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NGC2237 Rosette Nebula - ** HOLY COW! **


SteveL

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Very nice work, deep and detailed and all in just one hour. :shock: :shock: :D

Looking forward to more stunners from your new setup. :rolleyes:

One thing, not a criticism just just a matter of personal taste really. On the large image I noticed that the detail looks a little unnatural, I am not sure what it is but something (maybe too much deep space noise reduction) is giving the image a blotchy feel.

Like I said it's really down to personal preferences, IMO a little more noise in an image is OK if it helps preserve the natural feel.

Mike.

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The diffraction spikes work well, what is causing them?

The spikes are being caused by the camera and associated cables sticking out the front of the corrector plate. I`ll be posting a review later

Ah. Which is why they look 'uneven'.

So, how do you / can you overcome them?

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Running out of superlatives here :D:rolleyes:. You keep moving the goal post Steve :?.

Personally I think the diffraction spikes look OK at first glance you wouldn't notice any asymmetry.

I wonder if it would work better with a Starlight Express CCD which is about the same diameter as the central obstruction?

Also I think youre image stands out a mile from most on the Hyperstar website.

Regards

Kevin

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After the excitement had worn off from my first light, I had the chance to take a closer look at the images the Hyperstar had spat out. One thing that stood out was that the stars were always big and blobby, and detract from the DSO itself. After trying various different ways to reduce the star sizes (without much result!), it was a comment from Noel Carboni on another forum said that triggered a little lateral thinking. Up until now I have always processed my images as one, but if I wanted to reduce the star sizes, I needs to work on the stars as a seperate entity. I had a play with this idea quickly last night, and the results from those briefs tests showed some real promise.

As such, I have just soent my lunchbreak reworking my original image from scratch, and here are the results.

First off, the original I posted above:

ngc2237_rosette_cls_20x180s_small.jpg

and now the reworked version from today, with much smaller stars:

(Click on image for the HUGE version)

ngc2237_rosette_cls_20x180s_wip4_small.jpg

Personally I like this version much better. The stars are still there, but far less obtrusive. I would like to hear feedback and comments on the new version, especially about the star sizes... are they now too small? I can increase them with my new and improved process, but I`m just testing the water... I like small sharp stars when they are the background to a DSO.

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i wont comment yet Steve as this monitor at work is carp, but i,m with you as far as the stars go , its a personal thing i guess , i know a lot of ppl like to see the stars , i think thats fine for clusters etc and small wide field DSO work. for this type of image i prefer like you to do a layer and reduce the stars to 1 pixel and use about 50 to 60 % on the opaque.

then i can control the star brightness by using a fine tweak on the contrast.

As far as i can see on this monitor Steve ,it looks like some data has been taken away from the second image ,although the second is smoother, i prefer the first image for the rosette ,but the second for the stars , hells bells now thats given u some thought , but i will have a better look at home .

Rog

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Hi Steve,

I too like small stars (difficult to get with my sampling rate!) but the problem with star reduction after the event is that the rest of the image loses contrast and I feel that has happened with the your second image - the lovely clarity of the original has gone, even in the dark background sky. It is still a fine image but I prefer the original as it just looks so bright and un-muddied.

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I think the difference in the DSO is the levels and curves are screwed... it will require another rework to get them sorted, but it was mostly an exercise for star size reduction... the loss of contrast and brightness in the DSO itself is due to me being sloppy :D

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I think the 2nd is a lot better (When viewed full size ).

It, more than anything else is miles more natural looking also better colour and no dark halos around the stars.

Great rework Steve.

P.S I like the stars in the 2nd also. :D

Mike.

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God Steve thats rubbish..... :rolleyes: :rolleyes: {massive leg pull... obviously}

Gobsmacking work...Would love to have seen your face when that eventually appeared on your screen!

I tried to find a picture of a cow with a halo on it's head to go with the thread... no joy :D.

Matt

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well now i am home and on my super Monitor , i can now see all three images nicely , have to say Steve and its only my opinion, that the last process to me looks the business, just one thing that could improve it on my screen anyway , and thats to lasso the centre bright part and just tone down that section , this would bring the detail out more , thats it really a splended image .

Rog

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Christ almighty ! (Sorry mods) but I can't think of anything else to say after seeing this one. I've watched Steve go from really impressive images, to this almost godlike image in just a few months. It is incredible what you can do from your backgarden my friend. I am so very, very impressed. It is a privelidge to view every one of your pictures.

Keep it up and Nasa can retire a space telescope or two.

JV

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You can go on for ever with this Steve and it becomes impossible to see the wood for the trees. I think the nebula on the first image was spot on. The stars were a little prominent so benefit from a bit of a tone down but when you go too far they look attenuated and, for me, the image looses it's vibrancy. The nebula in the 1st image looked great from a distance but close too the sharpening artefacts were quite noticeable.

That last image is spot on and worth the extra effort

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I am sure no one minds Steve. We are not going to get tired of seeing this Nebula.

The main structure, which actually consists of various parts, embraces the cluster NGC 2244, which is embedded in the nebula. Herschel never saw the nebla at all when he discovered the star cluster. I have just compared an Image of David Malins with this, taken with the Anglo Australian Telescope, and I can't tell the difference. The area of the Rosette Neb, is 80x60 arc minutes. The cluster NGC2244 is 24 arc minutes which is less than the diameter of the full moon. When you take your eyes away from the main feature, and look at the numbers of stars, abounding in this relatively small area of space, it just confounds the senses. It is just that I am thinking out loud , and wondering if we are ever going to understand what is really going on around us, as we stand on this microdot of ours.

I am not throwing a wobbler or anything, It's just a curiosity I feel that is never going to be satisfied.

I suppose the best thing is to enjoy it and not think about it.

Ron.

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