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peter shah

The Horse Head in HaRGB

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11 hours ago, sloz1664 said:

I'm presently imaging Barnard 33 only and fortunately Alnitak is not in the image :)

Steve 

That won't necessarily stop it from playing hell with your data, though. Off-shot flares are often, even usually, worse than those on-shot. I've never found a way of predicting how they will play out. Just luck, I think.

Olly

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Outstanding image Peter and I know it's not the main attraction in this area but NGC 2023 is the star of the show for me, beautiful. I don't think I've ever seen a version quite like it.

Edited by johnfosteruk
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14 minutes ago, johnfosteruk said:

Outstanding image Peter and I know it's not the main attraction in this area but NGC 2023 is the star of the show for me, beautiful. I don't think I've ever seen a version quite like it.

I know what you mean...I know they are different objects but I wonder if the Horse Head would have the same appeal if it wasn't there

 

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That's come out very nicely indeed! You've managed great colour considering that you've merged the Ha in and have a relativity smalls set of colour data. 12 hours?? I just don't have the patience for that kind of effort! It was certainly worth it, though.

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1 hour ago, ollypenrice said:

That won't necessarily stop it from playing hell with your data, though. Off-shot flares are often, even usually, worse than those on-shot. I've never found a way of predicting how they will play out. Just luck, I think.

Olly

I see your point Olly. Although Alnitak is not present in my image NGC 2023 is. It certainly shows in the RGB image but not prevalent in the Ha image.

Steve 

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By far one of the best horse heads i've ever seen. Awesome stuff Peter.

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36 minutes ago, souls33k3r said:

By far one of the best horse heads i've ever seen. Awesome stuff Peter.

You are very kind, thank you Ahmed... there are plenty of great HH about. It might have been a little crisper if it got higher in the sky....I guess another one of the downsides imaging in the UK.

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4 hours ago, peter shah said:

I have weighted my exposure to give a more or less correct colour balance. This saves on wasted exposure times where you would only process the heaviest signal only part way to get the correct colour. This method I can give equal curve stretches to each frame. It also makes colour balancing easier.

you are very kind Rodd.... Alnitak was extremely difficult to control

thank you :thumbsup:

That’s another advantage of astrodons, they are reported to be 1:1:1 which makes things very easy.

Rodd

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2 hours ago, Shibby said:

That's come out very nicely indeed! You've managed great colour considering that you've merged the Ha in and have a relativity smalls set of colour data. 12 hours?? I just don't have the patience for that kind of effort! It was certainly worth it, though.

Hi Lewis, I used the Ha in several ways layering with the screen mode in PS and blending the Ha+RGB in with the RGB.... very time consuming. It still showed a lack of contrast around Alnitak and that is where most of the work went.

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4 minutes ago, Rodd said:

That’s another advantage of astrodons, they are reported to be 1:1:1 which makes things very easy.

Rodd

That would be great.... I'd like to find out more on that I always thought you needed to do a G2V calibration even with Astrodons.

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It would be interesting to combine the data sets from your image and this one I did a while ago.  Very surprised to see a very similar FOV with such different apertures (12.5 and 5).  Unfortunately, I only have the JPEG due to data loss.  It might still be possible though.  

https://www.astrobin.com/330382/P/?nc=

Rodd

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1 hour ago, Rodd said:

It would be interesting to combine the data sets from your image and this one I did a while ago.  Very surprised to see a very similar FOV with such different apertures (12.5 and 5).  Unfortunately, I only have the JPEG due to data loss.  It might still be possible though.  

https://www.astrobin.com/330382/P/?nc=

Rodd

I don't think there is much going to be gained using a Jpeg file but you are more than welcome to have a look at my fits data and see what you can do with it. :thumbsup:

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Splendid Peter - of course it REALLY NEEDS a panel below, above and to each side ??.

Fabulous colour balance across the whole field and details within NGC 2023 showing very nicely along with the rolling Ha gas in the dark dust below the HH.  Congratulations!

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Fabulous Peter.  The highlight for me is the reflection nebulosity below the HH, it's beautifully rendered.

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9 hours ago, peter shah said:

That would be great.... I'd like to find out more on that I always thought you needed to do a G2V calibration even with Astrodons.

With the Chroma's Peter my G2V's worked out at with the 10" RC Truss: -

Red 1.16
Green 1.00
Blue1.33

So although the filters maybe 1:1:1 the OTA is surely going to affect the amount of light reflected

With the Esprit 80 the G2V's worked out at: -

R 0.98809
G 1.00
B 0.8125

So using your advice Peter, I do G2V's on every OTA combination even though I am using the same filters, its obvious really that one piece of glass is going to reflect different amounts of light irrespective of the filters used.

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24 minutes ago, Jkulin said:

With the Chroma's Peter my G2V's worked out at with the 10" RC Truss: -

Red 1.16
Green 1.00
Blue1.33

So although the filters maybe 1:1:1 the OTA is surely going to affect the amount of light reflected

With the Esprit 80 the G2V's worked out at: -

R 0.98809
G 1.00
B 0.8125

So using your advice Peter, I do G2V's on every OTA combination even though I am using the same filters, its obvious really that one piece of glass is going to reflect different amounts of light irrespective of the filters used.

The numbers with the refractor are pretty close.  Does APO quality affect the ratios I wonder?  Can you really see the difference?  The more subs you collect the less noise you have--after a certain point the signal doesn't really change much.  When I collect 200 red and compare it to 400 red--not much of a difference.  I am unsure if I believe that the difference between say an image with 100, 90, 85 will look any different than an image with 100, 100, 100.

Rodd

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Hi Rodd, Peter has been helping me since I acquired my Chroma filters as he is a big advocate of G2V, due to technical issues and only 3 clear night since the end of October I can't advise whether they improve anything on my images, but I only have to look at Peters images to know not to argue ? 

Peter put me onto this Youtube Video, and after that he pointed me to a G2V star to evaluate, since then I have googled other G2V stars in my FOV and used them, here's a link to a G2V database https://web.njit.edu/~gary/322/G2V_stars.html: -

 

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IMHO one of the very best renditions of this much imaged region, and taken from a UK location too, great job!?

Myself and Tomatobro attempted a collaborative effort on this region in Ha and OIII, keeping Alnitak out of the FOV, but the subs were plagued with flares, spikes and halos from the blue supergiant. One spike was so strong after stacking it looked like a bright satellite trail right across the image below B33.....

6ABBB5D7-D158-4CDC-A76B-5111E7F0038D.jpeg

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On 05/02/2019 at 19:58, peter shah said:

Imaged with my AG12 and H35. A massive task to tame Alnitak, it took over 12hours to process this one. Exposure times were 4x900s in H-alpha, 4x900s in Red, 4x820s in Blue and 4x640s in Green. Processed in Photoshop and Lightroom.

Comments welcome 

thanks for looking :thumbsup:

 

 

The Horse Head final Stars.jpg

Wow, just Wow Peter! 

I'm not sure i'll ever look at another picture of the HH & Flame quite the same after seeing this. And to think this was done with just 1 hr of Ha and ~1hr each of R, G, and B ? 

Looks like you've definitely found the cure for UK weather. Blitz it with big, fast optics. Sure who needs long integration times anyways?! ? 

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14 hours ago, Barry-Wilson said:

Splendid Peter - of course it REALLY NEEDS a panel below, above and to each side ??.

Fabulous colour balance across the whole field and details within NGC 2023 showing very nicely along with the rolling Ha gas in the dark dust below the HH.  Congratulations!

Thank you Barry....mosaic...Hmm?...no! ?

11 hours ago, Rodd said:

  I am unsure if I believe that the difference between say an image with 100, 90, 85 will look any different than an image with 100, 100, 100.

That is a very good point Rodd....and balancing colour with lots of data is easier because you don,t lack signal in certain areas. However the real point and the main reason for me using G2V  calibration is the amount of time saved acquiring the data as we know that sky time is precious in the UK.

10 hours ago, tomato said:

IMHO one of the very best renditions of this much imaged region, and taken from a UK location too, great job!?

Myself and Tomatobro attempted a collaborative effort on this region in Ha and OIII, keeping Alnitak out of the FOV, but the subs were plagued with flares, spikes and halos from the blue supergiant. One spike was so strong after stacking it looked like a bright satellite trail right across the image below B33.....

6ABBB5D7-D158-4CDC-A76B-5111E7F0038D.jpeg

Thank you.....and thats a great rendition beautiful tight stars.

Unfortunately trails, spikes and bad columns are an occupational hazard and does push processing to the limit...... still  always worth giving it a go.

9 hours ago, Xiga said:

Wow, just Wow Peter! 

I'm not sure i'll ever look at another picture of the HH & Flame quite the same after seeing this. And to think this was done with just 1 hr of Ha and ~1hr each of R, G, and B ? 

Looks like you've definitely found the cure for UK weather. Blitz it with big, fast optics. Sure who needs long integration times anyways?! ? 

Thank you you are very kind.... a fast scope and and a little bit of luck

 

13 hours ago, MartinB said:

Fabulous Peter.  The highlight for me is the reflection nebulosity below the HH, it's beautifully rendered.

Yes very often overlooked....I dont think I've ever seen it done as a stand alone image.... I guess a big scope and steady skies are rare.

 

8 hours ago, bob-c said:

A fantastic image Peter.

Bob.

?

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5 hours ago, peter shah said:

That is a very good point Rodd....and balancing colour with lots of data is easier because you don,t lack signal in certain areas. However the real point and the main reason for me using G2V  calibration is the amount of time saved acquiring the data as we know that sky time is precious in the UK.

Would that it were possible for a G2V calibration to solve my "I need more data" problems.  That certainly would be great.  But do the benefits of G2V calibration extend to noise suppression?

Rodd

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