I have a 4.5" Newtonian Reflector and I took a look at Jupiter the other night.

I was able to get a reasonably sharp view of it and see a number of it's moons, but I was unable to see any surface details, it was pretty much just white glare.

I'm not sure if it's possible to distinguish any surface details with the telescope I have, so any advice on best setup would be useful.

I have a few accessories:

  • x2 barlow lense
  • 10mm eye piece
  • 25mm eye piece
  • 6mm eye piece
  • moon filter
  • color filters

Would anything else, other than a more powerful telescope, help me?

I was unsure if I might have an alignment issue that was causing this, but as I could make out the moons as sharp dots on the planetary plane, I assumed not.

Any advice would be welcomed.

  • 1
    $\begingroup$ Use either the Moon filter or yellow / green / blue color filters for Jupiter. And if you also have a polarizing filter (often found in filter sets) then you could try that too, or even two of them as a makeshift variable polarizer (by rotating them), or a combination of a few of the filters you have if they're of decent quality and not damaged. Make sure they're cleaned tho. Old filters can gather a patina of dust if not properly stored since they do tend to be made of electrostatic materials that attract dust. Use silk cloth / cotton pads and isopropyl alcohol if you need to do that. $\endgroup$
    – TildalWave
    Feb 21, 2015 at 2:21

1 Answer 1


Jupiter is a very bright object, so maybe the best procedure is to use your filters, they might help with the glare. However, I think you have either a case of low resolution or distortion. Generally, the larger the diameter of the telescope, the better is the resolution (more details here). Resolution defines how much detail you are able to resolve with the telescope.

Changing the eyepieces or using Barlow lenses can amplify the images, but it doesn't improve resolution (you'll just see a bigger blob - but still, it's cooler than just a small speck). There are also other things to check:

  • Was it windy? Too much wind can, usually, mean a turbulent atmosphere, and it hampers observations. Another way to check for turbulence is to look at stars with the naked eye: if they are twinkling too much, the atmosphere is very turbulent
  • Was Jupiter near the horizon? If so, maybe you should try observing it when it's higher in the sky. When looking near the horizon, light has to pass through a large column of air (a parameter known as airmass by astronomers), and it distorts images
  • Is the telescope well collimated? Poor collimation (mirror alignment) usually results in tail-like structures in sharp objects, almost like a comet. This is probably not the case if the scope is new
  • What is the quality of the optics? Some telescope manufacturers ship their products with very low-cost, low-quality optical components (eyepieces, filters etc.)

Also, if your objective is to observe mainly solar system objects, I suggest using a refractor telescope, they are wonderful for that. Additionally, this video by Phil Plait on Crash Course might help you and give invaluable information.


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