Too many stars - please help a beginner

[adam from dorset]

Taking SGL at its word that there is no question too stupid to ask ...

I am gradually learning to recognise the brightest stars and the constellations as seen with the naked eye, and so to try to navigate from a known point to find others. I have two related problems which I expect everyone has learned how to overcome so please can I tap into the collective experience.

1. The view through the telescope eyepeice is inverted and as it pans accross to find a target the view moves the "wrong" way. This I expected and for really distinctive objects like a planet I can cope, but I am finding it very difficult to distort my mind to accomodate. So for example I "know" by thinking carefully about it before putting my eye to the eyepeice which way to move the scope to track from one star to the next in a familiar constellation like cassiopea but I stiil can't do it, especially when in a contorted position. What techniques are there for learning to reorientate my perception? I plan to get a diagonal for the finder which may help a bit.

2. With the naked eye a constellation consists of a few distinctive bright stars. Looking at one of these through the scope at low magnification the field of view contains hundreds of stars of varying brightness, but all so bright that I can't work out which is the "genuinely" bright one. Even through the finder it is difficult but usually I can eventually centre on the most likely candidate. What techniques are there to callibrate my eye's brightness scale? Might a filter help?

Thanks

[tonedeaf]

so...where to begin?

get a goto mount (no sorry, this discussion will go off topic)

oh as you said a diagonal will help!

further...do you have a laptop? get stellarium or an other software to show you the "star"-map

which will help you to get an idea where to look at and what you might see...

(it´s also usefull, when you tipe your scope and eyepiece datas in it will show you a "view" through your ep)

if you haven´t made it yet -> align your finder with your scope during daytime...

try starhopping....

but these are only my suggestions, i´m not a "pro" in "observing"

(the last time i´ve looked through an eyepiece was about a half year ago )

[Schorhr]

Telrad/Rigel and Star map with circles-

Or print flipped maps with Cartes du Ceil ;-)

[E621Keith]

1. Inverted image - you will get used to it. If you use a refractor, SCT or Maksutov, a regular star diagonal will correct up and down, but the image will still be left right reversed. You can also get erecting prism which will flip everything the right way round, but they are optically inferior to regular non-erecting diagonal.

2. Get a unit finder and possibly a finder scope. Use the unit finder (e.g. Telrad, Rigel, red dot finder etc...) for rough pointing and then fine tune with the finderscope. This should get the desire star into the FOV of your main scope.

[glowjet]

I do not know what finder you have, but a correct image finder 8x50 or 9x50 either straight through, or right angle, if you suffer from awkward viewing positions, could help as this will give you the image as you see it in the sky and of course will be the same orientation as any star map you may be using

[scarp15]

Once you have aligned onto one, the brighter stars are distinctive and will enable you to gauge your position. A telrad or similar is probably the easiest way to do this. If you are manually moving the scope, nudging or using slow motion controls, you do tend to become accustomed to the reversed image.

[blueroom]

Ah it's not just me then

I was having the same problems you've described, I then bought a Telrad finder scope and it made it so much easier. I also have a RACI which is a lot easier to use than the standard finder scope.

[rwilkey]

Hi, I find a RACI (Right-angle, corrected image) finder indespensible and have an 8x50 on both my scopes, the orientation through the scope you get used to after a while, but I still find myself going in the wrong direction sometimes, we're only human.

[Phillithevicar]

Yep I'm with you on this (newbie too) Your second point is the bit I have most problem with! Looking at the stars=Ok, looking through the viewer=ok but now I see a lot more, then looking through the ep and everything is just mind blowingly (sp) bright and I lost the original target object.

I have sterllerium plus 3 apps for pointing in the right direction but the magnification at anything below say 25mm renders my powers of direction useless.

Oh Hum onwards and upwards!!

[Astro_Baby]

Its a large newt you have thyere and large newts, especially on EQ mounts, can be marish to work with especially on an unpowered mount.

First off get something like a redt dot finder or telrad. With some experience these can work well as you are seeing at no magnification and with some practice you can keep both eye open and the red dot will appear as if by magic on the sky in your vision.

Secondly the reason why you are in a strange position is probably due to the newt being on an EQ. You need to rotate the scope in its rings to get to a good position. With a big heavy newt (or even a small light one really) you need a ring rotation system. Look up Wilcox Rings on Google or take a look here to get the idea http://www.astro-baby.com/articles/rotating%20rings/Rotating%20Rings%20Project.htm

This might help with reducing the amount of yoga you do with a telescope.

Thirdly a basic straight through finder can also work with both eyes open,. Acquire the finder image in your right eye and then open the left eye, with a bit of practice you can see both the wideangle view that your normal eyesight is showing with the finder view superimposed.

Hope thats some help.

[bish]

I use a 9x50 finderscope and a good starmap/software combined with binoculars. I start with the brightest star fairly close to where I want to look.Then I star hop across using the bins to check against the finderscope. When I'm in the right area it's useful to know the field of view of the ep and look for a distinctive pattern next to the brightest star close by. You ned to have quick access to a decent star map

[todd8137]

A decent straight through 9x50 finder ,beleave it or not after a few weeks you will get used to go in the oposite way and it becomes normal but its very of puttin to start with stick with it

pat

[adam from dorset]

Thanks for all these comments - things to work on there. It's reassuring to here that others-not just beginners - have the same difficulty.

I'm using a 10" Newtonian with a red-dot finder, a lowpower finder, and a high power finder. By working sequentially I can align the scope onto a target.

further...do you have a laptop? get stellarium or an other software to show you the "star"-map

which will help you to get an idea where to look at and what you might see...

(it´s also usefull, when you tipe your scope and eyepiece datas in it will show you a "view" through your ep)

I am using Stellarium on a laptop. How can I customise it as you sugest - this sounds useful.

Or print flipped maps with Cartes du Ceil

Thanks Schorhr, I didn't know this facility was available. I'll investigate.

Inverted image - you will get used to it.

Thanks ; I think I knew really that this is the right answer! Using a correcting prism somehow seems like cheating.

I also have a RACI which is a lot easier to use than the standard finder scope.

How does this differ from a "Star Diagonal"?

Secondly the reason why you are in a strange position is probably due to the newt being on an EQ. You need to rotate the scope in its rings to get to a good position. With a big heavy newt (or even a small light one really) you need a ring rotation system. Look up Wilcox Rings on Google or take a look here to get the idea http://www.astro-bab...ngs Project.htm

This might help with reducing the amount of yoga you do with a telescope.

This is really useful. My scope has this system already but it didn't occur to me to use it to change positions during a session because it is quite clumsy to do - I have just tried to set it in a good compromise position. I will work on making it easy to rotate the tube in its clamps. Maybe new felt will also help. One problem with this though - the balance is significantly changed if thre tube is rotated 180 degreesso that the finders and eyepeice/focusing unit move from near the mount to away from it.

Thirdly a basic straight through finder can also work with both eyes open,

I am used to this technique from microscope work. The problem I have so far had with it is that I wear varifocal glasses so it is hard to resolve both images - without them I can't focus on the sky and with them I can't focus on the finder image! I will work on this one.

[Astro_Baby]

"One problem with this though - the balance is significantly changed if thre tube is rotated 180 degreesso that the finders and eyepeice/focusing unit move from near the mount to away from it."

Any newt will have an imbalance in this regard when its loaded up on a mount. I wouldnt have though the size of the old mount you have it on would cause problems. The only perfect balance point would put the EP in a hopeless position for most observing.

Old style newts on EQs (and yours may just have this) used to have a rail down the newt with a weight that could be moved about to correct the imbalance. I have no experience of that as it kind of predates me a bit

All scopes to some extent suffer this on an EQ mount though - newts perhaps more than mots because the EP is sticking out the side of the scope and the EP weight can be significant with modern widefield EPs.

I would not worry too much. I balance mine with wherever the eyepiece and finderscope are at the time and let it go at that. Its never caused a problem so far and thats with EPs that range in weight from very little to humongous and two finders hanging off the scope which are both quite heavy.

So long as the balance on the DEC is more or less ok and also on the RA theres not much can be done about the offset balance caused by newts having their focusers and EPs to one side.

[KenG]

I use both a Telrad and a right-way-round 9x50 finder to find my way around, as others have suggested here. In addition, I have circles corresponding to the fields of view of my various eyepieces, and the finder, scribed onto strips of thin, clear, perspex. Used with Skyatlas 2000, this is a foolproof method of star-hopping. The circle on the page tells me exactly what I should be seeing, and if I'm off target, it's easy to work out where I am - visually speaking that is!

[tonedeaf]

....I am using Stellarium on a laptop. How can I customise it as you sugest - this sounds useful.

there should be a "tab" called Oculars (should be in the upper right)

and then the button with the wrench -> options

[Pyrodave]

there should be a "tab" called Oculars (should be in the upper right)

and then the button with the wrench -> options

If you have trouble just Google stellarium ocular tutorial

[adam from dorset]

Just to update on progress:

1. Stellarium ocular plug-in first came out with version 0.11.0 which needs mac os 10.5 to work. Unfortunately I run os 10.4.11 and can't upgrade, so the version of Stellarium I am using - 0.10.2 - is the newest compatible one. So no further help there unforunately.

2. Star diagonal on order so this will help.

3. Astro-baby's point about rotating the tube in it's rings is helpful. I have experimented a bit and have on order some self adhesive teflon tape which I intend to stick on the inside of the tube rings instead of the tatty felt and also on the opposing surface of the tube. The tube should then slide round nice and easy when the clamps are slackened. Will report later whether it works.

[planet15]

I use an Ipad app called "Night Sky", and it seems quite good.

[dragonlord]

I second the idea of using a star finder app on a tablet or phone, as they all have a follow sky feature. Some of them also have a search option that will enable you to find a star and the follow the arrow on screen till you get to it.

I'm currently using redshift which is paid for and has satellites and metors as well as the standard visible and deep space objects.

[Stargazer_00]

bit late coming to this but on your second point I've never had a problem identifying the bright star at the eyepiece. They are usually much more distinct than those around them. similar in size perhaps but so much more intense like looking at a 5w bulb from 100 yards compared to a 1000w bulb at the same distance. The size is the same but the intensity of the point source is much brighter. If you are unable to detect this magnitudal difference then practice on known stars until you can. It's a very important skill for visual observation and navigation at the eyepiece. pick mizar and alcor in ursa major for instance. a very bright star near many other bright stars.

As far as mental gymnastics this is something that just comes with practice like above. It's funny in fact that when I went to a corrected image finder from one that was inverted and reversed it took me a long time to relearn left was left and up was up to navigate with the finder. felt alien having the finder move differently to the way the eyepiece moves and can be more challenging to find objects with one brain orientation and then track with another at the eyepiece.