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I want more jupiter


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I have found that a blue filter is a fairly inexpensive way to get details to pop and ease eye strain when observing Jupiter. I too know the feeling of enjoying the views of Jupiter recently though so can appreciate your excitement. For me the 2x Barlow on my 13mm is about the highest I dare to go with magnification. In my scope that's 100x.

So what details were you able to bring out. I am stuck with equatorial bands and moons so far but can't wait to see more.

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using the 6mm eyepiece I brought out some of the banding, tonight I used the 4mm eyepiece and brought out even more detail.. this is in my 70mm scope but I am thinking I need to try my barlow lense and see what happens with my lower power eps. the 4 mm eyepiece allowed me to see the banding and what I believe was the red spot.. of course I have been able to see the visible moons as well. I tried for an image but silly me had my camera set up wrong.. I did get good images but no noticable detail.. I am going to be trying again tomorrow as I stayed out till my fingers went numb. 

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I was actually considering on pulling out one of the other two.. my 50/700 actually shows things on the dim side anyways compared to my 70mm scope. I will hopefully play with it. But playing with my 4mm eyepiece I saw more detail.. I don't know what I was thinking trying the 4mm on jupiter but it worked... 

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I was actually considering on pulling out one of the other two.. my 50/700 actually shows things on the dim side anyways compared to my 70mm scope. I will hopefully play with it. But playing with my 4mm eyepiece I saw more detail.. I don't know what I was thinking trying the 4mm on jupiter but it worked... 

Haha,

I tried a 6.7mm with x2 barlow and a moon filter on my 250px and Jupiter looked incredible!  Seen a ton of detail and quite sharp - but much sharper without the barlow - it looked incredible.

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last night we had great views of Jupiter here too, but am still struggling to figure how to get the best views

using my shortest EP (9mm) is was really clear but small (c x45 in my 100mm Newt). 2 dark bands were there if you looked

Barlowing the 9mm (to x90) and the subtle detail was gone. Jupiter was bigger but less clear. Maybe an even shorter EP has to go on the shopping list - or maybe a small reflector isnt up to the job?

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last night we had great views of Jupiter here too, but am still struggling to figure how to get the best views

using my shortest EP (9mm) is was really clear but small (c x45 in my 100mm Newt). 2 dark bands were there if you looked

Barlowing the 9mm (to x90) and the subtle detail was gone. Jupiter was bigger but less clear. Maybe an even shorter EP has to go on the shopping list - or maybe a small reflector isnt up to the job?

Don't be too quick to buy a EP below your 9mm.. if your scope is small then it is probably pushing its limits with a barlow and 9mm.. there is an equation to work out the maximum you should use with your scope. this is a direct quote from an article I just looked up on the subject in relation to the post, (they explain it better than me as I'm just a beginner myself!)  

"As a rule of thumb, the maximum usable power is equal to 60 times the aperture of the telescope (in inches) under ideal conditions. Powers higher than this usually give you a dim, lower contrast image. For example, the maximum power on a 60mm telescope (2.4" aperture) is 142x. As power increases, the sharpness and detail seen will be diminished."

Your probably better off using your 9mm by itself.. perhaps using a moon filter or an 80A blue filter and get comfortable at the eyepiece and giving yourself plenty of time to simply sit and let your eye slowly give you more detail as you naturally pick it up. February 6th is your top night for jupiter so lets hope its clear! 

Hope I may have helped!

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last night we had great views of Jupiter here too, but am still struggling to figure how to get the best views

using my shortest EP (9mm) is was really clear but small (c x45 in my 100mm Newt). 2 dark bands were there if you looked

Barlowing the 9mm (to x90) and the subtle detail was gone. Jupiter was bigger but less clear. Maybe an even shorter EP has to go on the shopping list - or maybe a small reflector isnt up to the job?

You want to make sure you’re using the very best part of the scope's focal plane, otherwise you're going to lose detail. So check collimation in the day time and check it once again at night before observing.

It's also worth noting that if the seeing is bad it will create problems for planetary viewing in any telescope. The planet is often reduced to a boiling, wobbly mess and the same will happen if the winds are too strong. It's also a good idea to view Jupiter as high as possible on its orbital path near the ecliptic.

Good seeing conditions will override problems with light pollution and assuming collimation is spot on, you'll also find that on average, Jupiter doesn't need much more power than between 120x to 180x magnification. You'll even find that you can pick out a reasonable amount of detail at 100x.

By way of example, my small 3" frac can make out the north and south equatorial belts, the Great Red Spot, and the north and south polar regions. If you are sitting comfortably and stick with it, gradually, after 15 minutes or so of settled observing, Jupiter may reveal ever more subtler markings especially in the north and south temperate belts and larger markings in the north and south tropical zones. Of course, a larger aperture scope will offer better resolution but generally speaking, regardless of the aperture used the entire image of Jupiter at around 100x in the eyepiece won't really be much bigger than a large pea in the palm of your hand.

Here's a sketch I made this month using my 3" frac. The aim of the exercise wasn't to highlight the detail my eye actually captured but to give an idea of relative size and appearence of Jupiter, its visible moons and shadow transit at the eyepiece.  

post-21324-0-00042400-1420457770.jpg

I imagine your scope is something like a 4" f/5. Being of a short focal length it relies on very short focal length (FL) eyepieces to gain significant magnification. It follows, that these types of scopes are excellent for wide field, rich star field observing. A longer FL telescope narrows the field of view but allows one to use longer FL eyepieces, which in turn gives one more eye relief making planetary and lunar viewing a more comfortable possibility.

As you'll appreciate, magnification is equal to the telescope's FL divided by the EP's FL. So, if I wanted to enjoy Jupiter, for example, at around an average night's viewing of 100x to 160x in a 4" f/5, I'd need eyepieces between 5mm to 3mm.

There are potential problem of doing this. Firstly, the eye's optics. The exit pupil of a 5mm eyepiece in a f5 scope is 1mm. In consequence the view may appear fainter and more distorted. You will also become aware of any floaters in your own eye which can comprmise observations. Secondly, the telescope's optics may be far from perfect, so the more you magnify, the more you are likely to see its imperfections. Thirdly, as touched on above, the more you magnify the more you are likely to be magnifying the atmosphere's own turbulence. The upshot is that you help create an image of motion and distortion. Finally, collimation and the difference between the mirror and ambient temperature will also affect the image and anything not perfect will be augmented with magnification.

Needless to say, planetary observing requires a lot of patience and good moments of seeing. This feature of good seeing is often very transient with perhaps a few seconds of exceptional clarity over a minute or so. By throwing more magnification at the object without accessing the situation, decreases the likelihood of capturing those rarer moments of clarity.

If you were wanting to do planetary observations, typical recommendations for a 4" f/5 might include: i) a zoom eyepiece of decent quality of between 3-6mm ii) a decent Barlow which in effect helps double your EP collection whilst giving you the choice of buying a little longer FL eyepiece and retaining its longer eye relief; iii) a 60º field EP short focal length eyepiece (4mm) which due to its wider field will be easier to track your object; iv) an ortho of around these focal lengths (something which might be tricky to use); and finally, v) look into buying a slightly longer focal length scope. 

As mentioned, try to view Jupiter as close to the zenith or celestial meridian as possible and bear in mind that as a general rule of thumb the brightness of an object will decline as you up the magnification. On the other hand, you might be able to see more detail by upping the power, so there is a trade-off: will increasing magnification gain more detail even though I'm making the object fainter and in the worse cases, more blurry?

Playing around with this trade-off - dependent on the evening's seeing and sky conditions does make a difference. Even as little as 1mm increase or decrease in the eyepiece's focal length - about 10% to 15% difference of magnification - can be quite surprising. I don't own your scope, nor do I know what exactly is its focal length but you'll probably find that on a decent night your sweet spot is between 120x to 160x on viewing Jupiter and you will probably only be able to push 160x plus on the most excellent of nights.

You're very fortunate to own a scope reaching out across the universe some 675,000,000 kilometers and assuming the colimation is spot on, I'm sure with a little practice you will be able to see the Great Red Spot, those delicate reddish-brown belts, a darker, greyer hue to the Polar regions, and so on. You'll be able to trace the movement of the Jovian moons and observe their play of shadows over Jupiter in times of transit or of their eclipses by Jupiter's own shadow.

If you can, try to sit with Jupiter for a peaceful twenty or thirty minutes or so on your next observation session and ask yourself questions about what you are seeing, perhaps make a little sketch which also helps the eye to see more.

Good luck and let us know how you get along.

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I do not have 9 mm eyepiece. My biggest scope of you is my 70mm scope and its a f/4.3 . I was viewing the other night with my 6mm eyepiece. I also did the 4 mm eyepiece as well .. After I get it in focus , and it stops shaking , I love the view , I just wish it was bigger but I suppose if I can see some detail than I can benefit from filters.

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I've just had the best views of Jupiter with my 10 year old daughter, Using my Skywatcher Evostar 120 with an 8mm BST eyepiece and a 2" variable polarising filter screwed into the end of the diagonal with it set to its lowest (clearist) setting.

The rings of jupiter were so clear in comparison to viewing it direct and now chuffed to bits to have this filter on board. I then started looking at the moon, as it was the first time my daughter had ever viewed it through a scope and again we were amazed at the clarity and ease of viewing, using this polarised filter. all edges of the moon were so crisp and sharp, even managed to view the moon with my 2" BST 2x Barlow and the 8mm eyepiec that gave really beautiful images and pin point sharp in all areas.

Although the weather conditions here in Carmarthenshire aren't ideal with quite a few passing clouds, but when it clears the viewing tonight is amazing.

My daughter has just gone to bed freezing but amazed by the sighting of Jupiter and its 4 moons.

A beautiful evening not to be forgotten.

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