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Zuts
15-05-2007, 01:02 AM
Hi All,

My second attempt at Jupiter. The first was a fuzzy blob.

Nexstar 11,

Eyepiece projection (11 mm)

0.8 s on 300D

Should i go for more than 0.8 seconds, None of the moons came out?

nightsky
15-05-2007, 02:09 AM
G'Day,
Nice one M8 :thumbsup:
Cheers
Arthur

iceman
15-05-2007, 06:48 AM
Excellent work Zuts! The exposure looks good! To get the moons in picture, you'd need a longer exposure, but by doing so, you'll overexpose Jupiter.

So take 2 exposures - 1 for Jupiter and 1 for the moons, and then recombine them in post-processing.

Here's a quick crop/process/resize of your image. Very well done.

Zuts
15-05-2007, 07:29 AM
Thanks Iceman,

Thats the best of a few images. I took a number while making small increments to focus. What a great idea about the moons i would never have thought of that. Lol, maybe i should by a book....

Still it looks very fuzzy. Have i still got the focus wrong or is there some other means of getting better details, with a 300D? Would multiple images help?

Possibly there were some leaves in the way as it was taken through a tree, or is it the seeing or my focus still.

Also how can i work out the magnification with a 300D in the optical path. Is it still roughly Ftel/Fep?

Lots of questions :)

Thanks for looking
Paul

middy
15-05-2007, 07:32 AM
That looks great Zuts. You may not have captured a moon but it looks like you caught a moon shadow. :thumbsup:

[1ponders]
15-05-2007, 08:05 AM
It is always going to be difficult getting a good sharp image of a planet with the DSLR. Your exposure needs to be long enough to get detail, but unfortunately the seeing over that time frame (in your case nearly 1 sec) will cause the image to smear. You could go for a higher ISO (800 or more) to try to reduce the exposure time to 0.2 to 0.1 sec. That will help with the seeing. You can then try to get multiple images to stack. I used to try this when I first bought my 300D. I soon gave up and bought a webcam :P.

The advantage of the webcam is not that it take images at short exposure but that you can collect hundreds of images in a very short period which you can then stack. It is the stacking of many many images that brings out that magical detail.

Zuts
15-05-2007, 08:31 AM
Thanks 1Ponders,

I will try a bit more and as you say, for planets will probably move to a webcam. I would really love one of these

http://www.optcorp.com/product.aspx?pid=319-320-1048-9300

[1ponders]
15-05-2007, 08:44 AM
Looks very tempting ;)

jase
15-05-2007, 09:35 AM
Nice work there Zuts. Good to see you're putting the NX11 through its paces. Looking forward to seeing more of your work.:thumbsup:

[1ponders]
15-05-2007, 09:59 AM
In the meantime, do you have a T ring adapter for your camera to attach it directly to a scope? If you do you might want to consider one of these for your eyepiece projection, it will make life a lot easier for you. You won't have to keep trying to line the camera up with the eyepiece all the time.

You drop an eyepiece (15 - 20 mm, orthoscopics work really well) into the variable extender and secure it using the bottom screw (not visible on this shot. It is on the other side). You then screw the large end into the camera T adapter. The bottom end then screws into an SCT to T thread adapter that attaches to the back of you scope (or a primefocus adapter like the second photo). This setup allows you to vary the amount of magnification you can achieve simply by either sliding the adapter back further or inserting a shorter eyepiece. It's a great way to get EXTREME focal lengths. Way too much actually at times, but you won't be able to help yourself ;) . Great for moon shots as well.

If you check out the diagram you will see what I'm talking about. The only difference is the the extender I am using/talking about is variable rather than fixed like the one in the diagram.

[1ponders]
15-05-2007, 10:01 AM
BTW there are cheaper ones than the meade one.