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skwinty
21-03-2008, 08:48 AM
Hi All
My first relatively successful image.
Focus and tracking still need improvement, but the first I am prepared to show any one.
Looks like I got two satellites in the shot as well.
Scope 12" Newtonian
FL 1520mm
Canon 40DH at prime focus.
Shot in raw.
Exposure 20 by 10 seconds, summed in AIP4WIN as tiff as AIP4WIN still does not handle 14 bit raw correctly(even after upgrade, treats as 12 bit).
Saved as jpeg to bring size down to 400k. Zipped to comply with forum limit.
Left quite large size to show satellites.
Will try in future to keep below 200k.
Taken from my light polluted backyard in Table View.
Thanks for looking and constructive criticism.:)

OneOfOne
21-03-2008, 08:56 AM
I always find it amazing that you can be looking at a piece of the sky the size of a match head for a couple of minutes....and a satellite goes past! You were "lucky" enough to get two :) There must be so many of those buggers up there.

skwinty
21-03-2008, 08:59 AM
Makes me think of a galactic rush hour.
I often wonder how many tons of man made objects there are up there:)

sheeny
21-03-2008, 09:31 AM
G'Day Steve.

Not a bad first image... is the red glow in the bottom right hand corner light pollution or amp glow? I suspect it's light pollution - it seems a lot for amp glow on such short exposures. The image seems a bit red, but you'll gte the hang of colour balance as you go;). Focus needs some work too as you noted.

Are you sure they are satellites? They don't seem to move very far between shots (very slow apparent motion) but I can't think what else they'd be:shrug:.

Looking forward to more...

Al.

Alchemy
21-03-2008, 10:29 AM
GDAY squintz.

I have aip4win and just got the upgrade notice the other day and havent done it yet, but i did find deep sky stacker a better program for stacking, personally i use median most of the time to stack, others have their favorites but this will remove the satelites if you want.

do you have any guiding capability? if not you will find this will severely limit future harder targets like galaxies and such, as tracking will deteriorate over time.

Finally well done on your very first image for this department.:)

Hagar
21-03-2008, 10:50 AM
Nice image. Still a little work to be done on your polar alignment but you are definitely getting there. Well Done

Dennis
21-03-2008, 03:11 PM
Good work Steve – you’re certainly jumping in at the deep end with a focal length of 1520mm. A little elongation due to tracking or polar alignment but you’ll fix those up quickly no doubt.

Congratulations on your 1st light – it sure is a magical moment. There is a lot of work behind what you have achieved, well done.

Cheers

Dennis

skwinty
21-03-2008, 06:06 PM
Hi All
Thanks for looking and your comments.
The glow at the bottom right is the light coming from the telly. Wife watching fave program and wouldnt switch off. I was just outside the door leading to the living room. I did no colour correction or any other tweaks. just summed the 20 images.:)
I am not using any guiding yet but will splash out soon and get some more gear.

Matty P
21-03-2008, 06:51 PM
Great first light Steve, well done.

Looking forward for more.

cwjames
21-03-2008, 06:55 PM
Hi Steve,

Grats on your image of the Jewel Box. Images of it seem to be hard to find.

I took a image of it last weekend, but something went wrong and I was trying to find others to compare it to to understand what I did wrong.

I think mine is out of focus !

http://www.cwjames.info/astro/gallery/starcluster/starcluster-003.php

Looking at your I will try doing it again when I have the scope in that area of the sky.

Thanks for sharing.

Chris

skwinty
21-03-2008, 07:26 PM
hi Chris
the stars do look a bit bloated which could mean focus is out.
However your tracking looks spot on to me.
What are the details of scope focal length camera exposure etc.
Colours look good.:thumbsup:

cwjames
21-03-2008, 07:57 PM
Hi Steve,

Yep the guiding and Drift Alignment was ok, I think the mirror on the LX200R must have moved after doing the focus. Or I never had it focused correctly at the start. I am going to do a mod to the LX200R to improve the focus, however I think I was at fault by not checking it closely on the night.

Setup is:
Main scope is LX200R with 20D Canon DSLR at prime focus.
Guide scope was SkyWatcher ED80 with meade DSI for quide CCD.
Exposure was 8 x 240 Seconds

Just a pitty we where out of focus, try again another night I guess, I was supprised by the blue and orange stars in this cluster.

Se Ya
Chris

skwinty
21-03-2008, 08:10 PM
Hi Chris
thats what I like about this hobby.
We can only get better;)

skwinty
22-03-2008, 07:08 PM
Hi All
Some more pix from the same evening.Processed yesterday and sorted the jpg conversion size.
On the jewel box pic, if you zoom in (ignoring the poor focus and tracking) you will see three and not two satellite trails. I think they are satellites but I suppose could be something else.
Comments welcome:thumbsup:

iceman
25-03-2008, 05:08 AM
Well done Steve, great to see you getting images finally!

How long were your exposures? I don't think they're satellite trails - because they're not trails! It looks to me like a dead pixel on the CCD.

skwinty
25-03-2008, 07:13 AM
thanks Mike
Took quite a few more this weekend albeit with a full moon.
will post as soon as processed. At the moment I am experimenting with the different effects of summing, average, median and sigma clip average.
So much to learn but loving the challenge.
The exposure time is 5 sec and summed 20 of them.
I have noticed these "trails" on one or two other pics but in different places.
Could it be that its not dead pixels but a dropping off of pixels during read out. If you count them they are the same number as exposures. What would a satellite trail look like on a 5 sec exposure with a 5 sec gap between exposures.:thumbsup:
ps would a dead pixel not be black rather than white?

Zuts
25-03-2008, 07:55 AM
Hi Steve,

Nice photos.

I think iceman is correct, they are just stacked hot or dead pixels. These should dissapear with using darks. Even a 40 D on a five minute sub will result in 100's of hot pixels, all of which can be removed using darks. Some vignetting is obvious as well so you will need some flats (not that I should talk about flats :)).

Failing darks, just use the healing tool is PS.

A satelite trail looks like that, a continuous line across the field of view.