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I was out looking for m57 near vega the other night using the 25mm wide that comes with my scope,this was my first hunt and im woundering whether theres a ep thats really good for hunting for stuff ie.....the wider the better or is it better to use a red dot to do the work ?

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I think a low powered, wide field eyepiece is useful but even then the amount of sky that it will see will be very small, usually only a couple of degrees, so an RDF and / or an optical finder is needed to get to the right general area.

This is where the Telrad finder scores as it projects 3 circles against the sky of 4, 2 and .5 degrees diameter so you can use these to star hop to the right area with some precision.

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A good star map is essential to finding anything properly. As soon as any eyepiece goes in, you see far more stars than you might imagine and it easier to get lost, especially with a reflector (image inverted and back to front). Telrads are very good but you still need a good map. What map do you use?

James

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hi jbm i use stelerium to find the constelation then center on a bright star then try to star hop but the finder that i have is upside down so im confused to which way to go

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Worth remembering that M57 is unexpectedy small when you see it for the first time. Yes, look for it first with the 25mm, but it will just appear as a small out-of focus star and easy to miss. Once you've found it, then use a higher magnification.

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Worth remembering that M57 is unexpectedy small when you see it for the first time. Yes, look for it first with the 25mm, but it will just appear as a small out-of focus star and easy to miss. Once you've found it, then use a higher magnification.

Luke beat me to it. Some objects (a lot of the planetary nebs) are so small they will evade detection in a low power eyepiece. So a certain amount of star hopping is needed. I use an RDF (Rigel Multi Reticle) 90% of the time in combination with a 32mm 2" widefield eyepiece. This is a great combo for finding a lot of objects. But for the small hard to detect jobbies i switch to an optical finder and a 16mm widefield eyepiece. And then once found, up the eyepiece again to 8-12mm, depending on the object.

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Ok cool stuff....getting a good idea how to go about it next time using diffrent ep s red dots and telrads theres alot of fun to be had in the hunt so its not too frustrating thats why i said no to a goto as a first scope,but will be great when i do find my first dso:)

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It took me a long time to find M57. I first tried to use a straight through finder (that I made from an old binocular lens and binoculars eyepiece) to find it. I also found having to point the telescope in the opposite direction to the image of the star in the finder which I wanted to get to very confusing.

I then splashed out on an Orion RACI (Right Angle Correct Image) 9X50 finder scope. This shows the constelations the 'right' way round, as in binoculars.

This helped enormously. It was easy to aim the finder scope at Vega in the constellation of Lyra, then find the stars Sulafat and Shellak in the same constellation and aim the finder scope to a point in the centre of an imaginary line between the two stars.

M57 was then visible in the finder scope.

It does look like a fuzzy star, but it is only slightly fuzzy, so it is best to move the finder scope around a little and use averted vision, as this helps to spot it.

Then I used a 25mm eyepiece and put M57 in the centre of the field of view. I then used a high power 7mm eyepiece. I could then see the ring shape and only at this point was I sure that I had found M57 at last!

I also find Stellarium very useful.

I also use finder charts, with a circle drawn on the chart to represent the stars seen through a 50mm finder scope.

I mainly use the charts in a great book called Illustrated Guide to Astronomical Wonders, which I can highly recommend. It has finder charts for all the constellations.

I also use some finder charts for the all the Messier objects which are free to download. When I manage to find where I have saved them on my computer I will post the details of where to download them!

I can't comment on Telrad finders etc. as I have never used them, I am sure they work well, but I find the finder scope I have sufficient.

Good luck with finding M57 and don't give up!

After finding M57 once, I can now go straight to it every time!

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I also use finder charts, with a circle drawn on the chart to represent the stars seen through a 50mm finder scope.

time!

I was looking for M57 the other night too. It beat me! Try and track where the object should be with binos first I find helps. Then you know at least familiar stars around. Does Stellarium, or any other software for that matter overlay the FOV? This would also be a great help I believe....

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I also use binoculars to find where to point my telescope.

The finder charts for the Messier objects which I mentioned before are called a Star Hopping Guide to the Messier Marathon by Robert J. Hawley, and can be found at www.robhawley.net, just scroll down.

They are free to download and include finder charts for M57 and M27 the Dumbell nebula.

You could then print the ones you need out. I used them to find M27, which I found really difficult, but then I live in London with it's light pollution!

I don't know anything about overlaying Stellarium with finder charts, but I am useless with computers!

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I find the 1 degree FOV I get with my 25mm eyepiece is enough to find things with the help of my goto mount. I'd like a wider FOV for appreciating open star clusters - I have yet to conclusively find a single one, even though they are big and bright. Their shape is undetectable in my tiny FOV.

I can see the attraction of the hunt in finding things by star-hopping, but I get enough intellectual stimulation just from getting my goto working adequately! lol

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Glad to know its not just me, I was hopping around Lyra for ages the other night and M57 certainly evaded me despite a wide-ish EP (perhaps the problem according to Russ?) and a decent RDF. Maybe just not enought light getting to my 72 meg in midsummer AND a biggish moon. But (so far) clear up here tonight so will try again from the garden with a bigger newt, following all the good advice above.

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I don't know anything about overlaying Stellarium with finder charts, but I am useless with computers!

I have had a look and yes you can user define the actual view one can see thru the scope. You can even user define the eyepieces- very very cool.

xmal

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M57 is sooo small, just imagine how big a really small DSO would appear in your selected eyepiece and it's about 1/10th the size of that :rolleyes:

I managed to find it after a short time spent pointing to roughly where I though it would be and scanning around with my widest EP, more luck than anything else. I'm not good enough to star-hop and in any case I don't have a decent map, just stellarium. There is software, 'star calc' I think it's called, that lets you print out maps to whatever magnification you fancy, but I have no idea what my limiting magnification is currently and I'm waiting for some darker nights before giving it a proper go.

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M57 is sooo small, just imagine how big a really small DSO would appear in your selected eyepiece and it's about 1/10th the size of that :rolleyes:

I managed to find it after a short time spent pointing to roughly where I though it would be and scanning around with my widest EP, more luck than anything else. I'm not good enough to star-hop and in any case I don't have a decent map, just stellarium. There is software, 'star calc' I think it's called, that lets you print out maps to whatever magnification you fancy, but I have no idea what my limiting magnification is currently and I'm waiting for some darker nights before giving it a proper go.

EN209- I have just been playing around with Stellarium Ocular plugin and you can simulate your FOV and overlay it onto the computer screen. Not only that you can invert on both axis to recreate what you would actually see thru the scope. This is exactly what I was looking for.

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Yeah I've been playing around with that too! Problem is, I've got no idea what the focal length or AFOV of my EPs are, I bought them second hand. This isn't something that can be calculated from available info such as their aperture and the measurements of my scope, is it?

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M57 is sooo small, just imagine how big a really small DSO would appear in your selected eyepiece and it's about 1/10th the size of that :rolleyes:

I managed to find it after a short time spent pointing to roughly where I though it would be and scanning around with my widest EP, more luck than anything else.

That was my experience also. I was using a 30mm EP and i overlooked M57 a couple of times before going back to investigate with a higher powered EP.

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Yeah I've been playing around with that too! Problem is, I've got no idea what the focal length or AFOV of my EPs are, I bought them second hand. This isn't something that can be calculated from available info such as their aperture and the measurements of my scope, is it?

Probably not. I am in the same boat as I bought my kit second hand too. You could put in a range of values to simulate a close approximation of what you are actually seeing thru the finder. Once you have those values it should be relatively easy to tweak values further to replicate the finder. GL.

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Calculate your FOV? You can look at the moon tonight - it is half a degree, that will give you a rough idea.

Then you can do the star drift technique. A star at the celestial equator drifts at a certain rate, so if you time how long it (eg Regulus) takes to drift accross your field of view you can accurately calculate your FOV. If I recall correctly a star on the celestial equator drifts at 0.25 degrees per minute (360 degrees divided by 60 divided by 24).

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I think that like many things, once you've seen it, you cannot then understand how you missed it in the first place - there's nothing like experience!

these maps really helped me Messier Maps even if you don't have a Telrad they will help you get into about the right position.

I find that the Telrad gets me 66% there, the optical finder about 90% there and I find a wide field low power eyepiece gets me the rest of the way there (usually). as others say, then use higher power if you can to see more detail.

I can get straight to the Ring now with just the Telrad.

you'll get it eventually but it is small. this is one target I went for first and still look at every time I observe!

here's my tip to find it which will hopefully help:

get Vega in the optical finder

you'll see the close pair of stars which is the double double.

on the other side of Vega i.e. to the right and down a bit you'll see two widely spaced stars with another star about a third from one star - don't confuse this with the wide pair just under Vega - I did this for a while myself!

go to the middle of the two third gap and put your finder in the middle of this

then check your eyepiece and I bet the Ring is in it.

this map http://www.astro-tom.com/messier/messier_finder_charts/map8.pdf shows this a little more clearly than I can describe

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Calculate your FOV? You can look at the moon tonight - it is half a degree, that will give you a rough idea.

Then you can do the star drift technique. A star at the celestial equator drifts at a certain rate, so if you time how long it (eg Regulus) takes to drift accross your field of view you can accurately calculate your FOV. If I recall correctly a star on the celestial equator drifts at 0.25 degrees per minute (360 degrees divided by 60 divided by 24).

Excellent ideas, I'll give them a go :)

When set up, this ocular plugin for stellarium really will be an excellent tool for a n00b like me :rolleyes:

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Excellent ideas, I'll give them a go :)

When set up, this ocular plugin for stellarium really will be an excellent tool for a n00b like me :rolleyes:

TBH, the Ocular is all you need. Play around with the values....

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