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what am i doing wrong?


rpmiller78
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i just cant seem to figure out what i am doing wrong. the only dso object i have seen through my scope is m13. last night i had great sky's(there was madison light pollution near by). i, for the life of me, could not find the ring nebula. i had my scope pointed at the right spot. i just could not see it. then i tried for m13 again, and couldnt seem to locate that either. i was using my 40, 25, and 17mm eyepieces. i am a noob and my averted vision skills are not good yet. add along to that the fact that i have terrible eye sight in the first place. any tips from you guys would be greatly appreciated. thanks.

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Perhaps if you haven't already, then consider fitting a telrad and use this in conjunction with your finder scope and low power eyepiece. Download and print-off the messier list Telrad charts. Ensure that your eyes are fully dark adapted takes between 30 - 45 minutes.

Also consider starting a session by using a pair of binoculars to familiarise and orientate yourself to the sky and perhaps pick out a few objects to.

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Now I'm not being patronising but have you checked out that the finder scpe is still aligned properly? It's very easy to knock one inadvertently whilst packing a scope away or getting it out, or maybe it's been knocked onto whilst it's being stored.

Just an idea .

You should be able to make out M57 even from areas suffering pretty bad LP it's that bright, but remember its very small so it may appear almost stella in very low power eyepieces.

The Telrad suggestion is a good one, they can really help with object location.

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I totally agree with the idea of finding a few items with bincoculars. That way you can familiarise yourself with the star hop to each new object.

If you found M13 reasonably easy, you should be able to see other DSOs. The Ring nebula has quite a high surface brightness and should be clearly visible in an eight inch scope with patience.

DSOs do become easier to find with practice but Stellarium or Cartes du Ciel will help.

Happy hunting!

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The DSOs you mention are very bright. They will punch through light pollution and you won't need averted vision to see them. You can easily make them out with direct vision. If you're not seeing them then it's simply because you're looking in the wrong the place. As the others had said, a Telrad will help, as will practice. Perhaps after initially pointing the scope with the finder you are moving it too much whilst searching at the eyepiece?

In what sense if your eyesight terrible? If you're just short-sighted, the that's irrelevant since you effectively correct for that with the focus knob. Even if you're, say, astigmatic, you will easily be able to pick out these objects. Remember that the ring nebula is small. If you're expecting something large, you may miss it.

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The Telrad and Stellarium will help a lot, as will practice, using a low power EP, a lot of clusters ect appear to be a slightly out of focus stars there that small, once found and high power used you get to see the real beauty, just practice.

Edited by Tinker1947
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Just an additional thought, that perhaps your lowest power eyepiece - 40mm, might be a touch too low (with your scope) for your light polluted skys, (working more favourably under darker sky conditions) thus washing out the sky a bit, with little contrast for detecting objects.

Therefore something around 30mm, then switching to your 25mm might perform better.

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Like Steve (swamp thing) mentioned above, i suggest you check on a bright star or a planet just to double check that your finder and telrad are pointing in the right direction. Once that is cleared, checking the general location on a star map and looking throught the telrad and the finder should be enough. I do this and look through my 24mm from here in Los Angeles with horrible light pollution and find the objects without much trouble.

Just keep in mind that if you live near a big city, some objects will not be available for you. Things like wide/faint nebulas such as the veil and North American, and galaxies are most likely not going to happen.

But bright things such as star clusters, bright globulars, and bright nebula like Orion, the Ring, Lagoon, should all be within your reach.

Good luck!!!

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Don't feel bad about not being able to hunt down DSOs as a beginner. We all have the same thing in our past when we were starting out. Once you know where the objects are (which comes with experience) you will start to locate them very rapidly.

As has been mentioned in the other comments, the two DSO’s you mention are actually quite bright and well within the capabilities of your scope to see.

If we first take a look at M57, the Ring Nebula, the primary concern to be aware of is its small angular size. It measures only 1.5x1 arc minute (the full moon is approx 30 arc minutes across – 0.5o)

To put this in perspective, you said you used the 40mm, 25mm and 17mm Sirius Plossl eyepieces. The Sirius 40mm EP has an apparent field of 43o which in your scope gives a magnification (focal length of the telescope[1200mm] divided by focal length of the EP[40mm]) of 30x. The field of view is calculated as the apparent field of view [43o] divided by the magnification [30x] so in this case it would be approx 1.4o. There are 60 arc minutes in one degree, and almost 85 ring nebula’s would fit across the field. So at this magnification M57 is more likely to appear almost stellar (star like) so you may have had it in the field and not even realised. That is not to say you should not use the 40mm, you should, as it makes star hoping much easier. Once you think you are on target, by comparing the star field you see with a star chart, switch to a higher power EP.

The other two Sirius EPs have an apparent field of 53o, which will give magnifications and actual fields of view of 48x and 70x and 1.1o and 0.75o for the 25mm and 17mn respectively. The interior hole becomes pretty easy to resolve at 100x, so you might want to consider using a shorter focal length eyepiece for higher power once you believe you have M57 in view.

M13 is far larger (approx 20 arc minutes across) and should have been obvious, even in the 40mm EP. Which leads to the conclusion that you finder may have become misaligned with the telescope. The alignment tends to be fairly fragile and should be checked often. You can use a distant object during the daytime if you want to check the alignment before fine tuning at night on a bright star. Given that even with the 40mm EP the actual field of view is still relatively narrow, it would not take much of a misalignment of the finder to not see the same field of stars as you believe you are pointing at.

Edited by DirkSteele
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i was out at an observatory a few weeks ago and there were some experienced guys there. they said i had it in the right spot and that i should be able to see it. i think i am looking for something much larger that what it is. i did see it through the observatory's 14 inch telescope.

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i was out at an observatory a few weeks ago and there were some experienced guys there. they said i had it in the right spot and that i should be able to see it. i think i am looking for something much larger that what it is. i did see it through the observatory's 14 inch telescope.

The 14" scope would have had a much longer focal length so the magnification with similiar EPs would have been much higher and the field of view much narrower so I can see how you would have thought the objects were larger than they actually are. Once you think you are in the right spot try using one of the shorter focal length EPs like the 10mm or 7.3mm.

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well, my scope was out of collimation the whole time(facepalm). i got it brought back in enough to where i could actually find the ring nebula. i have been traveling a lot with my scope. i should check that way more often. i contacted the local planetarium, and the guy who works there is going to help me dial it in further and give me some tips. this works out well, because he was planning to check the collimation on some the planetariums telescopes.

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You can also install a degree circle and an angle finder to make locating objects easier. It's a fairly simple DIY project.

Free apps on your smartphone can display exact coordinates. I rely on this system to locate objects, especially under polluted skies where I live.

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