I set the 10" up last night with the intention of getting some images of Saturn and decided to fill the time before Saturn appeared by imaging some interesting galaxies. Being so close to Brisbane there was quite a bit of sky glow to deal with but I'm quite happy with the results.
Unfortunately when Saturn finally appeared so did the clouds and judging by the weather forecast it looks like it will be the new year before I'm going to get another try.
All images are 50x1 min subs using the 10" Newt guided on the EQ6 and the DSI II pro.
As always there's still a lot to learn - comments welcome. Thanks for looking (and for the company Allan).
I hope you dont mind my doing so, but I had a quick play with 1365 in photoshop.. stretched it a little more, maximum entropy deconvolution (very low settings) and a tiny touch of noise reduction..
I dont know if its "Better" but its easier to see the detail in it now!
Alex
Edit : hit it with gradientXterminator too... uploaded again...
good work. I can tell focus was spot on as you have resolved some great detail there. I also agree that they are a little dim. In Photoshop, duplicate the background layer and in that second copy, make a selection around the core of the galaxy, and feather it by 15 pixels or so. Select 'Inverse'. Now add a curves adjustment layer. Click ok without making any adjustments. Then right click on the curves adjustment layer and select 'Create Clipping Mask'. Now,click on the curves icon in the adjustment layer and make your adjustments carefully. You will bring up the brightness of the outer arms and background without burning out the core of the galaxy.
Now, merge down the curves adjustment layer with the background copy layer, and adjust opacity of that layer to get just the right finish. Now flatten.
Thanks for the comments and suggestions Alex, Marc and Martin. I tried the routine you suggested Martin (after finally working out the correct section of the curves adjustment layer to right click on to make 'Create Clipping Mask' appear) however I'm finding the background (gradient) becomes very prominent. Is there a way to remove this without GradientXterminator?
raising the black point in levels can remove the gradient, but at the cost of also losing some of the fainter areas in the outer arms of the galaxies..
You could try selecting the galaxy, expand and feather the selection and then brighten the galaxy... Then, invert the selection and raise the black point for the background sky...
I've never tried this, but in theory, it should achieve what you are looking for.
Thanks for the comments and suggestions Alex, Marc and Martin. I tried the routine you suggested Martin (after finally working out the correct section of the curves adjustment layer to right click on to make 'Create Clipping Mask' appear) however I'm finding the background (gradient) becomes very prominent. Is there a way to remove this without GradientXterminator?
There are a number of techniques to remove gradients if you google around. If it's a color gradient the imbalance can be corrected directly within the color channel.
Interesting point - I checked out the distances and they are all similar (give or take 10 million ly's.
NGC1365 65 million ly (extends 200,000 ly)
NGC1097 53 million ly
NGC1566 51 million ly
I selected these based on an astroplanner search sorted by angular size and magnitude. Judging by the image scale in the pictures I guess that means they are all similar in actual size?
Interesting point - I checked out the distances and they are all similar (give or take 10 million ly's.
NGC1365 65 million ly (extends 200,000 ly)
NGC1097 53 million ly
NGC1566 51 million ly
I selected these based on an astroplanner search sorted by angular size and magnitude. Judging by the image scale in the pictures I guess that means they are all similar in actual size?
To better measure the actual size of the galaxies, given their angular size, just use the small angle formula and plug the variables into the equation. That way, you'll get a better approximation of their size, rather than relying on the image scale, which is normally deceptive.
Excellent panel of galaxy images Peter. Sure they look a little unstretched, but all the qualities are there with good detail on display. Thanks for sharing.
Cheers Jase - not sure how to stretch much more without the background skyglow and noise becomming prominent. I've spent a number of hours playing with ps but still a lot to learn - any ps tips much appreciated.
Merry Xmas Peter - three lovely shots and I like how you have held the detail in them. Love to see them whem you have had a go at processing them further
