Author Topic: Expectations  (Read 1931 times)

John Edwards

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Expectations
« on: December 24, 2017, 02:46:13 AM »
Hello all,

I'm looking for someone who can either temper my expectations or inform me I'm doing something incorrect.  Here is my own story.

I have enjoyed laying under the stars at night for several years.  It is silent and curative.  I decided to get a little more serious in my stargazing and purchased a Celestron 130 SLT for Christmas.  It arrived with Celestron 9 mm and 25 millimeter eyepieces.  My goal was to start viewing easy things, such as the planets, together with my first targets being Venus, Mars, Jupiter, and Saturn.  I was quite excited at the possibility of viewing details of these plants, particularly the rings of Saturn.

So far, I have been very disappointed in my own ventures.  I have mainly used the 9 millimeter eyepiece in an effect to get as much detail as possible.  Mars has proven to be a red dot at the sky (no bigger than once I looked through binoculars).  Jupiter is a golden dot (although I will say it was pretty cool getting to see the dots which are Jupiter's moons).  If I seem just tough enough, I can BARELY see the rings of Saturn.

I figured that my problem was magnification, so that I did some studying.  I read about the benefits of a Barlow (i.e. improved magnification, economical way to double click the lenses you have, etc.).  I purchased a Televue Barlow 2x and was excited to use it.  I guessed double magnification would result in larger, clearer images of the planets.

 I was wrong.  In fact, I really cannot see any difference in the size of these planets (which also means I'm not seeing anything that I couldn't see just using the 9 millimeter eyepiece).

So, going back to the start of this article, I want your advice/thoughts on if I just have to temper my expectations (i.e. the little dots are the best I will do and to appreciate them for what they are) or when I'm doing something wrong which I should be fixing.  I appreciate any insight.

BvF13



Todd Treser

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Re: Expectations
« Reply #1 on: December 24, 2017, 09:22:09 AM »
You ought to be seeing more.  The rings of Saturn, for example ought to be easy.  Cloud belts on Jupiter, Mars is always tough.  But with the 9mm eyepiece alone, you'd get about 72x which would be enough for better detail.

I think something is not right with your setup, like collimation (alignment) or another issue.

Have you checked that the collimation?  Others who know the extent should weigh too.

Greg Quevedo

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Re: Expectations
« Reply #2 on: December 24, 2017, 03:48:50 PM »
Planets are finicky things, particularly when you're first starting out from the pastime.  Some nights that the "seeing" is just bad, which means unstable, blurry images from the eyepiece (whatever the magnification), and for a variety of reasonsplanets are especially sensitive to poor seeing.
Secondly, if you are viewing things close to the horizon (such as Mars until the next resistance, or like Jupiter early in the day until it climbs nicely into the skies) you are looking through a great deal of atmosphere that also leads to poor seeing.
Also, don't automatically assume that more magnification is greater.  You can have a nice, sharp, compact image at low cost, and allow it to be fuzzy and dim by putting too much magnification on it.  It's about using your judgement to find the best image at the eyepiece.  That judgement grows over time in this pastime, as you explore several kinds of targets (there's lots to see up there apart from planets).
Finally, as others have mentioned, ensure your range is collimated and in good shape for celebrating.
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trapoutampub

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Re: Expectations
« Reply #3 on: December 28, 2017, 06:50:20 PM »
Well, with 9mm eyepiece and 72X mag Saturn is not going to be very big.
You can put your scope/eyepiece info here and see.

redoroto

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Re: Expectations
« Reply #4 on: December 28, 2017, 08:58:09 PM »
Something wrong there with the simulator. I can see Saturn and rings easy with a 50x50 spotting scope. Not big, but very clear.

Dan Square

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Re: Expectations
« Reply #5 on: December 29, 2017, 02:02:38 PM »
Quote
Something wrong there with the simulator. I can see Saturn and rings easy with a 50x50 spotting scope. Not big, but very clear.
Agreed. Even in my 9x50 finderscope, I can see hints that Saturn is something other than perfectly round. At 50x the ring system is plainly evident.
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Jermaine Conner

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Re: Expectations
« Reply #6 on: December 30, 2017, 09:23:38 AM »
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Well, with 9mm eyepiece and 72X mag Saturn is not going to be very big.
You can put your scope/eyepiece info here and see.

All I see in the simulator is a small yellow dot.

praccelreber

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Re: Expectations
« Reply #7 on: January 04, 2018, 06:54:15 AM »
Quote
You should be seeing much more. The rings of Saturn, for example should be easy. Cloud belts on Jupiter, Mars is always tough. But with the 9mm eyepiece alone, you would get about 72x which would be enough for much better detail.

I think something is not right with your set-up, such as collimation (alignment) or some other issue.

Have you checked the collimation? Others who know the scope should weigh in also.

That is a good question.

Christopher Bryant

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Re: Expectations
« Reply #8 on: January 05, 2018, 04:09:29 PM »
Welcome to Cloudy Nights!

The mainissue is that a 130mm reflector with a 650mm focal length is not great at showing planets without some care. However, with a 9mm eyepiece and 2x Barlow you should be seeing more of Jupiter than you describe and that should be enough to give you a decent look if there is not another problem. Collimation, thermal equilibration, and not letting the planet get sufficiently high in the sky are the most likely problems.

Mars is very small now and will remain so for some time until it begins to approach the next opposition. We get a good look at it fora few months every two years. The rest of the time it is small.

Saturn is still very low in the sky unless you are catching it around sunrise. It will get better over the coming months. I haven't gotten a decent look at it so far this year as I have only seen it around 4AM when it is still quite low. That will change over the next few months.

The range you are covering between 9mm and 9mm plus 2x Barlow is large. The problemcouldbe that your scope might not be yielding good images at 144x right now, while 72x is still going to appear quite small. Something midway between (100 to 120x) could be helpful. Our eyes can trick us with respect to image scale. At the same magnification in two different scopes the larger scope's image can appear larger because it is brighter even if the actual image scale is identical.. Similarly if the image is already somewhat small and dim in a small scope increasing the power without getting more resolution (poor seeing, poor collimation, poor optics, etc.)can make it appear similarly small when in reality it is not. Why? Because it becomes dimmer and even less defined despite increasing the actual image scale.

144x is probably close to the effective limit for your scope. Splitting the difference (perhaps with a 12 or 13 mm eyepiece that can be 2x Barlowed with your existing Barlow) might help you find the sweet spot for your scope.

retpoiwerround

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Re: Expectations
« Reply #9 on: January 10, 2018, 06:39:46 AM »
It sounds like some of your problems might deal with collimation. To pull out the most details, the optics have to be aligned correctly. At present, I don't have any Newtonian reflectors, but my refractor is similar in focal length, but a touch smaller in diameter. I can easily resolve the rings of Saturn and see details in Jupiter. Mars has always been a tough one to get detail in (at least for me).

Another thing you might be dealing with is minor system vibrations and/or reaching critical focus. After touching the telescope to make focus adjustments, you will need to allow some time (usually between 5 to 30 seconds) for all of the vibrations to stop. The focal depth (the distance of perfect focus) on your telescope is about 2.5 thousandth's of an inch, the point being that it takes patience to adjust the focus to that precision.

My recommendations would be to be patient, learn how to collimate the telescope, and use it as much as you can. Experiment with different targets and methods of observing, see what works best for you.

Clear skies!

wetrerede

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Re: Expectations
« Reply #10 on: January 10, 2018, 07:31:13 AM »
I would bet it's down to poor collimation, not having the telescope cool down to thermal equilibrium, and looking at objects low in the sky.

All fixable!

Ryan Wilton

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Re: Expectations
« Reply #11 on: January 10, 2018, 12:29:42 PM »
Quote
Hello all,

I am in search of someone that can either temper my expectations or tell me that I am doing something wrong. Here is my story.

I have enjoyed laying under the stars at night for several years. It is quiet and therapeutic. I decided to get a little more serious in my stargazing and purchased a Celestron 130 SLT for Christmas. It came with Celestron 9 mm and 25 mm eyepieces. My goal was to start viewing simple things, like the planets, with my initial targets being Venus, Mars, Jupiter, and Saturn. I was very excited at the prospect of seeing details of the plants, especially the rings of Saturn.

To date, I have been very disappointed in my ventures. I have mainly used the 9 mm eyepiece in an effect to get as much detail as possible. Mars has turned out to be a reddish dot in the sky (no bigger than when I looked through binoculars). Jupiter is a gold dot (though I will say it was pretty cool getting to see the dots which are Jupiter's moons). If I look just hard enough, I can BARELY see the rings of Saturn.

I figured my problem was magnification, so I did some studying. I read about the benefits of a Barlow (i.e. increased magnification, economical way to double the lenses you have, etc.). I purchased a Televue Barlow 2x and was excited to use it. I figured double magnification would result in larger, clearer images of the planets.

Again, I was wrong. In fact, I really cannot see any discernible difference in the size of the planets (which also means I am not seeing anything that I couldn't see just with the 9 mm eyepiece).

So, going back to the beginning of this post, I need your advice/thoughts on whether I just need to temper my expectations (i.e. the little dots are the best I am going to do and to enjoy them for what they are) or if I am doing something wrong that I should be fixing. I appreciate any insight.

BvF13

You should be able to see at least two cloud bands on Jupiter using the 9mm eyepiece with your telescope.

Check the collimation and talk to the manufacturer if or once the collimation is OK. You can try focusing the telescope on the Moon and then point it at Jupiter without touching the focus.

Joe Mallard

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Re: Expectations
« Reply #12 on: January 10, 2018, 02:06:43 PM »
Quote
I would bet it's down to poor collimation, not having the telescope cool down to thermal equilibrium, and looking at objects low in the sky.

All fixable!


I looked at Jupiter a few months ago with the 20"at the dark site just before I packed up...it was just coming off the horizon and the seeing was typically bad for early winter, but I figured "why not?" I was sitting on the ground with scope pointedhorizontal. And all I could see of the planet itselfwas abigyellow orange ball with absolutely no bands showing. It was hopeless,probablythe least detailed look I havehad other than binoculars. I didn't want to wait an hour or two for it to get a little altitude so I packed for home.

Elroy Stockton

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Re: Expectations
« Reply #13 on: January 10, 2018, 05:23:20 PM »
It's a great question. I guess we all have had expectations of Hubble like images, yet really Mars (right now) is pretty much a small red dot in the sky.

But, then an interesting thing happens, we learn to observe with practice, observing preparation, collimating our scope, and observing on a good night when objects are well placed. Then, when well placed in in favorable conditions, we begin to improve the views we get because we learn what to look for and how to look for it.

So, our expectations might start too high, likely get dashed right away, then they recover a bit once we understand how and when to observe the things we want to see. It's a vicious cycle, but a rewarding one. We still do not get Hubble like views, but we get views we can appreciate. Learn and give it time.

colzefuli

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Re: Expectations
« Reply #14 on: January 10, 2018, 09:41:50 PM »
In my 7x50 binoculars, Jupiter appears as a disc and I can start to make out the shape of Saturn's rings. Are you sure the telescope is pointed at the planets? It sounds like you're looking at a star. Stars don't show changes in shape/size when you magnify them.