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Hello All,

Total newcomer to Astronomy here, although I have always been interested/fascinated - I have only recently taken to leap with a 2nd hand Sky Watcher 150P.

I love it, I've been out, seen the moon a few times, taken photos, looked at some star clusters and gradually learning the night skies through reading TL@Orion and mainly blog posts here.

BUT! and I'm almost sure this is me - but I will ask anyway.

First Issue: I can get extremely clear images of the moon using the supplied 10mm & 25mm lenses, but when i try the same any of the planets - all I see is bright objects. from the blogs i have read I have set my expectations - 6" reflector should give me something like a pea sized image of Saturn right? but I don't get it. Am I doing something wrong? I set up polar alignment, use star charts etc, so I am almost confident that I am looking at the right objects, but cannot see the detail.

Second Issue: the eye piece came with some sort of extension, not sure what it is but it fits into the focus tube and extends the tube - when i try using this it just blurs all the images. even the moon. what is this for & am I using it correctly.

Hopefully some of this makes sense - do I need a better lenses, am I using them incorrectly!

Thanks

 :)

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Go a little higher than 6" if you can afford too.

Welcome to SGL.

The Moon will look fine due to its size, brightness and distance from Earth. As the planets are further away, there lies the problem?

I had a similar experience with my 5" 127 EQ small image with the Planets, but the Moon was fine.

The jump to a larger telescope was key to my progression. The larger the mirror the more light that can be gathered and more detail obtained. Then using whatever choice of eyepiece you desire will allow you to see the image, magnified at the focal plane.

Good collimation is essential as are the seeing conditions. My images ofJupiter are superior than that offered from the 5" telescope, but could be bettered further in detail from an even larger telescope, more light, greater detail.

Does that extension have a lens in it? Its possibly a Barlow extension. If its a 2x then it effectively doubles the magnification of any eyepiece you insert into it. If this is the case, then your at the extremes of what the telescope is capable of, and the seeing conditions need to be perfect at the higher magnigications.

Edited by Charic

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The extension is either an adaptor for 2" diameter eyepieces, or a camera adaptor for attaching imaging equipment. Either way if you use them with your 1.25" eyepieces it will alter your focus and blur everything.

When you switch from the moon to a planet the focus needs to be altered. As Charic says, planets are further away - so you need to find the focus point by turning the focus knob slowly one way or other until everything gets sharp. Saturn will be very small with the 10mm eyepiece in that scope, but you will be able to see the rings and planet clearly and maybe even distinguish the cassini division between the rings. Jupiter will be a tiny bit larger and the banding will be easily discernable. But you always need to focus the scope.

Make sure the focus tube is moving in/out by checking the little thumbnail screw underneath the focuser isn't too tight. It needs to be just tight enough to hold the tube and eyepiece firmly in place, but slack enough so the tube actually moves smoothly in/out. Hth :)

Edited by brantuk

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Hello All,

Total newcomer to Astronomy here, although I have always been interested/fascinated - I have only recently taken to leap with a 2nd hand Sky Watcher 150P.

I love it, I've been out, seen the moon a few times, taken photos, looked at some star clusters and gradually learning the night skies through reading TL@Orion and mainly blog posts here.

BUT! and I'm almost sure this is me - but I will ask anyway.

First Issue: I can get extremely clear images of the moon using the supplied 10mm & 25mm lenses, but when i try the same any of the planets - all I see is bright objects. from the blogs i have read I have set my expectations - 6" reflector should give me something like a pea sized image of Saturn right? but I don't get it. Am I doing something wrong? I set up polar alignment, use star charts etc, so I am almost confident that I am looking at the right objects, but cannot see the detail.

Second Issue: the eye piece came with some sort of extension, not sure what it is but it fits into the focus tube and extends the tube - when i try using this it just blurs all the images. even the moon. what is this for & am I using it correctly.

Hopefully some of this makes sense - do I need a better lenses, am I using them incorrectly!

Thanks

  :)

Thanks Charic, Unfortunately If i invest any more at the moment, I will be living alone  :huh:  she is still to find her love for astronomy... one day.

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Thansk brantuk, I have thought that it might be an adapter of some sort. I will leave it at home from now on.

In relation to focusing, I don't think that is the issue. I can adjust the focus to get a nice sharp image for example, on the moons surface I can focus in and out,, getting very good detail of the surface, but cannot get the detail that you describe when i try the same focusing on planet objects. Ive tried all the variations with the 10mm with & without barlow, and 25mm same. very clear image of a bright object which is just bright and shiny but no discernible features.. !!

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Thanks Charic, Unfortunately If i invest any more at the moment, I will be living alone  :huh:  she is still to find her love for astronomy... one day.

I'm sure she loves you more, but an interesting test.

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You may need to collimate the scope, do you have the collimator to do this.......

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A 150P is f/5 so 650mm focal length, with the 10mm you will be getting 65x, and that would be reasonable for Jupiter but likely a bit too little for Saturn.

There is in effect nothing to see "on" Venus, it is cloud covered so all you see is the top of the assorted cloud layers, no detail.

Add in that Saturn is low down and the atmosphere has a habit of spoiling things, shame that we need it to breathe but you cannot have it all.

To see Saturn you will likely need around 100x and above. Meaning a 7mm or 6mm eyepiece will be required.

One other thing is how far away is your proverbial pea? Every planet comes out small.

Saturn is also a "strange shape", the disk that we go to look at is at an angle and so what you see is a not a nice round planet.

The 150P will do a good job, it is a nice scope to get started with and a convenient size.

You may need to check collimation as best you can, if that is out by sufficent then the image quality suffers.

Not sure where in London but monthly there is a meet at Regents Park, may be worth getting along and seeing people. People are a good source of information.

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A six inch reflector should give perfectly good views of the planets when all is well with it. However, the focal length is 750mm which means, that with a 10mm eyepiece, you'd need a 2x Barlow to reach 150x - which is a sensible magnification for starting off with the planets. 75x, which is what you get with the 10mm on its own, is insifficient magnification for planets.

Instead of a Barlow you could try a 5mm eyepiece.

Olly

PS Just crossed with Ronin but I prefer my result for 5x150 to his!  :grin:  :grin:  :grin: That apart we are saying much the same thing.

Edited by ollypenrice

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As Olly has said a 6" scope is more than capable of delivering great results on planets. The problem with planets is often the seeing specially in London as the buildings etc cause all sorts of thermals that mess with any planet low in the sky. 

I really don't think aperture is your problem. :) 

Check your collimation and keep observing it will come. 

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Charic, Funnily enough - She just said  "perhaps in the future"... who knows what the future will bring..

Thanks for the advice everyone, I had planned to go to Regents Park shortly - Baker St Irregulars group - so perhaps a bit of hands on with an expert will show be my flaws.

I'll keep my eye out for a 5mm too.

Cheers :grin:

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I'll be visiting London in July. Maybe check out the parks myself and Widescreen? Does the Planetarium still produce Laser Concerts or did they stop back in the early eighties?

Sadly, No, having just checked. Full of dummies?

Edited by Charic

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Ronin and swamp thing have it nailed I think.

The seeing in London really is a big factor ( no idea if it's the same in the suburbs but who'd want to live there, lol! .......easy there, suburbanites - just a wee joke!)

I've found with my 6"/F5 that things really start clearing out from about midnight as the ground/building heat begins to dissipate. But observations are still possible and rewarding earlier - if the sky is not obscured, it's always worth trying the scope.

With your 6" (and as you improve your eyepieces from stock) you will be able to see banding on Jupiter and the Great Red Spot, and Saturn's rings and at times the Cassini Division ( rare but...) and some banding on the disc itself. The planets will always be smaller than you'd like them to be, but no less wonderful for that. Give it time: there are some nights where nothing comes easy - and then there are others that will take your socks to the laundry. Sadly, in London the former tend to be in the majority but that's all part of the fun...and makes those fewer clear nights memorable.

ps Should you live near East London, always happy to meet up and compare notes, stuff etc. The Baker St group looks wonderful too - I really must drag my sorry self to one of their meets.

Edited by ghostdance
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Hello,

I'm a beginner too, but I have a similar scope.

An x2 barlow is standard equipment with the Skywatcher 150s (I have a 150PL) so if there's a lens in that tube that defocuses everything it''s probably a barlow and if so your problem is simply that you have to wind the focuser quite along way to get back in focus with it.

My 150Pl is almost twice the focal length of yours (1200 instead of 700) and even with that planets are exactly what I'd call pea-sized although Jupiter's bands, red spot, moons and sometimes the shadows of moons on the planets are visible. remember Jupiter is past conjunction now and nowhere near as big as it was a few months ago. Saturn is near its max size, but if you ignore the rings its less than half the size of Jupiter.

I have the same 25 and 10mm eyepieces which give me 96x and 240-x magnification. In theory my scope would be happy with an 8mm EP and the barlow to give about 300x magnification. I have a cheap 6mm eyepiece and it's just about usable but I think the poor quality harms the view more than pushing the magnification a bit too far.

Your magnifications will be just 28 and 70 which are good for looking at stars and clusters but not planets! If you haven't got a reasonable x2 barlow get one or even an x3. Getting a 4 or 5mm EP with the x2 barlow on your scope would give you about 300x magnification which is fine for a 150mm scope.

You may actually be suffering from over-bright images with that much aperture and low magnification. Even on my scope I find that the images of both Jupiter and Saturn can be too bright for my eyes when they are dark-adapted!

Long and short of it, I am much less experienced than these guys, but I suspect you are just short of magnification for planets with the standard setup but I think you can squeeze more magnification out of your scope.

Anyway, it's all good fun.

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Cool thanks Stub Mandrel. its good to know others have had some experiences like mine and have figured them out. I supposed doing all of this is part of the fun of it.

Cheers. Now for the clouds to part...

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Yup - my old 150P was 750mm focal length. And I agree with Olly - the 10mm barlowed will do it for Saturn. Otherwise the problem will either be seeing conditions or collimation of the scope. You'll get some great hands on experience with the Baker St Irregulars and Simon form Widescreen. Good luck with them and let us know how you get on. :)

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Ronin and swamp thing have it nailed I think.

The seeing in London really is a big factor ( no idea if it's the same in the suburbs but who'd want to live there, lol! .......easy there, suburbanites - just a wee joke!)

I've found with my 6"/F5 that things really start clearing out from about midnight as the ground/building heat begins to dissipate. But observations are still possible and rewarding earlier - if the sky is not obscured, it's always worth trying the scope.

With your 6" (and as you improve your eyepieces from stock) you will be able to see banding on Jupiter and the Great Red Spot, and Saturn's rings and at times the Cassini Division ( rare but...) and some banding on the disc itself. The planets will always be smaller than you'd like them to be, but no less wonderful for that. Give it time: there are some nights where nothing comes easy - and then there are others that will take your socks to the laundry. Sadly, in London the former tend to be in the majority but that's all part of the fun...and makes those fewer clear nights memorable.

ps Should you live near East London, always happy to meet up and compare notes, stuff etc. The Baker St group looks wonderful too - I really must drag my sorry self to one of their meets.

If I had to make a guess as to why he isn't seeing much of jupiter right now, it would be because it's much further away than it was a few months ago. I'll have to give it another go with my bins (I know that I was just able to make out the moons before, should see if I still can)

but it's cloudy all night :(

Stellarium says that jupiter is 32.6 arc seconds across today, but would have been 45 in February.

But, my 5" f/6.9 scope at 36x could still make out some equatorial bands, but never the GRS (it's never out when I am!) with little to no gain (aside from size) when viewing at 90 or 72 (25mm with barlow). Perhaps OP has some atmospheric turbulence blurring it all out, or perhaps he's not looking hard enough ;)

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Heh...atmospheric turbulence is a common occurrence here Pip :)

Interesting point about the distance - haven't factored that in apart from knowing when planets are at opposition or whatever-it's-called (scientific observer? Moi? Non!!!)

:)

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Crisis resolved. Was out last night and got some nice views of Saturn. it was not the lens, it was me... :tongue:  Although I think I may invest in some better EPs going forward.

Thanks erveryone for all your help.

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The moons are always visible to binoculars on anything resembling a clear night provided they are not in front of the planet or behind it.

Good to hear you're winning!

Olly

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