Jump to content

Banner.jpg.b89429c566825f6ab32bcafbada449c9.jpg

NGC2264 - The cone in bi colour

swag72

By swag72
in Imaging - Deep Sky

Recommended Posts

swag72

swag72

Posted
Posted

This is an addition to the mono cone that I produced. This is a bi colour image, using Ha and OIII - I find that I enjoy the colour possibilities with this and also the time saving when compared to a hubble palette as no SII is needed!!!

I look forward to your thoughts on this - I know these colours are not everyone's cup of tea and neither is the close-up work :)

Details

M: Avalon Linear Fast reverse

T: AT8RC CF

C: QSI690-wsg with 3nm and OIII filters

25x1800s Ha and 18x1800s OIII

Totalling 21.5 hours in total.

post-5681-0-09476800-1428045830_thumb.jp

You can see a larger res version here http://swagastro.weebly.com/recent-images.html

Link to comment
Share on other sites
  • Replies 26
  • Created
  • Last Reply
PhotoGav

PhotoGav

Posted
Posted

This is a beautiful image and a fantastic colour treatment of the mono version posted earlier. I'm afraid though, with this you have thorough disproved your own article about mono being 'better'!! This has a wonderfully religious light to it!

There is a lot of 'texture' to the darker areas - is that noise? I don't know the exact sub details, but knowing you Sara, there's plenty of time invested in this image. So, how come the noise? Is that just the opportunity cost of imaging at long focal lengths? Is it a stretching thing? Or is it just 'real detail'? It doesn't detract from the image at all, I'm just curious to understand its origin.

Link to comment
Share on other sites
swag72

swag72

Posted
  • Author
Posted

Thanks all for looking and commenting - Much appreciated.

@Gav - There really wasn't enough time invested in this image if I'm honest - I've recently completed an Ha of another part of this area and I could see a big difference in the noise levels between 37 and 46 subs - I reached the stage of impatience with this.

Lessons learnt!!

Link to comment
Share on other sites
Barry-Wilson

Barry-Wilson

Posted
Posted

Great resolution, the two stars (binary?) at the tip of the Cone are clearly separated.  I like the strong colouring, it aids in distinguishing elements of the structuring.

It's interesting to read your comment about noise.  Along with collecting sufficient data to minimise noise (a principle for us all to aim for . . . weather & life permitting!), the treatment of noise with reduction techniques does seem to vary widely between imagers (assuming correct application of the techniques), ie some prefer strong noise reduction to produce a smooth homogenous background, others leave remnants of noise perhaps to give a more nagtural, less synthetic feel to their image.  Is noise reduction or the degree of noise reduction a subjective and aesthetic preference do you think?  I wonder if there's a consensus?  I don't mean to hijack your thread, rather to understand your thinking as you contemplate how best to process your image and represent the target.

Barry

Link to comment
Share on other sites
swag72

swag72

Posted
  • Author
Posted

Thanks all for your continued comments and looking :)

@Barry - I would dearly love images with zero noise and in all honesty, with the refractor at f3.9 that's doable.... but at f8 and 1.6m I have learnt that this is a different beast totally. So after much soul searching and experimentation with stacking and calibration files, I have decided that some noise is better than the over smooth and mottled background that I do see around. As you say, I think it's a personal thing of taste as well as the lesser of two evils in my book.......... as well as at some point you need to draw a line in the sand and say 'that's enough, no more'

Link to comment
Share on other sites
ollypenrice

ollypenrice

Posted
Posted

Re noise, if you can see that NR has been applied then it's been over-applied. That's my take on it, anyway. I think Sara made a good call here and she's right that you really can't get it down at slower F ratios to the levels possible at F3.9.

Olly

Link to comment
Share on other sites
Martin-Devon

Martin-Devon

Posted
Posted

Yep, cracking good image, resolution and colours are spot-on. I've not seen the Cone itself before in such detail, so this is a first for me. In terms of noise and whether to reduce or not, I think it's a personal preference and one that changes with experience as well; the temptation is to hit it hard, but the detail in the image suffers and as Olly mentions it's easy to overdo it and as such it becomes obvious in the outcome - I've been guilty of this in the past. For me, it's the OIII data that's the biggest pain, always grainy to some degree (more than I would like) even with an Astrodon 3nM filter. 

Martin

Link to comment
Share on other sites
swag72

swag72

Posted
  • Author
Posted

Thanks all for looking and commenting - Interesting discussion regrading noise reduction. It is interesting as well what some see and others don't. For example on the mono image of this that I posted someone said that there was too much noise reduction and someone swore blind that none had been done!

I have found it so very target dependant it's been quite shocking. In a recent image, 13 hours of data and absolutely no noise reduction needed, yet on a faint target 23 hours and it's still noisier than I would like. The moon also affects subs considerably - So much so that even with Ha I rarely go out when the moon is near full...... it creates hellishly noisy and soul destroying data.

@Martin - My OIII data is always quite grainy, but in a bi colour and blurred to hell and back it doesn't matter!!! :D

Link to comment
Share on other sites
PhotoGav

PhotoGav

Posted
Posted

Good, I'm glad to hear that the noise discussion is an interesting one!

I totally agree with Olly in that visible NR is too much - those patches of over smoothed background are just not art at all! A degree of noise seems to be inevitable and it does add an analogue realism to an image anyway. Surely the cloudy patches of space that we love to image are full of speckly bits that will show up in our images and really are dusty 'noise' rather than generated noise?! Processing an image is a very personal thing and, as you say Sara, the onlooker (what a lovely term for somebody viewing a work of art, as they kept on using in 'The Painting Challenge' recently) sees the image in their own unique way, so it is virtually impossible for these images to be 'objective'. Their purpose is to display the beauty of what we can see in Space and, Sara, your image, whatever the noise level, does that spectacularly!

Where next in Space for you?!

Link to comment
Share on other sites
swag72

swag72

Posted
  • Author
Posted

Nothing exciting in the pipeline I'm afraid Gav. With Galaxy season under way looks like I'm going to have to do my nemesis of LRGB imaging. Daft of course as the moon effectively wipes out 2 weeks of imaging when you do this 'normal way'

Link to comment
Share on other sites
PhotoGav

PhotoGav

Posted
Posted

Thank goodness Earth only has one moon! I think this should surely influence humanity's search for a new planet to live on.... I'm voting for a nice dark planet with no moons at all and ideally very little in the way of cloud cover too...

I digress from the OP somewhat...

Happy Easter everyone!

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.