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Hi

I just spent about 20 minutes outside trying to get my powerseeker 76 to actually bring a star into it's field of vision and failed miserably.    I only had the 20mm eye piece in as well so should have had a decent field of vision...what am I doing wrong?

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All the caps are off, I can see "stuff", I thought the finder scope was aligned but may well be out...just got really annoyed as I had my 2 kids itching to see something out there lol.  May have to try aligning the finder scope again tomorrow.  It may have helped if the moon was up as I would have had something bigger to look at first time out.

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Hi Muttley,

Firstly I would align your scope properly with the finder in daylight tomorrow.Try to use something at least half a mile away, an aerial maybe. Use your longest focal length  eyepiece, and make note which way you turn the focusser in order to achieve a viewable image. I think you will be ok after that, else it sounds like collimation time.

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I'm used to focusing challenges on a low end DSLR that I whacked some old Olympus glass on so that should be ok, it's just finding the item in the first place that I am struggling with.  If the moon had bothered to show it's face earlier, I could have tried on a significantly larger (closer) object.

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Check the finder alignment as has been said.

Also the 20mm will give a mag of 37x with your scope (76/700 scope).

I assume the eyepieces are not plossl's, they do not hand out plossl's thesse days, so the eyepiece may be 45 degrees not 50, it may be less then 45.

So the field of view is likely about 1.2 degrees. That is not actually a lot especially on a reflector as you are looking into the scope at some odd angle. At least on a refractor and SCT you tend to be positioned to look along the scope, it is a lot easier to have an idea of where the scope is actually aimed on these, not so easy on a reflector.

Cannot suggest much other then check finder alignment, practise or/and a 32mm plossl for as wide a view as reasonably possible. I went for the last option on a Mak I have. Found I couldn't align the thing and next day bought a 40mm plossl. If I recall the view through a 40mm is about 0.1 degree wider then with a 32mm, and all I wanted was as wide as I could get.

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Hi Mutley76...... using your largest  Eyepiece, put that in the telescope and search for something far away in the distance, the further away the better. When you find a suitable target, lock the telescope in that position. once locked, just ensure the image is still central.

Now its time to look through the finder scope, using the adjusters on the finder scope, adjust the finder so that you see the exact same image as the telescope is showing. Once the two images are centred and look the same, the telescope is aligned with the finder, or vice versa.

The more accurate the alignment of both the telescope and the finder, the easier targeting will become. See how it fares with the shortest local length eyepiece/highest power. There may still be some scope for adjustment. Once its set, anything you find with the focuser will be central in the eyepiece. 

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After performing an initial daylight alignment on a distant object, start with a wide FOV illuminated reticle EP and the brightest star you can see. Center the star in the finder then check what you see in the EP. Even if the star isn’t centered or focused, looking through the EP will often reveal the “grey edge of a donut” indicating an out of focus star (may be quite dim initially). Start adjusting focus and the donut will either begin to shrink or grow. If it’s shrinking and getting brighter you’re focusing in the right direction but you’ll need to slowly slew the scope as if trying to center the “donut hole” in the crosshairs as the outer edge moves from the FOV. If you happen to spot a brighter “donut” nearby, go for that one instead since you already know you’re trying to align on the brightest star you can see. Eventually, the brightening disc will resolve into a point of light at which time you should center it in the crosshairs of the reticle EP.

Now quickly check the view in the finder and center the star in its crosshairs by adjusting the thumbscrews. Now quickly look back through the EP and the star will have moved and how much it moved will depend on how well the mount is tracking. Patiently keep going back and forth between OTA and finder while keeping the star centered in the OTA’s reticle EP and adjusting the finder until it and the OTA are as perfectly aligned as you can get them. In this way you can be confident - if the finder is aligned with the OTA and the object is centered in the finder– it’s also in the EP's FOV even if you can’t see it and that’s what happens when the focus is way off. After completing this process is also a good time to align your laser pointer (if you use one) with the finderscope since for manual slewing – a laser/finderscope combo is hard to beat.

Hope this makes sense as it has really helped me. Getting your finder and OTA as perfectly aligned as possible will make everything you do much easier and will put the question of “Am I really pointing at the target?” to rest once and for all...  :smiley:

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I have been out in the back garden today, could see hundreds of stars with the naked eye, but nothing at all through my telescope (yes all the caps were off). I seriously think I need help with this, surely if I can see stars all over the sky, I should be able to see them through the scope...

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Hi Muttley,

Can you see anything through the viewfinder??.  Also if you point the scope at a bit of sky you should see lots of stars, take some time to make sure you are focussing correctly... After that if you still cannot see anything its time to find your local astro group and find someone who can give you a bit of hands on help.

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The telescope only shows a tiny section of the sky so it will show fewer stars than you might expect. When far out of focus, you may well see nothing. The moon is now up early in the evening, it might be a good idea to try that as a target.

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I think I might have to start on the moon. I just spent more time out there, changed from a 15th to a 20th and still couldn't see anything. I did try the moon but that is currently to the front of my house and a street light interfered.

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Right, I have FINALLY got my telescope and finder scope aligned (realised it was so much easier to align them once the finder scope was actually focused!)  Now, what is the betting that tonight is cloudy and I won't see a thing?

Also got stelarium on my phone so that should help a bit too shouldn't it?

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forgive me if this is too obvious, but when you turn the focus knob does the tube actually move? I only ask this because if the locking screw is tight, the knobs will turn without actually moving the tube (on some crayford focusers anyway). Just a thought.

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