First ever shot of the night sky - pls be gentle :)

[stardotstar (Will)]

Hi all,

I pointed my EOS40D at the sky last night (Turramurra Sydney) facing roughly ESE (I think) and with the tripod/camera tilted at something like 70'.

This is what I got - I basically framed the brightest point - I thought Mars or Venus (though I made no attempt to id anything that would be there - and my knowledge is very basic so please be gentle)

Here is the camera data:

EOS40D
2009-07-17T23:47:25+10:00
Shutter Speed 5.2 sec
Exposure Prog: Aperture Priority
F-Stop:f/5.6
Aperture Value: f/5.7
ISO Speed Ratings: 250
Focal Length: 135mm

I suspect with some more details (or what I have provided above) the gurus here will know exactly what the red fringed object is - and can anyone tell me if the suspiciously spherical blue/green "aberation" top right (I cropped the whole frame to the diagonals of significance) is a lense distortion or chromatic aberation or something?

I look forward to following your leads in capturing some images of the night sky and would appreciate any help in ID'ing this first shot of mine.

There being no moon to shoot that is what I pointed at and came back with

Best regards,
Will

[bird (Anthony Wesley)]

Hi Will, based on the time you took this, I suspect the bright object in the lower left is Jupiter, although it is out of focus you can see one of its moons close by.

Getting good focus with a DSLR is not easy, you'll have to look into some of the focussing software that people with those cameras use.

cheers, Bird

[stardotstar (Will)]

Wow, that is incredible! I can confirm that it was SE - around 100', checked just now.

Top right is a lens problem?

Not sure if my lens is going to cut it from a focusing pov - i set it to mf and tried to resolve it to infinity - but it is very hard to tell based on the feel of the lens ring and without any visual cue...

Much to learn.

BTW this lens is a 28-135mm - pretty standard lens with the 40D. So I guess I will be thinking about the right sort of lens for this kind of thing if I can make some progress!

Thanks so much for the reply- very exciting if it was Jupiter and a moon!
Will

[stardotstar (Will)]

I hope this is ok since I am new to the forums here.

Here are links to two of my images (the same shot)

This one I have done some level adjustment with photoshop to enhance objects of the kind of spectral output of the bright red "moon".
http://www.sourcepoint.com.au/outlin..._uncertain.jpg
This has allowed me to circle several other very similar objects. If I resolve in the red any further I get a lot of noise but the circled ones are definitely destinct from the film noise...

It would seem too that the blue spots are lens artifacts probably caused by the brightness of the main object.

Secondly this is the original image without any cropping or adjustment.
http://www.sourcepoint.com.au/outlin...03_24_5782.JPG
(nb ~ 3MB)

[renormalised (Carl)]

It was probably Jupiter you imaged there, but it's quite a bit out of focus. I have a feeling that red dot off to its right is a hot pixel and not one of the moons, but a bit of careful observation and maybe a bit of pixel jiggery pokery might resolve that question.

[Kal (Andrew)]

The 40D has liveview?

If it does you should use it to focus. I'm not sure if it would be the same as the 1000D I have, but you first focus a bright star, use the zoom and centre it and focus again, then zoom in again (10x zoom) and centre and focus again. Should give you spot on focus.

[bird (Anthony Wesley)]

Not sure if its Jupiter, just noticed that Will said he was looking to the SE, but Jupiter would have been in the NE.

However if he was pointing at the brightest thing he could see, as he indicated in the original post, then it would have been Jupiter, in the NorthEast.

cheers, Bird

[stardotstar (Will)]

Intriguing guys.

Just checked again now with a traditional magentic compass - rather than the iPhone
It is indeed North East - probably between 60 and 80'.

So that seems to confirm it was Jupiter?

Yes the 40D has live view - in fact I was using that to frame up.

It seems that I have much to learn even to get the camera to focus to infinity.

That's right isn't it - the focus should be set to manual focus, zoomed in to the max centred on the object and then the focus ring wound out to infinity.
Kal, I will try to follow your suggestions. I take it that you are using auto focus and centre spot focus selection. (gotta get the bloody manual out I think )

I will have another play tonight after ensuring that the lens is super clean and the recommended exposure settings and what not are pre configured.

Will

[renormalised (Carl)]

Originally Posted by bird

Not sure if its Jupiter, just noticed that Will said he was looking to the SE, but Jupiter would have been in the NE.

However if he was pointing at the brightest thing he could see, as he indicated in the original post, then it would have been Jupiter, in the NorthEast.

cheers, Bird

That depends entirely on where you are. From down your way it would be NE, but from where I am it's more ESE/SE. Then again I am something like 16 degrees north of where you are

[Kal (Andrew)]

Originally Posted by stardotstar

Kal, I will try to follow your suggestions. I take it that you are using auto focus and centre spot focus selection. (gotta get the bloody manual out I think )

I normally have a scope on the camera and have to use manual focus.

Another method to get focus right is to manually focus it on a distant object in the daytime, such as a tree or telegraph pole which is far away (several hundred meters away). I'm not sure if manually setting it to infinity focus will bring out the best results