Getting started with Skywatcher 130p flextube

[ashish83]

Hi,

I am a newbie to stargazing and recently bought Skywatcher Heritage 130p flextube telescope. I have aligned the RDF finder and was waiting for clear skies to give this scope a go. Yesterday, I tried to view Jupiter and Saturn with it. They are visible from my bedroom window just over the roof of another house and behind a street light. I tried to view them with both 25mm and 10mm EP but could not see any details. They were looking just like a bright dot. I was watching through a glass window as the view is obstructed by houses from my garden.

Just wondering what is the best way to see some details on these planets. Should I use 25mm or 10mm EP? Can it be an issue with collimation? Me and my son would love to see the rings of Saturn if this is possible at all with my current set-up. Or do I need a barlow and some filters to find out more details on the planet.

[AstroMuni]

Welcome to SGL, ashish83.

You should be able to see the rings of Saturn and bands on Jupiter + moons with that scope. It should be visible with both those EPs w/o Barlow. Watching through a glass window could give you blurry views and double images. So if you can open the window and see that might help.

I am guessing that the EPs are the stock EPs that came with the scope. Using a 2x Barlow with 25mm would effectively get you a FL of 12.5mm. Using it with 10mm Plossl would make it harder for you to keep track of the planets as they move about. But you can always try 🙂

Where are you based?

Edited July 24, 2020 by AstroMuni

[ashish83]

Thanks for replying AstroMuni.

Yes the EPs are the one supplied with telescope and the planets were moving out of focus very quickly with a 10mm eyepiece. So would you recommend to use 2x Barlow with 25mm eyepiece to get better view?

I am based in Glasgow. I read somewhere that open window can cause more trouble because of warmer air inside the room. Is that not correct?

Edited July 24, 2020 by ashish83

[-chris-]

Hi ashish83

I have the heritage 130p and I'm also a newbie.

I have seen both Jupiter and Saturn using the stock eyepieces. 

The only things I can say are:

You really need to be outside, viewing through a closed window will distort the view and the heat from inside the house when viewing through an open window will also distort the view.

Let your eyes adapt to the dark and let your telescope cool to the outside temperature, this will let your eyes see more detail, so will spending more time looking through the eyepiece at your target.

Using the 25mm first then using the 10mm is one way to do it but the 10mm isn't the best eyepiece (it can be done by using the methods stated above)

I used to use the 25mm and then the 25mm and a celestron 2x barlow to pull out the detail before I upgraded to an 8mm bst starguider.

Lastly, make sure your in focus, if the targets blurry play with the focuser.

Hope this helps.

[AstroMuni]

44 minutes ago, ashish83 said:

So would you recommend to use 2x Barlow with 25mm eyepiece to get better view?

Like I mentioned earlier this combination will get you a magnification between the 25mm and the 10mm. So if you already have a barlow, just go for it!

In this hobby, you will hear different people giving you difffering views of what they can or cannot see. But as we are all built different, just give it a shot and enjoy the view is my motto.

If you have the budget, go out and buy the best EPs you can get for the money. There is plenty of discussion available on this forum to assist you 🙂

[happy-kat]

Welcome

The heritage 130p with supplied 10mm eyepiece will show that Saturn has a ring and will show Jupiter's main bands and 4 main moons. x65 magnification

I have seen a moon shadow on Jupiter with this telescope and my own 6mm eyepiece though I cannot recall if I also used a 1.6x barlow I have .

The planets are low in the sky right now and you were inside through class adding heat thermals, glass and low level atmospheric muck so very challenging for clarity on the planets right now. So you get a feel on focus try looking at the Moon, it's lovely.

Edited July 24, 2020 by happy-kat

[Chris]

Go out side for starters, focus on a bright star. I suggest Polaris as it wont move. Get it in the centre if the eyepiece then de focus it until it looks like a dougnut shape. If the doughnut shape is symmetrical then your scope is collimated. 

The 10mm eye piece that comes with these scope (the Super 10) is a very crude modified achromat design and it's gives a soft image. The 25mm is ok though. You may want to upgrade to something like a cheap 15mm Plossl eyepiece and a 2x Barlow lens. This will then give you a range of magnifications 25mm 15mm, 12.5mm, and 7.5mm. At 7.5mm you'll be at around 87x mag which will get you a little closer to the action and you'll be able to see the rings of Saturn a bit easier plus the cloud belts of Jupiter. You could probably get a 12mm and Barlow for even higher planetary views only the eye relief starts to get tight with Plossls around 10-12mm

First of all test go outside, let the scope cool, and test collimation plus the supplied eyepieces. Have fun  

[ashish83]

Yes, I will certainly look up Moon once it comes out of its New Moon phase. Next time I am going to go out to try this scope. The only issue is I need to find a place from where I can see the planets as my garden faces north-north east

@Lockie, Thanks for the advise on collimation, I will give it a go.

[AstroMuni]

12 minutes ago, ashish83 said:

my garden faces north-north east

You might be able to see Andromeda galaxy M31.

12 minutes ago, ashish83 said:

Thanks for the advise on collimation, I will give it a go

Read this https://garyseronik.com/a-beginners-guide-to-collimation/

 

Edited July 24, 2020 by AstroMuni

[happy-kat]

Stellarium is a great planetarium program to see what is up where you are

[AstroMuni]

3 hours ago, Lockie said:

Go out side for starters, focus on a bright star. I suggest Polaris as it wont move. Get it in the centre if the eyepiece then de focus it until it looks like a dougnut shape. If the doughnut shape is symmetrical then your scope is collimated. 

Just to be clear about the term collimation, this would only show that the secondary mirror is aligned. Its a good place to start and can be done during daylight using a collimation cap.

To get proper collimation you would need to use a high magnification (the guide is around 25x per inch of aperture) so with a 130 (5 inch) you would need around 125x. Then you need to slightly defocus to get airy disk patterns. At low magnification you will not see these.

[Chris]

2 minutes ago, AstroMuni said:

Just to be clear about the term collimation, this would only show that the secondary mirror is aligned. Its a good place to start and can be done during daylight using a collimation cap.

To get proper collimation you would need to use a high magnification (the guide is around 25x per inch of aperture) so with a 130 (5 inch) you would need around 125x. Then you need to slightly defocus to get airy disk patterns. At low magnification you will not see these.

Yes always do it at high power with the star centred in the eyepiece to rule out eyepiece aberrations, that's correct. 

[Chris]

22 minutes ago, Lockie said:

Just to be clear about the term collimation, this would only show that the secondary mirror is aligned

 The way I understand it is if you adjust one of the primary mirror adjustment bolts significantly it will pinch one side of the doughnut as the primary moves out of collimation. The pinching is created when the Fresnel rings get pinched rather than the middle of the doughnut moving. Any asymmetry is down to this pinching, you just need to make sure you don't go wild and defocus a ton half filling the eyepiece as this dilutes errors in collimation so you can't notice them, you just see the secondary and a large fuzzy disc. It may be that we are talking about the same thing? 

With this in mind I want to make it clear to the OP that I mean defocus a star until it appears as a small doughnut, not a big one  

 

Edited July 24, 2020 by Lockie

[Timdog]

You will notice a big improvement if you are able to justify spending a bit on eyepieces once you have used the telescope. I have the heritage 130 and upgraded to the highly recommended bst starguiders, they are less than 50 each new and often come up second hand on here or on uk astrobuysell.  As a start possibly the 8 mm for higher power and the 18 for wider views. I found them to be a big improvement. Last night with the 18 and 12 I had good views of Saturn and Jupiter, the view with the 8 and 5 wasn’t as sharp, presumably due to the low position of the planets.

It’s a good telescope, very well regarded.  The other issue you can suffer from is stray light entering the tube if you are in an area with street lights etc. It may be worth looking at posts on here/YouTube on making a cheap simple light shroud for it.

Edited July 24, 2020 by Timdog

[Nyctimene]

Hello, and welcome, ashish83, to this friendly forum!

You have chosen a very capable and versatile telescope - I'm very pleased with mine; it's for good reasons my most used grab-and-go scope. The optics are excellent and will show you a lot of detail on planets and the moon, already with the stock eyepieces. A decent barlow will be useful to get higher magnifications; I'm using this one (small, lightweight and sharp):

https://www.teleskop-express.de/shop/product_info.php/info/p5503_Baader-1-25--Q-Turret-Barlow-and-photo-converter---2-25x-und-1-3x.html

You'll find a lot of information here (a huge thread!); the AWB One Sky Newtonian is just the US brand of the 130 P Flextube:

https://www.cloudynights.com/topic/463109-onesky-newtonian-astronomers-without-borders/

Take yourself time, enjoy each step of learning; start an astro diary, and have fun!

Stephan

[ashish83]

Hi All,

Thanks for your replies. @Lockie and @AstroMuni , thanks for your advise on collimation.

I got a brief opportunity to take the telescope out over the weekend. I left if outside for couple of hours and then tried to focus on Jupiter. But all I could see is very bright white light  I got beautiful views of moon though. Also I could make out the rings on Saturn with 10mm eyepiece but no other details. With 25mm eyepiece I could not make out any details on Saturn as well and it was just looking as a very bright star in the scope. The weather seems to be bad for this week as well so won't get the chance to test the scope much this week.

[AstroMuni]

1 hour ago, ashish83 said:

Hi All,

Thanks for your replies. @Lockie and @AstroMuni , thanks for your advise on collimation.

I got a brief opportunity to take the telescope out over the weekend. I left if outside for couple of hours and then tried to focus on Jupiter. But all I could see is very bright white light  I got beautiful views of moon though. Also I could make out the rings on Saturn with 10mm eyepiece but no other details. With 25mm eyepiece I could not make out any details on Saturn as well and it was just looking as a very bright star in the scope. The weather seems to be bad for this week as well so won't get the chance to test the scope much this week.

This suggests that your viewing conditions are poor (probably due to light pollution). Using the 25mm you should atleast be able to see an oblong star and the moons of Jupiter. But good to hear that you saw beautiful views of the moon 🙂

[ashish83]

Yes Jupiter is just above a street light from my view  Will a light shroud help with this situation or do I need to find a different place to setup the telescope?

[Starwatcher2001]

I'd set up in a different place to see Jupiter, or wait until it's moved.  I know at the moment that's not aways easy with it being so low. I've got around a 40 minute window when it's visible between my house and the next. If I move the scope into the front garden I'm swamped with light.

[AstroMuni]

22 hours ago, ashish83 said:

Yes Jupiter is just above a street light from my view  Will a light shroud help with this situation or do I need to find a different place to setup the telescope?

 Dont think a light shroud would greatly enhance your view especially if street light is directly ahead. A light pollution filter may help (see https://astrobackyard.com/light-pollution-filters/) but a simpler way is to find a better spot for your scope.