mag for jupiter

[wolfspirit]

Hi

I have just got my new scope (skywatcher 130p(650mm long))

with the eye-pieces supplied (10mm, 25mm & a X 2 barrow lens) with these lenses jupiter is realy small you can't

make out the bands.

Does anyone know what eye-piece i need to clearly

see the bands

many thanks

Ryan

[kniclander]

hmm - you certainly should see the bands with the 10mm e/p. Are you focussing it really really carefully? Try also looking when it is highest in the sky.

If that doesn't work, could the collimation be out:icon_scratch:

[irishbloke]

Also make sure scope is cooled properly as air-curents will mess with the view. With Jupiter being now quite low by darkness You'll be looking through a lot of atmosphere which will also limit clarity.

I had the same scope as you and loved it. The view of the double cluster through a 32mm plossl was brill! Hope you enjoy it.

Brian

[Naz]

It can take sometime to "see" through a scope, with Jupiter being low in the sky as the above posters have said, the bands can sometimes appear fainter than you expect, but with the scope cooled and the 10mm EP you should see the two main equatorial bands.

[wolfspirit]

i did focus it carefully i only got it today and i have never

used a reflecter befor when it was out of focus it got really big &

looked like cotton wool with a grey sentre i dont know whether

it's the collimation or not how do i tell

[wolfspirit]

naz

it looks like a dot

its not that they are faint

i can just make out one very very very! small red line

thanks

ryan

[John]

i did focus it carefully i only got it today and i have never

used a reflecter befor when it was out of focus it got really big &

looked like cotton wool with a grey sentre i dont know whether

it's the collimation or not how do i tell

Sounds like the scope was not in focus - even if the collimation is off a bit you should get something that looks a bit like this:

http://www.cloudynights.com/ubbthreads/attachments/2611170-Jupiter%208-03-08.jpg

John

[kniclander]

if you want to look into collimation check out astro_baby's guide to collimation which you can find if you search this forum. also "Andy's shot glass" gives a pretty good explanation too (google it). But I agree that it sounds more like a focussing issue - the collimation would have to be pretty badly out not to see jupiter's bands.

[wolfspirit]

thanks very much

ryan

p.s

i moved the focus weel all the way and the best

i got was nothing compared to to the one on the link

[wolfspirit]

i am confused could the fact that the focusing was out change

the size even thow it looked clear

[kniclander]

if the focussing was out it would look bigger.

i didn't understand you earlier post about it looking like a dot and seeing one very faint red line. With the 10mm e/p (65x mag) it would be a little disc, about 3-4mm across (I would guess)

[Capricorn]

60x or 65x should manage to just show 2 bands, I used that mag on a small refractor recently.

Best way to check your focus is simply to use the moons and get them sharp (small pinpricks). The Jupiter should also be in focus.

If you cannot get the moons in focus then it will be collimation or cool down.

Should also have said that it is small anyway.

[Dazraz]

Sounds like the scope was not in focus - even if the collimation is off a bit you should get something that looks a bit like this:

http://www.cloudynights.com/ubbthreads/attachments/2611170-Jupiter%208-03-08.jpg

John

Thats how i see it through a 8" Dob !

[John]

Thats how i see it through a 8" Dob !

Because of it's low altitude there have been nights when I've not seen this much with my 12" dob but also better nights when I've seen all that and more with my 4" refractor. There are so many variables affecting what you can see at a given time - it's all too easy to blame your equipment or your eyes when it's actually the conditions causing the issues.

Wolfspirit:

You could have just been looking on a night of bad seeing. Give it another try - try and get sharp focus (ie: pinpoint moons and a reasonably sharp edge to the planets disk) with your lowest power eyepiece (the 25mm on it's own) and give your scope a good 30-60 mins to cool down fully before trying the 10mm and then adding the barlow only when you are happy with the view at lower powers - to be honest some of the barlows I've seen supplied with scopes are very poor quality (ie: not even achromatic) and will add distortion to the view.

John

[Dazraz]

Because of it's low altitude there have been nights when I've not seen this much with my 12" dob but also better nights when I've seen all that and more with my 4" refractor. There are so many variables affecting what you can see at a given time - it's all too easy to blame your equipment or your eyes when it's actually the conditions causing the issues.

Wolfspirit:

You could have just been looking on a night of bad seeing. Give it another try - try and get sharp focus (ie: pinpoint moons and a reasonably sharp edge to the planets disk) with your lowest power eyepiece (the 25mm on it's own) and give your scope a good 30-60 mins to cool down fully before trying the 10mm and then adding the barlow only when you are happy with the view at lower powers - to be honest some of the barlows I've seen supplied with scopes are very poor quality (ie: not even achromatic) and will add distortion to the view.

John

Totally agree !

[astropete]

are you just using the 10mm e/p? and not with the 2x barlow?

with my 127mm scope and using just a 20mm e/p jupiters size is about 4mm across and i can just make out the two main belts, on a lower powered e/p 25mm i can see the 4 main moons and jupiter in the same field of view.

to check your scope try tomorrow in day time to focus upon a tree or a house roof, and if you can and all is well your scope is ok. as said above focus slowly untill you get a pin sharp image, dont rush, it takes time. the planets and stars even the moon will be there for ages yet, so practice your focusing and good luck.

[wolfspirit]

thanks

i will try again as soon as the clouds clear up

Ryan

[mike.brightmore]

I suppose the first thing is to be sure that you are looking at Jupiter (sorry but you never know esp. when you describe it as a dot). My advice would be to start with the moon - can you see the craters and other details clearly using varying degrees of magnification. If that's ok then Jupiter shouldn't be a problem. Try looking at it with binoculars first - you should just about be able to pick out its moons.

[Wobbly Bob]

I was going to suggest a bright star (Vega) but Mike solution should be Ideal with the Moon very prominent at the moment.

[denniscook]

Hi Ryan,

I'm a newbie too with the same scope as you and only had it for four days. Last night I saw Jupiter very clearly at x10 with the x2 Barlow as supplied with the kit. I could only see the two bands on occasion but just stick at it, they will magically appear and disappear with the seeing conditions. Jupiter's moons were very clear, early on saw three moons with Ganymede and Callisto occulting and later saw all four. Brilliant!

Regards,

Dennis

[vegas]

I would also add that averted vision can help pick out the bands, as does practice. I was quite dubious at first when started with the hobby that my eyes would just 'train' themselves, though low and behold they do. Somewhere the info of what you've seen is retained and each time I go back to something like Jupiter, as I know what I'm expecting to see, it seems a little easier each time to notice those faint bands.

p.s. I have the same scope as you.

[denniscook]

Hi Vegas,

Can you confirm what mag you observe jupiter with? I notice that you have the same scope but also have a 6mm EP. Have you used the 6mm on jupiter and with the Barlow? I am thinking the 6mm could be my next buy.

[vegas]

Hi,

I have tried with the 6mm but it's nigh on impossible to focus, whether that's related to how low Jupiter is at the mo, or whether it just pushes magnification too high I'm not sure.

I use the 10mm mostly, again with the Barlow x2 I find focussing an issue.

I would hold of to be honest with buying a 6mm, only because I now regret parting with £30 for an EP i rarely use. I think my money would have been better spent on upgrading my 10mm or 25mm as they are the stock SW ones and alot of people replace them quite quickly.

[pvaz]

On some nights the seeing is so bad that even with the 25mm it's impossible to get a sharp image of Jupiter. Then on the day after it's clear even on my 10mm with the Barlow.

That said it's better to have a 6mm for planetary observation then to use the 10mm + Barlow. I always notice I loose a lot of detail when using the Barlow. my view with my 10mm is always better then the 20mm + Barlow, even though the 20mm is a better EP with wider field and displays sharp images to almost the full extent of the FOV.

[wolfspirit]

Thanks again for all your replies and help. I looked at jupiter again tonight with the 10mm and x2 Barlow - it was a great view. It was about 3 mm across and could make out 3 faint bands and 3 of the 4 Galelaon moons.Does anybody know which moon is which?

Thanks

Ryan

p.s. can anyone tell me the difference between a ploss ep and a normal ep?