Please need help

[Katash707]

What mm eyepiece is best to observe Jupiter with with a 200/1200 reflector only just starting and not sure on this thanks

[MarsG76]

Hello,

The answer to your question depends on seeing, so during below average seeing most you could use at 200mm aperture and 1200mm focal length telescope 10mm or longer... Of course that will mean that your magnification will be modest... But you will still see the equatorial cloud bands and the Galilean moons.

At average conditions 6mm eyepiece would be a good ball park but during good to excellent seeing you can use a 3mm eyepiece. Now if the seeing is good, you will see detail in the cloud bands and Jupiter's disc will be quite big in the FOV.

[ronin]

Jupiter is OK from a low 60x upwards, could be a bit small and bright in your scope, so lets say 80x to 100x, that means a 15mm or 12mm for your scope.

Next is that later in the year Saturn makes an appearance, that is smaller and further away, so you will want about 120x to 150x for that.

I tend to keep magnification down and hope that this produces a better quality image even if smaller, so keep that in mind.

So Saturn would mean 10mm or 8mm.

Do you want say an eyepiece for Jupiter, if so then try a 12mm, or want to have one for both in which case try a 10mm.

Could jump in at the 8mm mark but if it fails you are sort of back at square one, an 8mm should work fine I will say and would expect no problems. Just a bit cautious when it is someone else's equipment.

As I have the BST's they come in 12mm and 8mm form, which may be an option or you.

Get the 12mm now for Jupiter and 100x and in April consider the 8mm for Saturn.

By then you will have some idea of what you prefer.

[Stu]

What mm eyepiece is best to observe Jupiter with with a 200/1200 reflector only just starting and not sure on this thanks

There is no right or wrong answer to this. It really depends upon conditions and the position of the planet.

Assuming good seeing and Jupiter well placed then x180 is often a good maximum to use, so around a 6 or 7mm eyepiece. An 8mm will give you x150 which is very useable.

To me, there are four golden rules to get right for planetary observation

Collimation

Cooling

Seeing conditions

Patience

The first two you can do something about or ensure your scope is properly cooled and collimated.

The third one is just a matter of observing on different nights to get a window of good seeing.

Lastly, spend time at the eyepiece. I don't mean seconds or a few minutes, I mean half an hour or more. During this time you will catch the moments of good and excellent seeing which reveal the detail you want to view. Your eye and brain work together and build this into a picture of more detail. The longer you look, the more you see. It's not unknown for planetary observers to spend hours looking at Jupiter or Mars.

[laudropb]

Under normal seeing conditions I use a 12mm eyepiece with my 200p. At a magnification of 100x you will get a fairly small image, but spending some time observing will allow you to make out some details, including the GRS. When seeing is very good you can get away with an 8mm eyepiece or higher. But this does happen often.

[glynnlondon]

Good advice above and definitely worth spending time on Jupiter , those moments of clarity really make it worthwhile.

As for me I use my 7mm Astro hutech most often for high power when seeing allows.

[Katash707]

Thanks for the help a lot of good advice to set me on my way thank you