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Learning to use a telescope


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I’ve been using binoculars for more than a year to look at the stars. I thought I’d try a telescope so I bought a cheap one from Argos (Celestron Explorascope 114AZ Newtonian Reflector Telescope, Aperture 114mm, Focal Length 1000mm, Focal Ratio f/9, Star Pointer red dot finderscope. Original eyepieces replaced with 32mm and 9 mm Skywatcher Plossls.)

This was three months ago. I used the scope only for short sessions, because of poor viewing conditions. Then last night I had a long session because the skies were clear. I found the whole process very difficult.

The red dot finderscope seems only to work with bright stars. If I pointed it at a dimmer star, it disappeared once I had moved the finderscope to cover it. It seems that the light from the weaker stars is absorbed by the objective, so you can’t see it. You have to point the telescope where you think the star might be, and hope for the best. I tried finding Tejat and Propus in Gemini as a route to M35 (It’s in Turn Right at Orion). I could see them with the naked eye but they disappeared as soon as I turned the finderscope on them.

I did manage to identify Uranus using binoculars, it was a few degrees south of Mars, very faint and with a blue tinge. I focused the telescope on Mars, which was easy. It was harder moving the scope down to Uranus because there weren’t any other stars to guide me. When I did locate Uranus with a 32 mm eyepiece, focussing was difficult, the slightest touch on the focuser or scope made the image quiver and move out of focus. Minor movements of the eye made the image turn black and then reappear. Obviously some optical effect, possibly caused by wearing glasses. I think I tried to get a bigger image by changing to a 9mm eyepiece, but then couldn’t find the planet.

It seems to take lots of experience and skill to use a telescope effectively. What do forum members suggest I do?

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Despair not ! Last night (and with a little luck with clouds, tonight as well  ...) it was easy to locate: having had a good study of it last night I tried with the 10x50binoculars,and found it e

You are absolutely right - it does take lots of time to build up the skills and experience. You seem to be going about things the right way though so my suggestion is simply to keep at it. You wi

Hi Keora, Unfortunately,  many scopes are made down to a price and that usually means the mount provided tends to lack stability. I know what you mean about the limitations of the red dot finder.

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14 minutes ago, keora said:

...It seems to take lots of experience and skill to use a telescope effectively. What do forum members suggest I do?

 

You are absolutely right - it does take lots of time to build up the skills and experience.

You seem to be going about things the right way though so my suggestion is simply to keep at it. You will have ups and downs, successes and failures but that is the way of it I think.

Try and give yourself an "easy win"at the end of each session so that you end on a high note 😀

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Hi.  Another beginner here! 

I can totally relate to the frustrations of not being able to find things!  I have a red dot on my scope and I see the same thing - the target disappears when it's under the dot  - I guess because the dot itself is brighter than the target.  On mine, it's possible to dial down the red dot intensity, so that might be worth doing if you have a brightness control.  Have you aligned your red dot to a terrestrial target in daylight (like a distant chimney pot or whatever, avoiding looking at the sun!!!)?  If you do, at least you'll know that when the dot covers the target star, you're looking in the right direction.

Also, maybe start with something easy but nice at low power, as John says - I had some great views of M42 last night and that's pretty easy to find.

Pete

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I'm not sure but if you turn down the brightness a tad on the rds it may help, it's what I do sometimes for faint stars.  As John said keep at it and end on the session on a high take an image of the moon with your smartphone if you have one then it'll give you an image to edit an play with.  There are very few times that we in the UK can get out to observe so sometimes just go with the flow or research what object you'd like to observe in your next session and work the route to see it.  Keep going and clear skies :)

 

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44 minutes ago, keora said:

I did manage to identify Uranus using binoculars, it was a few degrees south of Mars, very faint and with a blue tinge.

You are one up on me !! Uranus and Neptune have eluded me so far. (Although i think uranus is  quite close to mars tonight ) . As for the RDF , i always favour a telrad .. it looks a bit industrial but i think its superior. I used to have a goto set up but i abandoned it in favour of tracking motors . The thrill of eventually finding your target is immense ... of course also a lot more difficult . Stick with it though . 

Edited by Stu1smartcookie
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Hi Keora,

Unfortunately,  many scopes are made down to a price and that usually means the mount provided tends to lack stability. I know what you mean about the limitations of the red dot finder. They can be frustrating when looking for more challenging targets. Still, on the bright side, you've been using binoculars for over a year which is a great way to start out and familiarise yourself with the night sky. Many observers use binoculars  on solid mounts at which point they become very serious tools, and are great fun too. The fact you found Uranus both in your binoculars and in your telescope tells me you're a good observer. Sometimes the image can black out when our eye moves off axis, but like all things worth doing, observing with a telescope is a skill and sometimes a challenge. From the little you've told us I'm certain you've got what it takes to become a very good observer. Perhaps it may help if you check all the nuts, bolts and screws on your mount to make sure they are not loose, and so minimise any unwanted movement. A 6X30 optical finder might also make a much more useful addition rather than the red dot finder. Other than that, just keep on observing and challenging yourself and your telescope.

 

 

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4 hours ago, keora said:

I’ve been using binoculars for more than a year to look at the stars. I thought I’d try a telescope so I bought a cheap one from Argos (Celestron Explorascope 114AZ Newtonian Reflector Telescope, Aperture 114mm, Focal Length 1000mm, Focal Ratio f/9, Star Pointer red dot finderscope. Original eyepieces replaced with 32mm and 9 mm Skywatcher Plossls.)

 

This was three months ago. I used the scope only for short sessions, because of poor viewing conditions. Then last night I had a long session because the skies were clear. I found the whole process very difficult.

 

The red dot finderscope seems only to work with bright stars. If I pointed it at a dimmer star, it disappeared once I had moved the finderscope to cover it. It seems that the light from the weaker stars is absorbed by the objective, so you can’t see it. You have to point the telescope where you think the star might be, and hope for the best. I tried finding Tejat and Propus in Gemini as a route to M35 (It’s in Turn Right at Orion). I could see them with the naked eye but they disappeared as soon as I turned the finderscope on them.

 

I did manage to identify Uranus using binoculars, it was a few degrees south of Mars, very faint and with a blue tinge. I focused the telescope on Mars, which was easy. It was harder moving the scope down to Uranus because there weren’t any other stars to guide me. When I did locate Uranus with a 32 mm eyepiece, focussing was difficult, the slightest touch on the focuser or scope made the image quiver and move out of focus. Minor movements of the eye made the image turn black and then reappear. Obviously some optical effect, possibly caused by wearing glasses. I think I tried to get a bigger image by changing to a 9mm eyepiece, but then couldn’t find the planet. 

 

It seems to take lots of experience and skill to use a telescope effectively. What do forum members suggest I do?

 

Yup I have a whole thread on RDF issues though mine is more related to light pollution and annoying angles :D I think my conclusion was to replace the RDF with a quikfinder and a 6x30 finderscope at some point! Still the issue you describe is exactly my experience with RDF, they are just to bright and it can wash out the stars, plus keeping both eyes open I find it difficult to integrate the dot and the background at times. Usually I use binoculars to hunt the area, then guess where to the put the RDF if there isn't an obvious star (or others to jump off from) and pan around with the telescope on my lowest magnification.

Well done on Uranus, I don't think I have ever managed to spot it though Mars is always quite nice but its hard to find / focus at higher magnifications. I suspect mine is down to a combination of the telescope chromatic aberration and telescope shake likely due to the aluminum mount. I'd suggest you go through and tighten everything up and maybe consider putting some extra weight hanging hang in the middle of the tripod (be careful not to endanger the tripod / telescope) which might help. Also I found if you can set it up and get the telescope ahead of where Mars is, then let it drift through the eyepeice so you don't get focus / altaz shakes at the same time as observing

Going to a higher magnification eyepeice will often have the opposite effect, you will get a dimmer image due to physics, I vaguely remember it is something like if you double the magnification the resultant image is four timers dimmer but I am sure others will know more :) 

Lots of experience certainly required but that is something that just comes with practice.

My only suggestion other than to keep browsing forums and reading is simply to plan out a ready to go session ahead of time which is something I am now trying to do to maximize telescope viewing time especially with the UK weather keeping me indoors mostly. I also keep a small book with my nights viewing, times, visibility, weather, targets, what was observed which is good to see how things are progressing etc. I have had my telescope since Nov and after a few unplanned sessions I am currently trying out seeing different types of objects to see what I like doing and how the telescope performs such as star clusters, constellations, nebula, galaxies and currently on double stars (I am hoping for a good moon session at some point and views of Saturn / Jupiter in the future) :) 

Edited by wibblefish
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Hello, Keora,

as John and Mike said above, you seem to be on the right track - finding Uranus with a telescope isn't an easy task for beginners; patience will bear fruits.

Many Red Dot Finders are way too bright, even at the lowest setting. But you can dim the red dot sufficiently by putting a tiny piece of old fashioned, developed 35 mm photographic film (think of an old surplus diapositive) across the exit of the red LED - works well for my RDF's.

You don't need to wear glasses when observing, if you are just short-or farsighted - you can correct this with the focuser. Only in the case of astigmatism you have to use the appropriate spectacles; usually no problem, when you upgrade to eyepieces with a long eye relief (> 15 mm); e.g the ES 62° LER. Hope this helps.

Stephan

 

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Thank you for all the encouraging comments. Here's me reply

Last night I had the red dot finder at maximum intensity. I never realised it would make it harder to see a dim star nearby. I'll turn it down for the next sighting.

I first set up the red dot finder using a red light on a telecoms tower 4 miles away as a target. I've checked the finder today by aiming at a tv aerial 50 yds away and it's fine.

I tried to look in the M42 area (Orion), unfortunately it was mostly concealed by some birches. It is a good area of the sky to look at, I'll have a go at a more suitable time.

I'd never heard of a telrad, I've just looked it up, It's worth considering if I get the hang of scopes and buy a better one. I've seen scopes with optical finders. I image they might be heavier and more expensive so they aren't included in beginner scopes.

The tripod for the scope seems quite sturdy, I'll see if I can hang a rucksack from the apex to weigh it down.

I have been keeping a diary of what I've seen and with a few sketches of the more interesting constellations.

I bought Skyr Safari a few months ago. It's on an iPad. It's very good for homing in on an area and using patterns of minor starts to confirm where you are.

Thanks again.

 

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1 hour ago, wibblefish said:

Well done on Uranus, I don't think I have ever managed to spot it though

Despair not !

Last night (and with a little luck with clouds, tonight as well  ...) it was easy to locate: having had a good study of it last night I tried with the 10x50binoculars,and found it easily , so came indoors and contacted friends who are interested in astronomy in a casual way,  I'd shared my scope with them on the clear night before the conjunction and enjoyed their delighted reaction to seeing Jupiter. rings, Saturn, / + moons, then Mars, the Pleiades and some double stars ,all for the first time in a telescope.  I know they have some good binoculars, and wondered if they would be able to see Uranus with them from their home in the centre of Leicester .

So, told them to locate the Moon, then look to the right by roughly the width of a closed fist and down a little ... that's Mars. Centre Mars in your binoculars ( probably about 6 degree FOV) and look for the grey-blue dot at about 7 o'clock , roughly half way to the edge of your view. Uranus !

An hour later I got an excited message back, not only had they found it in their binoculars despite the city light pollution, they had also uneartherd a 'toy'  Tasco refractor, stuck it out of a bedroom window and, against all conventional wisdom and odds, viewed a wobbly Mars & Uranus with it . How chuffed were they ?! Don;t give up, ,you can locate it !

Heather

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7 hours ago, keora said:

I’ve been using binoculars for more than a year to look at the stars. I thought I’d try a telescope so I bought a cheap one from Argos (Celestron Explorascope 114AZ Newtonian Reflector Telescope, Aperture 114mm, Focal Length 1000mm, Focal Ratio f/9, Star Pointer red dot finderscope. Original eyepieces replaced with 32mm and 9 mm Skywatcher Plossls.)

 

This was three months ago. I used the scope only for short sessions, because of poor viewing conditions. Then last night I had a long session because the skies were clear. I found the whole process very difficult.

 

The red dot finderscope seems only to work with bright stars. If I pointed it at a dimmer star, it disappeared once I had moved the finderscope to cover it. It seems that the light from the weaker stars is absorbed by the objective, so you can’t see it. You have to point the telescope where you think the star might be, and hope for the best. I tried finding Tejat and Propus in Gemini as a route to M35 (It’s in Turn Right at Orion). I could see them with the naked eye but they disappeared as soon as I turned the finderscope on them.

 

I did manage to identify Uranus using binoculars, it was a few degrees south of Mars, very faint and with a blue tinge. I focused the telescope on Mars, which was easy. It was harder moving the scope down to Uranus because there weren’t any other stars to guide me. When I did locate Uranus with a 32 mm eyepiece, focussing was difficult, the slightest touch on the focuser or scope made the image quiver and move out of focus. Minor movements of the eye made the image turn black and then reappear. Obviously some optical effect, possibly caused by wearing glasses. I think I tried to get a bigger image by changing to a 9mm eyepiece, but then couldn’t find the planet.

 

It seems to take lots of experience and skill to use a telescope effectively. What do forum members suggest I do?

 

You have run into some of the things the shiny telescope adverts fail to mention!

It's not just the telescope , the mount and tripod have a vital job to do keeping steady yet moving smoothly, not an easy thing to engineer at a low price point,

More magnification doesn't just mean things look bigger: it also means those wobbles will be magnified, and the less precise small movements of the mount will be annoying .Not only that, but the magnification that is possible is often further limited by the atmospheric conditions

To build a telescope package at a competitive low price point,  you often get accessories which are only just adequate. (bit the manufacturer will be very happy to sell you some upgrades )

And last of all ... just seeing things through a telescope (let alone finding things !) can take some practice ... hovering your eye in the right spot to not get the black outs you had for instance.

Persist, it's really worth it, honest. There are all sorts of add ons you can buy (lord knows I've splashed the cash on a few ...) but time spent, patience and persistence are free and never wasted . Yes, try weighting the tripod down, it should help. The stock RDF is a pain for faint objects, cheap optical finders can also be awkward to look through, which is why the more expensive ones which have right angled view are popular .

Absolutely worthwhile noting your observing triumphs frustrations and disasters , I've done so since starting off last summer,  and whilst I still feel like an incompetent dabbler, reading back I've at least got a tiny bit less incompetent ! You will make progress,  the learning curve is steep  at the start but it gets easier.

Heather

 

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I'm sort of a beginner too  I have returned after a long absence, but I have used quite a few scopes and used to be in charge of a stock.

I can give a few tips...

I'm surprised that you have to get the red dot of the finder right on the target in order to position the scope close enough to the target.  I'd have thought nearby was close enough.  But I used to have a similar problem though with an old refractor.  The viewfinder on that, as with my current scope, had quite coarse crosshairs as the sight mark.  Instead of calibrating the finder so that that the target was directly under the cross, I used to put it just off to (say) the top right so that it was still in view, but touching both lines.  If you are struggling with the red dot covering the target, how about calibrating so that the star sits just on top of the dot for correct position?  

About hanging things from the tripod to give a bit of stabilising weight.  Some of the team I worked with had to take a load of research equipment to China, they had an issue with counter balance weights for some of the apparatus, as they would have taken up an inordinate amount of luggage allowance!  The solution i suggested was to leave the weights at home and use bottled water when they got there, and empty these to adjust to the right weight.   Similarly, reusing a 4 pint plastic milk bottle will give you a convenient weight, it's even got a nice handle to hang it by.

As for easy targets for a finish.  Save the moon for last.  I find i can hardly see to pack away after looking at that, let alone be dark adapted to look at stars.

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Thank you for the extra advice.

When I look at stars, I normally try and position the red dot in the finderscope so that it covers the star I want.  This is because when I then look at the star through the scope, I'm not always sure I've got the right one. sure it's the one I want. All stars look the same when you're a beginner. I think I'll be more flexible - if I look at a dim star, I'll sight the red dot finder so the top of the finder is just below the star, then I'll push the scope a little bit further up and hope the star appears in the eyepiece.

I have had a few memorable sightings with the telescope, even though it is aimed at beginners. The first night I used it I saw the rings of Saturn and then Jupiter and four of its moons.

 

 

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Welcome and you have definitely some to the right place for quality, friendly advice. I have been pointing a lot of folk to SGL from the Facebook groups. There are a lot of people asking bginner questions and I believe generally the quality of advice given here is better than a lot of the FB groups. 

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3 hours ago, Spile said:

Welcome and you have definitely some to the right place for quality, friendly advice. I have pointing a lot of folk to SGL from the Facebook groups. There are a lot of them asking questions and I believe generally the quality of advice given here is better than a lot of the FB groups. 

100% agree with you here, the sgl forum is so friendly, informative and helpful. It's the only place I trust to give me the right advice and help, I'm a beginner still and love learning on here for our fascinating hobby/obsession. 

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I've been using telescopes for nearly 50 years and I think I'm fairly adapt at it but even I get frustrated at times. Cold, damp and dark conditions is a perfect recipe for awkwardness and mishaps , if something can possibly go wrong it probably will. I often use   ungentlmanly language under my breath (and sometimes out loud in the wee small hours). The biggest frustration (apart from cold hands dropping eyepieces) is dew.  Get a hair dryer for finders and eyepieces on bad nights they can dew up within minutes and sometimes it can reach the telescope optics. Beware a hair dryer can be as loud as a jet taking off in the middle of the night,(and use a contact breaker even though I don't).

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As a beginner, I found a combination of my RACI, rigel and definitely the help of stellarium or astro maps for star hoping. It has taken me just under 1hr the other day to locate some nebulas, and the next time it was quicker. The other night, i could hardly locate my targets as a result of poor viewing; that can have a huge impact on your star hoping. I could locate all of them last night with better viewing conditions. So,  be patient, take your time and enjoy, there is always going to be another night if things do not go to plan. As other said, having an easy target at the end of the night makes up for a not so successful searching session..

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34 minutes ago, Les Ewan said:

I've been using telescopes for nearly 50 years and I think I'm fairly adapt at it but even I get frustrated at times. Cold, damp and dark conditions is a perfect recipe for awkwardness and mishaps , if something can possibly go wrong it probably will. I often use   ungentlmanly language under my breath (and sometimes out loud in the wee small hours). The biggest frustration (apart from cold hands dropping eyepieces) is dew.  Get a hair dryer for finders and eyepieces on bad nights they can dew up within minutes and sometimes it can reach the telescope optics. Beware a hair dryer can be as loud as a jet taking off in the middle of the night,(and use a contact breaker even though I don't).

And your wise words are very much appreciated so thank you.

Interesting that you mention dew as a major frustration. For me it is ice and the effect it has on the lens of my finder. Well than and the frustration resulting from increasing years. 

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5 hours ago, SaberJeff said:

Uranus, which I photographed on my cell phone a few days ago, is gray.

Than you all for the additional advice.

I've been fortunate enough to see Uranus three times since last Thursday. I was able to check that I was looking in the right place by using Sky Safari. Looking at the planet, it's just a minute smudge in the sky, below Mars. It doesn't seem to sparkle like a star. I'd say the colour is grey blue.

I'm still having difficulty finding dim stars using a red dot finder. I've turned the red dot down so that it's a pale pink. I set the finder so that the top of the objective is underneath the star. I then move the front of the telescope gently upwards while looking through the main telescope eyepiece. I don't often find the star I want . It's easier finding the bright stars such as Rigel and Sirius.

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12 minutes ago, keora said:

Than you all for the additional advice.

I've been fortunate enough to see Uranus three times since last Thursday. I was able to check that I was looking in the right place by using Sky Safari. Looking at the planet, it's just a minute smudge in the sky, below Mars. It doesn't seem to sparkle like a star. I'd say the colour is grey blue.

I'm still having difficulty finding dim stars using a red dot finder. I've turned the red dot down so that it's a pale pink. I set the finder so that the top of the objective is underneath the star. I then move the front of the telescope gently upwards while looking through the main telescope eyepiece. I don't often find the star I want . It's easier finding the bright stars such as Rigel and Sirius.

Yes, the RDF is fine for things that are bright, but it is a pain when you are trying to get a 'scope lined up with a feint object, I recounted my frustration here :

Heather

 

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An issue that you might have is that the RDF "window", being very small, is going to be highly prone to dewing. If it dews up this will prevent you from seeing fainter stars through it. You might find it needs a quick wipe sometimes before you try to aim at something (you shouldn't wipe mirrors or lenses, but a cheap RDF should be ok). 

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I can testify that patience does pay off and it makes more sense to me to keep practicing in order to get the minimum potential  and limits for my existing kit.

Attaching a disused phone mount I had for my pushbike on my telescope has helped considerably. The SkEye app (indirect mode) helps me locate objects really quickly.

Last night without using my straight-through finder* I was delighted to locate Bode's (M81) and the Cigar (M82). This was despite the best efforts of the moon to spoil the party.

* Given the lack of brighter stars in this region, I am not sure it would have helped.

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I tried binocular observing while my scope and mount were being used for photographing M42.  I managed Mars and Uranus and Andromeda, but gthey were all close to the moon and suffering from moon-glow.  The Pleaides were even worse!

I therefore turned round and looked east and found it was easier to find targets there, where the moon glow was less.  I managed M35 in Gemini and M44 in Cancer.

After the photographs were done I used the GoTo on my EQ5 to find some other fainter items but those were 'cheating' as the mount did all the work.

NGC2264 - Christmas tree cluster

NGC2301 - Hagrid's Dragon / Great Bird / Copeland's Golden Worm

 

It's not easy starting off and you do need to be both patient and methodical in your movements to minimise shake etc.  Well worth persevering though.

 

 

 

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22 minutes ago, savcom said:

After the photographs were done I used the GoTo on my EQ5 to find some other fainter items but those were 'cheating' as the mount did all the work

Cheating ?... depending on light pollution it was probably a necessary evil , shall we say . But finding the targets oneself does give satisfaction 

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