Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: MarkS on Feb 20, 2008, 22:24:02

Title: Another Mars
Post by: MarkS on Feb 20, 2008, 22:24:02

Taken Sunday evening (17 Feb).  SPC900 webcam on the C11 with 2 barlows.  96 frames of 0.2sec stacked using Registax and then wavelets applied.

(http://homepage.ntlworld.com/the_shelleys/photos/mars17feb.jpg)
Title: Re: Another Mars
Post by: Whitters on Feb 20, 2008, 22:37:54
Top shot Mark, And that disk is so small at the moment. Excelent
Title: Re: Another Mars
Post by: MarkS on Feb 21, 2008, 07:07:10

Cheers Paul.
Title: Re: Another Mars
Post by: JohnP on Feb 21, 2008, 09:43:07
Great image size Mark - I think you are brave even trying this seeing how damn small it is.....
Title: Re: Another Mars
Post by: Ian on Feb 21, 2008, 10:11:00
there seems to be a salmony sort of coloured edge on the left hand side. Have you tried aligning all of the colours? You'll find mostly rubbish in the green and blue channels on a Mars image though.

But, now without being picky, fantastic image. :)
Title: Re: Another Mars
Post by: MarkS on Feb 21, 2008, 12:36:08
The salmon colour?  There are vast lakes of flamingos on Mars which can be seen from space.

Seriously though, I really have no idea.  The colour registration is fine.  Possibly the red channel became saturated somewhere during shooting or processing  - would that cause salmon?  Tonight  I'll review my processing sequence - if I can't find the cause I'll post the original (after stacking but before wavelets) so you can play with the image yourself.
Title: Re: Another Mars
Post by: Ian on Feb 21, 2008, 12:52:23
of course, everyone knows flamingoes are that colour because of the shrimps they eat. And they said Mars was too salty for life...

I couldn't work out where that was coming from either, but the pole is the same sort of colour.

It could just be that's the way it is right now.

One big fish farm.

with flamingoes.

and feather boas.

what were we talking about again?
Title: Re: Another Mars
Post by: JohnP on Feb 21, 2008, 17:32:28
Ian - You been taking something again.....? Mannnnnn!
Title: Re: Another Mars
Post by: MarkS on Feb 21, 2008, 20:04:16

I can't work out where the salmon came from but I probably haven't post-processed it optimally.

Here is the raw stacked image from Registax (cropped to 256x256) for anyone who wants to have a go ...

http://homepage.ntlworld.com/the_shelleys/photos/mars256.tif (http://homepage.ntlworld.com/the_shelleys/photos/mars256.tif)
Title: Re: Another Mars
Post by: Tony G on Feb 22, 2008, 13:52:52
Great image Mark. ;)

Tony G

Title: Re: Another Mars
Post by: Ian on Feb 22, 2008, 14:16:00
I've had a look at it, and I think that border of a fishy hue has come from the blue channel. Unfortunately, the blue channel have almost no data in it at all (which is usually the case for a mars shot). I'm now trying to synthesise a blue channel to help with the colour balance...
Title: Re: Another Mars
Post by: Mike on Feb 22, 2008, 16:26:58
I like salmon. Leave it in.
Title: Re: Another Mars
Post by: MarkS on Feb 22, 2008, 17:40:41

You're right Ian.  There's something strange about the blue. Maybe the answer is to do wavelets on the red & green and just leave the blue as it is.
Title: Re: Another Mars
Post by: MarkS on Feb 22, 2008, 20:33:02

That seemed to help - leaving the blue channel without a wavelet transform:

Before & After:

(http://homepage.ntlworld.com/the_shelleys/photos/mars17feb.jpg)(http://homepage.ntlworld.com/the_shelleys/photos/mars17feb4.jpg)
Title: Re: Another Mars
Post by: Fay on Feb 22, 2008, 21:44:13
Mark, all your images have usually been captured amidst a lot of calculations & workings out, trying to find out what is the best you can get out of your equipment at 5am in the morning!

If you had been around quite a few years ago, I think you would have been one of those with false wings on trying to master flying or trying to ride across the Sahara on a push bike, to see if it was possible, or climbng Everest without oxygen to see if you could do it!

Before you all ask, I have only had a couple!!!!!!
Title: Re: Another Mars
Post by: Whitters on Feb 22, 2008, 21:59:49
of bottles  ;)
Title: Re: Another Mars
Post by: Tony G on Feb 22, 2008, 22:48:18
Of 98% surgical spirits. :)