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niko
30-04-2007, 04:50 PM
I'm in the process of purchasing a Celestron SLT130 from a IIS member and wonder if anyone had any advice regarding using it for planetary photography.

Will it support the weight of a camera, am I limited only to CCD/webcam use?

Is it's "seeing" capacity just too limited? Will it be okay for planets? How about the brighter DSOs? Jewel Box etc...

Any advice GREATLY appreciated!

many thanks

niko

[1ponders]
30-04-2007, 05:34 PM
While I can't comment on the scope itself, being Alt/Az mounted you won't be able to do long exposure photography unless it can be modified to an equatorial mode. You would have no problem though with a webcam and planetary, Luna or solar work, but as it only has a native focal length of 650mm the image will be small, even barlowed.

iceman
30-04-2007, 07:36 PM
As Paul says, it won't be good for deep-space stuff but for planets/moon it will be good. The image scale will be small though.

Get a ToUcam 900nc and see how you go! Let the learning curve begin!

niko
01-05-2007, 08:04 AM
Thanks for the feedback guys.

As I'm using an 8" dob at present I'm prepared for the loss of visual quality but thought it was a good place to learn how a Goto set up operates.

Am I missing something though? Comment was made by 1pounders that it is a Alt/Az not equatorial mount. I thought a Goto system was an eqatorial setup and I could therefore use it to track objects as they move across the sky. Thus opening me up to the world of Registax etc.

Am I missing something or being dim?

thanks

Omaroo
01-05-2007, 08:35 AM
Hey Niko - Go for it. It's all fun. My wife uses a 130mm reflector when she gets time, and although it isn't a patch on our larger scopes for detail, it's a lot easier to carry around. One thing you might do with it is get it to carry a laser - and use it's GOTO function to point the way for your larger scope until you get to know the night sky.

Cheers
Chris

Kal
01-05-2007, 11:56 AM
Goto setups can be both alt-az and equatorial. The celestron that you have, just like my LX200, is alt-az. To make it equatorial you will need a wedge of some sort.

The only difference between alt-az and equatorial is that you will get field rotation if you try imaging anything deep sky in alt-az. Quite often though, for any deep sky imaging the mount is more important than the scope, as you need very accurate tracking. With planetary imaging however, tracking is not important because your exposures are only a fraction of a second each.

[1ponders]
01-05-2007, 11:59 AM
Niko, it has to do with how the scope is mounted. Either Alt/Az or Equatorial can be goto and tracking mounts.

If a star is east of a line drawn from north to south (meridian) then an alt/az will track that star by moving west then "up" continually. Once the star moves past the meridian the mount will move west then "down". You will not notice this visually. But if you are imaging then you will get "field rotation". ie all the stars in the field will rotate around a central point. To do DSO imaging with this sort of scope you need a way to "polar align" it and this is usually achieved by using some form of equatorial wedge that tilts the mount head to the angle of your latitude.

An equatorial mount is set up to point directly at the south celestial pole (raised at the angle of your latitude) and when it tracks a star it does it only in one axis which will follow the star smoothly across the sky in an arc. You still need to guide to keep exactly on the star but you wont have field rotation (assuming you are polar aligned well).

Does that make sense?

niko
01-05-2007, 12:35 PM
Very much appreciate the advice and comments - thanks so much.

I sure have a lot to learn still!

Omaroo - good comment, had certainly thought it would help with object identification.

Iceman - hope it is a bell curve and not a J curve!!!

Kal & 1pounders - thanks for the lesson in mounts - made much sense and has helped illuminate the darkness!

I can see light at the end of a long tunnel, I just hope it isn't a train!!

thanks again