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First view of Jupiter, advice for next viewing


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Hi All,

Well it is now 3am, I have just got back in from the garden after viewing Jupiter for the first time!

My scope and bits are in my signature and I rushed at tonight's viewing due to a bit of cloud cover and being impatient (I know I shouldn't) but I was rather satisfied with my viewing tonight but looking for a little advice for future.

I do not currently have any vibration pads so that may be the reason but I did notice that after I had setup my view is very shaky if I am trying to focus the eyepiece, I started with the 25mm after doing a solar system align to the Moon, I centered Jupiter in the 25mm after moving to it. I then went straight to the 9mm and repeated and then got greedy and went for the 4mm.

I ended up using my 6mm eyepiece and that gave me the best view after a bit of focusing. I do not know if it is just me or the scope in general but I found that when trying to focus the view got massively shaky to the point Jupiter was jumping in and out of the FOV of the eyepiece. I have got a thumb screw that will lock the focus-er but until I have the right focus I have this unlocked and the shaking is very irritating when trying to center and focus the view.

Again I do not know if it is just me but I have noticed if I put the focus all the way in and then slowly turn the focus the whole unit (Cant think how to describe it) kind of lifts upwards a bit before rolling out thus disrupting my original position. (I am most likely making no sense at all now) I have packed my scope away now but if that makes no sense to you I can make a video tomorrow. Basically is this normal? Or is there a fault with my focus unit when moving up and down the rail.

What would you recommend for best viewing Jupiter? Was I right to stick with the 6mm? It would be nice to get a closer look so would a Barlow be a good option? 

Lastly, how does everyone store their scopes? I put my optics tube back in the box it came in with the polystyrene support, all my eyepieces and bits all get packed back into there original packaging then all stored in a box, and the tripod gets folded up and leans in the corner of my room with the optics box on end with it.

Thanks for any advice!

---------------------------------------------------

Celestron NexStar SLT 130 (Celestron 25mm and9mm included)-  4mm Skywatcher eyepiece - 6mm Skywatcher eyepiece - Skywatcher 4 filter set (Moon & Planets) - Skywatcher 7ah Power Tank - Celestron heavy duty power lead - Light pollution filter
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Hi, I've never used your scope but after reading some reviews the main complaints seem to be the focuser and the mount as you were describing. Some people have put sand in the legs of their tripod to make it heavier or hung weights from the underneath of it, but obviously make sure you don't damage your mount by doing this.

Depending on how much you want to spend, you could replace the focuser with a suitable alternative that fits the mount. As for as viewing Jupiter goes it depends on seeing conditions at the time. I generally find it in my lower mag eyepiece and then push the magnification up until I get the image scale I want while losing as little detail as possible.

You're best off waiting for any target to be high in the sky to get the best views as this cuts down on atmospheric disturbance. There's some good tips on planetary viewing on this vid:

https://www.youtube.com/watch?v=bM9g18Q109o&list=UUIwQ5bWXAf57sE5HN6ldW3Q

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I too haven't used your scope but just looking at the pictures it does look to have a very lightweight mount/tripod with spindly legs. Unfortunately with this, and other such scopes, the majority of your cash goes on the electronics.

However that's not what you want to hear and there are a number of things you can do to make it more stable, like suppression pads. Also try to keep the legs extended as less you can, the longer the legs the more shaky it will become. Also extra weight on the tripod, I'm not sure about loose swinging weights underneath, I would go for a heavy weight added to the accessory tray/leg spreader.

As for the focusser I've heard people use a peg on the adjustment wheel to make the turns more accurate and less shaky.

I have a scope with the same specs 130mm x 650mm and find the highest useful magnification is with a 4mm EP. I don't know what kind of eyepiece your 4mm is, mine is a mid range UWA. I have barlowed a 6mm plossl but the view wasn't that good, you would need exceptional seeing condition to use it.

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Hi and welcome to SGL

I had the Skywatcher version the 130 az goto syncan, at high magnification you are going to notice any vibration whilst focusing, a possible solution maybe a dual speed focuser such as a Crayford focuser this may help. also is the vibration coming from there being a little bit of slop as i would call it from the focuser itself have a look underneath the focuser. Next to the locking screw there should be a Allen screw see if you can adjust this to take any slop out I am inclined to think this is the problem after reading your post a couple of times

.

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Hi  LFFPicard,

IMO, Jupiter requires 150-200x what in you scope translates into 4.3-3.3mm. So, I guess your 4mm eyepiece should be fine under good seeing conditions since it gives ~160x. I suspect you can reach 170-190x on your scope under excellent seeing conditions so something up to 3.5mm would be OK.

But everything depends on:

1) collimation

2) thermal equilibrium

3) atmospheric conditions

4) object elevation

It's important for high power planetary observations to get your reflector scope well collimated. But if the view through your 6mm eyepiece was fine, than I'd assume everything was OK with the collimation.

For best sharp planetary views your reflector scope primary mirror should reach ambient temperature. For that, you have to pull your scope outside at least 1 hour or so before observation to cool it down.

If you did all these properly than a turbulent atmosphere is the next suspect of the blurry high power images. In your situation, most probably, poor seeing was responsible for suboptimal views through the 4mm eyepiece. The turbulent atmosphere used to limit the max possible magnification for  sharp Jupiter views, so you have to go down until reaching the magnification providing the best view what you actually experienced. You need to plan your observations carefully and check the sky quality in advance. If you look at night sky and see the stars are twinkling with high frequency it's unlikely to be a good night for planetary observations. But there are some better ways to estimate the seeing conditions, e.g. by pointing your scope to any bright star and estimate stability of the view at the Pickering Scale . I usually don't observe planets when seeing is poorer than 6 at the Pickering Scale. You may want to check out also these useful sources ( link1 , link2 ). And you can plan you planetary observing sessions by checking astro forecast  websites like Meteoblue.com (go to Air > Astronomy Seeing).

Also don't forget one more important thing, Jupiter (like any other object) elevation should be higher than 30* for best view.  And the very best view possible when it's just above you head, that is at 90*.

What else could be good for Jupiter is any contrast enhancing filter. I use the Baader Moon & Sky Glow. Although, if you have any other color planetary filters you can use them. But the Baader M&SG is the best, IMO.

I can't suggest anything on fixing your focuser since I'm not familiar with your scope. But if you'll find that your tripod is shaking, you can, for example attach (hang) some load like 10lb dumbbell  or so to stabilize it.

As for the scope storage, you can keep it on tripod with OTA lid closed. To better protect from dust, also cover both ends of the OTA with plastic shower caps. And just keep the whole thing covered, I use large 33 gal black garbage bags.

And always keep the OTA dry, avoiding fogging the primary mirror. If you need to bring your scope from outside when it's cold, than put OTA in a bag (e.g. plastic trash bag), close it carefully and remove OTA only after it has been warmed up.

Hope that helps.

Cheers

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Think the mount is simply too lightweight and so the thing will shake. Unfortunately manufacturers tend to put the scope on the least expensive they can get away with and yours is 130mm and 650mm focal length. So a reasonable sized scope, it would have been better on an EQ3-2 mount however I have the idea they do not offer it on that mount.

Also the higher the magnification the greater the shaking appears, both get magnified.

I do not know if the EQ2 head will go on to an EQ3-2 tripod - if anone knows they may say.

Also not sure if a better dovetail would help, it may enable things to be held better.

The focuser problem is simply again an inexpensive focuser, but a 2 speed one costs money..

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Hi All,

Well it is now 3am, I have just got back in from the garden after viewing Jupiter for the first time!

My scope and bits are in my signature and I rushed at tonight's viewing due to a bit of cloud cover and being impatient (I know I shouldn't) but I was rather satisfied with my viewing tonight but looking for a little advice for future.

I do not currently have any vibration pads so that may be the reason but I did notice that after I had setup my view is very shaky if I am trying to focus the eyepiece, I started with the 25mm after doing a solar system align to the Moon, I centered Jupiter in the 25mm after moving to it. I then went straight to the 9mm and repeated and then got greedy and went for the 4mm.

I ended up using my 6mm eyepiece and that gave me the best view after a bit of focusing. I do not know if it is just me or the scope in general but I found that when trying to focus the view got massively shaky to the point Jupiter was jumping in and out of the FOV of the eyepiece. I have got a thumb screw that will lock the focus-er but until I have the right focus I have this unlocked and the shaking is very irritating when trying to center and focus the view.

Again I do not know if it is just me but I have noticed if I put the focus all the way in and then slowly turn the focus the whole unit (Cant think how to describe it) kind of lifts upwards a bit before rolling out thus disrupting my original position. (I am most likely making no sense at all now) I have packed my scope away now but if that makes no sense to you I can make a video tomorrow. Basically is this normal? Or is there a fault with my focus unit when moving up and down the rail.

What would you recommend for best viewing Jupiter? Was I right to stick with the 6mm? It would be nice to get a closer look so would a Barlow be a good option? 

Lastly, how does everyone store their scopes? I put my optics tube back in the box it came in with the polystyrene support, all my eyepieces and bits all get packed back into there original packaging then all stored in a box, and the tripod gets folded up and leans in the corner of my room with the optics box on end with it.

Thanks for any advice!

---------------------------------------------------

Celestron NexStar SLT 130 (Celestron 25mm and9mm included)-  4mm Skywatcher eyepiece - 6mm Skywatcher eyepiece - Skywatcher 4 filter set (Moon & Planets) - Skywatcher 7ah Power Tank - Celestron heavy duty power lead - Light pollution filter

Hi there,

The 6mm ep is the right f/length for Jupiter in my opinion, giving about 106x, however, Jupiter will take up to 150x, so a Barlow would be too much.  But you don't always benefit from maximum magnification so your current configuration sounds optimum.

On the question of storage, I always leave my telescopes up, so that any condensation can run off or dry, same for ep's, don't store them away until the next day is my advice.

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An 5" f/5 is not an ideal planetary scope. Being of such a short focal length it relies on very short focal length (FL) eyepieces to gain significant magnification. A longer FL telescope allows one to use longer FL eyepieces, which in turn would give one more eye relief making viewing a more comfortable possibility.

As you'll appreciate, magnification is equal to the telescope's FL divided by the EP's FL. So, if I wanted to enjoy Jupiter, for example, at around an average night's viewing of 140x to 160x in the 5" f/5, I'd need an eyepiece of around 4mm to 4.5mm. I often view Saturn between 150x to 200x, so if this were the same for you, we'd need FL EP's around 4mm to 3.3mm.

If you were wanting to do planetary observations, typical recommendations for a 5" f/5 might include: i) a zoom eyepiece of decent quality of between 3-6mm ii) a decent Barlow which in effect helps double your EP collection whilst giving you the choice of buying a little longer FL eyepiece (say an 8mm giving you a hand in viewing DSOs and lunar work) and retaining its longer eye relief; iii) a 60º field EP of around 4mm which due to its wider field will be easier to track your object.

Although I have never used you scope, I feel it will be a well crafted wide-field scope and these rich field scopes can look at planets all the time. I really enjoy watching Jupiter in my little 76, for example, but whatever our telescope, I think it is always helpful to have reasonable expectations of what is realistically possible.

If the mount is shaking check the bolts at the top of the tripod. If they are loose or not fully tightened the mount will be a little unstable. Other than that, if it continues to wobble you'll probably either need to reduce power so you're not tracking and focussing so much, or get a more reliable mount. For myself, I have never been particularly happy with mount wobble and maybe an upgrade in this direction would make a significant improvement.

However, In the long run, rather than investing in more eyepieces, or a new focuser, mount, tripod etc to deal with high power planetary work for your scope, it might be an idea just to look out for a cheap longer focal length telescope and build around that. It's an idea, nothing more :grin: .

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I think we share the same mount, but anyways try this;

1. Put some weight on the accessory tray, I use 5kg and then check the legs are spread out (this may sound obvious but sometimes the legs might not be fully spread wide even though you think they are)

2. Put a clothes peg on the focusser, this makes sooo much difference.

I use mostly use 188x for Jupiter depending on conditions so as already stated you mag is about right. Btw is your 9mm the stock Celestron one ? If it is the same as the one that came with my scope then it is pants, I recommend you replace as some point with eg a BST 8mm.

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I had same issue with EQ5 and SW-200

you could look into something like this ( worked for me , focusing is so much easier with it )

http://www.teleskop-express.de/shop/product_info.php/info/p6385_Skywatcher-AccuFocus-for-Dual-Speed-Crayford-Focuser.html

just make sure it fits your focuser

Yeah, if you have this focusser, I can recommend the autofocusser (although it's actually a remote control, it isn't automatic).

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