Struggling to figure out how to use by Dobsenian

Hi everyone…I recently bought a 12 inch skywatcher goto dobsenian scope. Just not able to figure out how to watch planets. The best I could do is looking at the moon :pensive:. Below are the eye pieces that I have.

  1. 0.10 mm
  2. 0.25 mm
  3. 0.42 mm
  4. ED Barlow

Can you please elaborate on why you are not able to observe the planets?

Frankly I don’t even know which eye piece to use and how to focus

Enclosing the picture with the eye pieces that I have

Since you have a go-to system, once it is set-up and aligned, you can dial-in the target (say, Jupiter) and then telescope finds it for you. Use the 42 mm eyepiece first since it has the largest FOV to make sure the object is centred in the FOV of the eyepiece. Then you can change eyepieces or add a barlow to achieve a higher magnification. And you have to refocus whenever you change eyepieces or add a barlow.

At first I am doing an alignment based on moon. Once my alignment is successful, later I am asking the hand held device to focus on Jupiter. However once the telescope moves towards Jupiter, I am not able to find it. I even try to manually search. However no luck

Jupiter is a bright planet. It is visible to the naked eye. Try manually finding it with the finderscope of your telescope and then look into the eyepiece (use the 42mm). Your finderscope needs to be aligned with the telescope’s view for this to work. Apps like stellarium, skysafari etc., will help you to find the general position of your target.

Use the sky guide app to find the planet coordinates, and then use the telescope and zoom into them. The sky guide app is one time payable 179 INR. But it’s worth it. It gives you an idea of the coordinates and a virtual presentation of them in the app. All the best.

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Here’s what I would recommend.

  • Use it manually for now.
  • Center the moon with your finderscope and see if it’s visible in your eyepiece. I would recommend starting with the 42mm eyepiece for now.
  • If it’s not in the center, align the finderscope. This step is very important. Make sure the finderscope and your eyepiece are perfectly aligned. You can change eyepieces and ensure the centering is perfect even in high magnifications(your 10mm eyepiece can be used for this).
  • After this, try spotting Jupiter with your scope. Again, center with the finder and then use the eyepiece.
  • Once you get comfortable with this, start using higher magnifications.
  • After this, try the go-to functionality. I believe the finderscope is not aligned and that’s causing all these issues.
  • If you are still facing issues, do reply and I will help you accordinhly.
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