth over the one above and the one below, but every time I think I prefer one over the other I change my mind!

 

IC 1396 HST image 2.jpg

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On 16/11/2017 at 14:12, Craney said:

I prefer the first one.   The  Dark region ( cloud within a cloud )  creates a central focus line.    The "Trunk" in the second one pulls the eye to the left.   Well that's my 2 penneth !!

 

 

Good point Craney! I knew there was a reason i specifically framed it that way :tongue:

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Decided i really wasn't happy with the colours in the last version. On second viewing i thought it actually looked a bit garish (why didn't anyone tell me, lol). 

So i went back and tweaked the colours. It's still garish mind, just in a slightly different way now :tongue:

 

 

IC 1396 HST image 3.jpg

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1 hour ago, PaulB said:

This is brilliant.

It shows the nebulae nicely.

DSLR cameras have certainly come a long way.

What is APP?

Cheers Paul.

APP is short for Astro pixel Processor. It already has some post-processing capabilities at the moment (with a lot more to come) but right now it's main USP's are in pre-processing (especially if you do Narrowband with a DSLR) and also mosaics, people are saying it handles mosaics better than anything else out there. I don't do mosaics myself, but I can certainly vouch for the DSLR Narrowband algorithms it uses.

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14 hours ago, StargeezerTim said:

Thats lovely... I am playing with the idea of getting another filter to add to my Ha and you have 'sold' the OIII to me!

Absolutely Tim. Go for it! :-)

Just a word of caution, you will need to shoot looong subs. I was shooting 15 min ones and they showed hardly anything at all in SGP (even with Auto Stretch set to High). I also now know to shoot 20 min subs for OIII going forward. The moon was also between 85-95% full on the 2 nights i shot the OIII, so i'm sure this had an effect too (in hindsight i really should have been shooting Ha instead!). When i stacked the OIII subs, i really had to stretch it to the absolute limit, and it was a noisy mess! (see below). I then blurred it to clean it up a bit, knowing it was only ever going to be used for the colour layer anyway, so it wouldn't matter too much. I've attached pictures below of the OIII stack (after a DDP stretch applied in APP, and it still showed very little!), followed by the aggressively stretched one i ended up using when combining the 3 images together to create the HST image. 

FWIW, i'm also considering upping the ISO just for the OIII subs in future, to try and lift the signal further out of the read noise floor (i.e push the histogram further to the right). It would mean i would lose some Dynamic Range, but the more i think about it the more i don't think it will be too big of an issue, seeing that in most objects the OIII signal tends to be secondary to Ha (and significantly so, most of the time) so it might not show itself up in the final image. Not completely sure about this though, and i'm loathe to test it out and ruin a clear night! (which as we all know are precious around these parts). 

 

OIII Stack.jpg

OIII Stack Processed.jpg

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11 hours ago, sloz1664 said:

Fabulous image and love the Hubble Pallet colour scheme. Regarding APP. How are you getting on with it and do you only calibrate it or are you pre-processing as well. Have you tried the mosaic feature yet?

Steve

Thanks Steve. 

I haven't done any mosaics (no plans to either any time soon), but from reading the forums and seeing what others are experiencing, it seems like APP might just be the current No. 1 choice for those who do a lot of mosaics. People were finding it was giving better results than P.I even. 

APP is pretty easy to get the hang of. I actually like the 'flow' of how the calibration and stacking works. Once you get your head around it, it actually makes sense (whereas every time i look at a P.I video i get heart palpitations at all the various checkboxes and options, none of which seem intuitive to me at all). My APP workflow basically goes something like: calibrate all the Ha lights then save them. Then do the same with the OIII lights. Then, clear everything and load back in ALL the calibrated files (both Ha and OIII) and register them all together. Then at the end, i de-select the OIII subs and just stack the Ha ones, then vice-versa, i de-select the Ha subs and just stack the OIII ones. This gives me my 2 stacks which are already perfectly aligned and ready to be layered together in PS. Easy-peasy! :-)

 

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In the true spirit of not knowing when to stop (note to self, Stop! lol), i had a go at using 'HDR Toning' for the first time in PS (after watching a Ken Crawford video). It's a very powerful tool, but boy is it easy to overdo an image with it, especially when you've been looking at it for too long!

What do you guys think, would you say this is an improvement over the previous version, or have i gone too far?

 

 

IC 1396 HST image 4 (HDR).jpg

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3 hours ago, Xiga said:

Thanks Steve. 

I haven't done any mosaics (no plans to either any time soon), but from reading the forums and seeing what others are experiencing, it seems like APP might just be the current No. 1 choice for those who do a lot of mosaics. People were finding it was giving better results than P.I even. 

APP is pretty easy to get the hang of. I actually like the 'flow' of how the calibration and stacking works. Once you get your head around it, it actually makes sense (whereas every time i look at a P.I video i get heart palpitations at all the various checkboxes and options, none of which seem intuitive to me at all). My APP workflow basically goes something like: calibrate all the Ha lights then save them. Then do the same with the OIII lights. Then, clear everything and load back in ALL the calibrated files (both Ha and OIII) and register them all together. Then at the end, i de-select the OIII subs and just stack the Ha ones, then vice-versa, i de-select the Ha subs and just stack the OIII ones. This gives me my 2 stacks which are already perfectly aligned and ready to be layered together in PS. Easy-peasy! :-)

 

Even if you don't register each set in PI or any other software, you can align them afterwards with DynamicAlignment just by picking a few stars.

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Hi Ciarán

Yes I like the HDR version it has certainly brought more depth to it. Regards APP. I have been using it for around 2 months now and use it for calibration only, which it excels at. My post processing is done in PIxinsight. I was just curious if you performed any post processing thats all.

Steve

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Thanks guys!

When I did the HDR version I also managed to correct the horrible blue halos that were present in most of the stars. Some were absolutely huge and protruded way beyond the stars edge in many cases (they were most noticeable in the golden areas).

There’s probably an easier way to do this, but the method I came up with was to first create a starless version (I used one of Annie’s Astro Actions for this). I then used the Spot Healing Brush to clean up any remaining star outlines. Once I was happy with it, I then simply layered it back on top of the original HDR version and set it’s blend mode to Color. The Luminosity of each star remained unchanged but the surrounding blue halos were then replaced with background rather than all that ugly blue halo. Hopefully someone else may find this method useful too.

I’ve attached the starless version below for reference.

 

IC 1396 Starless.jpg

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  • 1 month later...

Due to the continual bad weather here in the UK, i decided to go back and have another go at processing my Elephant Trunk data, as in hindsight i really wasn't happy with how it looked. 

From looking at various images of this object online, it really does throw up so many different variations in colour. I see some with Cyan, Turquoise, Purple, and even Green in them, and to be honest they all still look good! Personally though, i tend to find the ones i like best are the ones that don't go overboard on the colours, and in fact, keep the image looking much darker than i would have otherwise expected. I know with a False Colour image there is no real right or wrong way to present an image, it's all personal preference really, and after looking at my image for so long i think i'm going blind to it, lol, so what i'm really looking for is something along the lines that most people deem to be aesthetically pleasing for this target. 

The 2 biggest changes i made were, to add a lot of black to the Blues and Cyans using Selective Colour Adjustments, to darken the colours without darkening the background. I also applied a Surface Blur at the end. I really like this i have to say, i think it does a good job of evening out the general graininess of the background, without losing any detail (as would happen with regular noise reduction).

So what do you guys think. Is this an improvement on the previous version or not? And more importantly, is there anything obvious that could be done differently or better? Note, don't be afraid to be harsh, i'm looking for ways to improve so don't mind criticism.

Cheers guys, and clear skies as always!

IC 1396 HST image 6.jpg

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