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ivanhoe

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ivanhoe

ivanhoe

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Hi everyone im knew to astronomy, i have a level 1 entry telescope celestron power-seeker don't suppose its that good but until i get better at it, it will have to do any advice would be great especially on eye pieces for this tel have a Barlow lens , a 20mm erecting, and a,4mm,....( prob put this in the wrong topic so my apologies to the admin . ( Ivanhoe)

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Putaendo Patrick

Putaendo Patrick

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Welcome! What model is your Powerseeker?

First, the maximun magnification is generally twice the aperture in milimeters. Thus a Powerseeker 114 would be about 228 times max., and the Powerseeker 127 would be 254 times. There's no poiint in trying to push much beyond these as the image quality becomes too poor to be useful. In fact, other than the Moon and planets, most observation is done at quite modest magnifications.

Second, the magnification of an eyepiece is determined by the telescope's focal length divided by the eyepiece number in milimeters. For example if your focal length is 800mm, a 20mm eyepiece will give a magnification of 40 times.

I would probably look for magnifications of around 40X, 80X and 120X, perhaps using your Barlow to push up to 160X and 240X. At the outset, I would look for reasonably prices Plossl eyepieces which would give you roughly this range of magnification. An adequate Plossl new can cost around 20-25 pounds, but as people with more expensive telescopes upgrade their EPs, you can often find good secondhand offers.

Hope this gives you some idea.

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Knighty2112

Knighty2112

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Hi. Maybe first off add a 10 mm Plossl to your eyepiece collection. This Skywatcher Plossl should bring out a little more with your scope, and it's not too expensive either;

http://www.opticalvision.co.uk/astronomical_accessories-eyepieces/sky-watcher_sp-series_super_plossl_eyepieces.html

Remember, the better the eyepiece you have the better the views should be. However, I would start at adding just a few lower priced Plossls first before you go for any much more expensive ones that cost probably more than the full price of the scope you have.

If your Barlow lens is a 2 X Barlow, this would in effect give you six eyepieces; 25mm, 10mm, 4mm. With the 2 X Barlow in with the same eyepieces you will in effect have three more at 12.5mm (25mm EP), 5mm (10mm EP) & 2mm (4mm EP), although the view with the last combination probably won't be very good unless the seeing on the night is exceptionally good.

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jason.p

jason.p

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Welcome Ivanhoe. I think quite a few of us started off with fairly modest gear, it's much more sensible to build up gradually as interest developes and finandes allow. In the meantime you can learn a lot about the night sky with a star atlas, binoculars and just plain eyeballs☺

Best wishes

Jason

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ivanhoe

ivanhoe

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Welcome! What model is your Powerseeker?

First, the maximun magnification is generally twice the aperture in milimeters. Thus a Powerseeker 114 would be about 228 times max., and the Powerseeker 127 would be 254 times. There's no poiint in trying to push much beyond these as the image quality becomes too poor to be useful. In fact, other than the Moon and planets, most observation is done at quite modest magnifications.

Second, the magnification of an eyepiece is determined by the telescope's focal length divided by the eyepiece number in milimeters. For example if your focal length is 800mm, a 20mm eyepiece will give a magnification of 40 times.

I would probably look for magnifications of around 40X, 80X and 120X, perhaps using your Barlow to push up to 160X and 240X. At the outset, I would look for reasonably prices Plossl eyepieces which would give you roughly this range of magnification. An adequate Plossl new can cost around 20-25 pounds, but as people with more expensive telescopes upgrade their EPs, you can often find good secondhand offers.

Hope this gives you some idea.

127 powerseeker

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ivanhoe

ivanhoe

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thank you for the welcome i have been here awhile but work got in the way  to pursue this subject, but now i have more time to discover the sky about me so hopefully i can commit more time to it. i will build my equipment as i go on, hopefully getting better gear, to meet i hope my improved knowledge. I have a set of Bins i use for birding that do the job opticron 8x40s however i would like to know a good mid priced pair that would give me a better range  when i ask for info which forum on here should i use ? thanks   Ivanhoe 

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Putaendo Patrick

Putaendo Patrick

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I borrowed an old and worn Powerseeker 127 recently and found the telescope itself really quite good with better EPs. The mount is, for my taste, too shakey and the EPs and Barlow dubious.

Knighty's advice on selecting EPs in this tread is basically very sound - except I believe your Barlow is X3. Your telescope's focal length is 1000mm for the calculations. Franky I would play around with the supplied eyepieces and barlow for a short while, then chuck at least the 4mm and possibly the x3 Barlow! The 20mm will probably serve for a while, generally less magnification is less demanding. Celestron do in fact offer an EP kit for the Powerseeker, which they probably wouldn't if they themselves had much faith in the supplied EPs!

My own telescope has the same 1000mm focal length, and I use 4 eyepieces and a X2 Barlow to give me the following combinations which will be the same for you:

25mm     40x magnification

18mm     55x

12.5mm (the 25 with Barlow)     80x

9mm (the 18 with Barlow)     110x

7.5mm     133x

5.5mm     182x

3.75mm (the 7.5mm with Barlow)    266x  This is really the maximum magnification for my scope.

And 2.75 (the 5.5mm with Barlow) giving 364x just possible with exceptional seeing conditions.

As you see, I've chosen EPs which compliment my x2 Barlow. There are certainly many other combinations which would give a similar spread.

If there's one EP which I might add, it would be something around 30mm to give me even less magnification and a wider view. Overall, however, I feel I've achieved a good range of magnifications for my needs at the moment. You certainly don't have to have all this to start with. Some people, especially with expensive EPs, prefer not to use a Barlow but for me it's an economical option.

Once again, as with Knighty, I would recommend inexpensive Plossl type EPs, and if I had to chose just one to start, it would probably be in the 10 or 12mm range.

Just my thoughts, others may have very different ideas!

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