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Walking on the Moon

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Hi there everyone,

After some help and advice on viewing planets and what lenses are the best.

I currently have an Orion spacepeobe 130st, and its a great scope. I have collimated it to the best of my current ability and i have been getting some decent views of starts and the moon. 

Last night i focused on viewing jupiter. I placed my 40mm lense into my scope and had a look. I could see the moons around jupiter and another star. I placed a higher mag lense in and a HD filter on. Jupiter just seemed too bright and i was struggling to get any focus on it, or detail. Ive been told that with my telescope is capable of producing a really nice imagae of planets but so far ive been somewhat dissapointed.

Can somebody advise me on what i may be doing wrong or what lenses are the best for planetary viewing.

Thanks, Joe 

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do you ND filter, rather than HD?

A 5mm in your scope will give you x130, which is a good mag for Jupiter and well within the capability of your scope. What length was your other EP?

Your 40mm will only give you 16x so you won't see much detail with that - but it is a nice wide field EP.

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Its a UHC Filter. I was sold it under the impression i would see better detail on planets. The second lense i used was a 4mm Plossil skywatcher. i seemee to get very high mag with it but not detail


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The see much of Jupiter you need to be consider something at 50x or 60x as a minimum, should then see the planet and 2 bands - may depend on the atmosphere. 80x and 100x woud be better but start out at the lower end. and work up.

Seems 130st stands for "Short Tube", but the specification does not imply a Bird-Jones design. The description is slightly odd. Will assume that it is a straightforward 130mm f/5 parabolic reflector. Should get 80-100x fairy happily, 6mm eyepiece I suggest. The 4mm is going to be too much for the scope and in a way for the eyepiece itself. Short eyepieces need to be good, and 4mm is short.

UHC filter OK for some DSO - nebula but usually not a planetary filter in application. Which UHC make is it?

Think you need to start the awful action of investing in eyepieces. BST Starguiders are usually suggested, if you wanted a single one at first then try the 8mm BST Starguider - nice all round performer. For more magification you could look at the Altair Lightwave at 6mm (the £55 one). Seems to be 2 Altair Lightwave branded eyepieces one is £55 the other about 3x the cost.

Edited by ronin
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Hello Joe, and welcome.

I have an Orion 150mm f/5, just 20mm larger in aperture.  Jupiter appears as this through one of my eyepieces...


I then use one of these to dim it down...


You attach it to the eyepiece, and then adjust the amount of light from allowing only 2% up to 40% through to the eye...


After I snapped that shot of Jupiter, I increased the magnification, but Jupiter was still a bright, white ball.  I then attached and adjusted the polariser, and lo and behold, colours and detail of the planet's surface appeared.  During a few moments of exceptional seeing, when the atmosphere steadied, I saw the festoons and whorls within one of the planet's equatorial belts; a shattering sight.  But patience is required when waiting for those moments of steady seeing, and when the planet appears tack-sharp.  

Motorising the RA-axis mount makes that much easier, although doable still with the axis' slow-motion control.

The polariser may also be used when observing the many phases of the Moon, and the many levels of light of same.  It can also be used to dim down the Sun, during the day, but only with a safe  solar filter attached to the front of the telescope in addition, like this...


The polariser itself will not  block out the Sun's harmful rays, and to make that clear.

A 130mm aperture is capable, in theory, of 250x, but in practice, given a finicky atmosphere, 200x and below are more practical.  Also, when observing at the higher powers, the collimation must be spot-on, and for best image quality.  The more precise the collimation, the sharper Jupiter will be at those higher powers.    

Edited by Alan64
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The manufacturer is going to give you a good telescope for the outlay; but the eyepieces and other accessories are intended to get one started with the kit.

650mm ÷ 150x = a 4.3mm eyepiece...

http://www.365astronomy.com/4.5mm-the-planetary-uwa-eyepiece-58-degrees-1.25.html (144x)

http://www.365astronomy.com/4mm-the-planetary-uwa-eyepiece-58-degrees-1.25.html (163x)

http://www.365astronomy.com/3.2mm-the-planetary-uwa-eyepiece-58-degrees-1.25.html (203x)

Those eyepieces have built-in barlows; many of them do, and to accomplish the higher powers whilst providing good eye-relief and a wider view.  You can choose something like those, or get barlows...



With barlows, you can double(2x) or triple(3x) the power of any eyepiece.  Combine the 2x barlow with the 10mm Plossl that came with your kit, and for an effective 5mm(130x); combine the 3x barlow with same, and for a 3.3mm(197x).

With the 2x barlow listed, you can get an 8mm(81x) eyepiece, and have a 4mm(163x), too.  81x for a globular cluster or two, and 163x for Jupiter and Saturn; Saturn especially, and both as the year progresses. 

Edited by Alan64
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