Ok i upgraded my ep`s

[wils07]

After some very good advice i decided to upgrade my ep`s from the stock skywatcher 10mm 25mm and 2 x barlow.

I decided to get a 9mm baader ortho ep and the celestron ultima 2x barlow.

So with my 130 f5 scope what combination would work best to try and see jupiter out of all 3 ep`s and my new barlow.

From what i read a barlow will reduce image quality so am i best using the 9mm on its own and say use the 25mm with the barlow? Or should the 9mm with the barlow still give me a good image. I guess its between 144x 72x and 52x but being new to all this what should i be using

Cheers Paul

[oldfruit]

To be honest you will only tell by actually looking through the eyepieces. Start with low magnification first and work your way up. Also allow for seeing conditions as no matter how good the eyepiece, if the seeing is bad then the image will appear bad.

[John]

Yes - the seeing conditions will determine which combinations are useful on any particular occasion - it can vary immensely so don't be too quick to blame your equipment if the views don't always come up to expectations.

The Baader and Ultima are nice items and should work well under good viewing conditions.

[brantuk]

Ideally the scope will be outside and cooled down to ambient temperature - takes about half an hour - to reduce the heat currents in the tube.

The seeing will be good - but that is down to atmosphere and your eyes. It can appear clear to the eye and you dont see the disturbance till you look through the ep.

The object will be high - too close to the horizon and it gets worse - a planet will appear to bubble, and whispy thin cloud will dim it considerably.

Keep an eye on the mirror periodically - you won't see dew build up till the image disappears lol. A hair drier on "warm" (not hot) blown round the tube sides will clear it - avoid blowing direct at the mirror cos it could crack.

Other than that - you've chosen some nice ep's to start building up a collection

[Rossco72]

On good nights you should be able to barlow the 9mm and I doubt you will notice too much deteriation of the image. But remember, the higher the magnification, the more the seeing affects what you see and the more rigid and robust your setup need to be to avoid vibrations.

Spend a few nights and try all the combinations, see what you like best. Sometimes a smaller sharp image lets you see more than a larger soft image at higher mags.

[pvaz]

I agree the items you have are very good. Only seeing, bad collimation and a warm scope can ruin the view.

[brantuk]

Collimation !! I knew I missed something lol

[FLO]

Hope this helps

Steve

[wils07]

just been out now as sky is clear and i got a image of it but nothing like above but just enough to see some gas clouds vaguely. It was better with the barlow and 9mm ep but how are conditions tonight in general to me it looks clear but is it really?

[John]

just been out now as sky is clear and i got a image of it but nothing like above but just enough to see some gas clouds vaguely. It was better with the barlow and 9mm ep but how are conditions tonight in general to me it looks clear but is it really?

You need to spend time observing to tease out the subtle details - a quick "look see" will show you the main belt and the moons but not much else. As you observe your eye will adjust to the brightness and you will gradually pick out more details, usually "on and off" as the seeing changes. I usually try and spend a good hour or two on Jupiter before I can say that I'm seeing all the the scope / conditions are allowing on any particular night. Also Jupiter rotates quite rapidly and it's fascinating to see features gradually moving across the disk as time goes by.

[wils07]

Im gonna give it another go tonight if all is well but i do have a question that i asked in another thread but has had no replys so im gonna ask it differently.

Can i put a polorizing filter on the bottom of my barlow as when i put in on my baader it it causes the ep not to sit flush with the barlow rim . Im not sure if the ep not sittin flush will be a problem so thats why im want to see if putting it on the bottom of the barlow would be ok

[great_bear]

From what i read a barlow will reduce image quality

When compared to an equivilent focal-length eyepiece, that's more superstition than anything else. Some attributes are helped by using a Barlow, and the best-corrected eyepieces (such as Pentax XWs) have a Barlow-style lens (called a Smyth lens) built-in - even in the focal lengths up to 20mm.

Naturally, a focal-length too short will reduce image quality - but that's true whether it's achieved using a Barlow or a dedicated eyepiece. It's a misunderstanding many newbies have.

With your Barlow and scope, the scope is the limiting factor, not the Barlow, and using that Barlow on the 9mm BGO you will get better results than many dedicated ~4mm eyepieces.