M27 with fuzzy bits

[johnh]

Wonderful M27 with very long subs showing extended gas coming out further than I have seen before and looks 3D like a well.

John.

[evilgeenius]

Brilliant!

What did deconvolving the image do? I don't hear much about it, so I'm not sure what it does for an image.

[MartinB]

Brilliant!

What did deconvolving the image do? I don't hear much about it, so I'm not sure what it does for an image.

Deconvolution is a sharpening technique employed before any other processing has been done on an image. The theory is that stars should be pin points of light of almost infintesimal diameter. The fact that they aren't is down to atmospheric distortions, optical aberrations and so on. By looking at the brightness profile of a star pixel by pixel deconvolution aims to calculate the correction required to turn it back to a pin point. If this calculation is applied to each and every pixel in the image it should lead to a perfectly sharp Hubble style image!

Unfortunately there are too many random irregularities involved so deconvolution is never as perfect as it sounds. There are lots of deconvolution algorithms e.g. Lucy Richardson, positive constraint etc etc. Many imaging applications have a deconvolution routine, some better than others. I like to use CCDSharp's positive constraint routine. Normally the deconvolution is done in stages iteratively, too few iterations and you don't see a difference, too many and the image is mangled. It's a tricky tool and slow to run because of the huge number of calculations.

[evilgeenius]

So you modify the whole image based upon the distortion found in just the stars? Does this improve definition in other parts of the image, such as like the gasses around your m27, or is it just for improving the stars?

[Steve]

That is astonishingly good Martin, right up there with the very best! Under British skies too

[blinky]

WOW Martin, that's simply stunning, the AO unit worked a treat - 10 corrections a second.......

[Rossco72]

Looks good, can't remember seeing so much nebulosity on M27 before.

Congratulations on a wonderful image.

[MartinB]

Thanks Steve, Craig and Rossco

So you modify the whole image based upon the distortion found in just the stars? Does this improve definition in other parts of the image, such as like the gasses around your m27, or is it just for improving the stars?

The star profile is used because it is a pin point. It provides what is know as a "point spread function". The sharpening is applied to the whole of the image and often works very well regions of gaseous nebulosity. You have to keep an eye out for artefacts developing though.

[Vali x]

Congratulations mate

[BobinKy]

Great image. Thank you for sharing.

...Bob

Kentucky