3 mm EP

[Debostar]

Friends,

I have just ordered a 3mm EP to use on Saturn and other planets along with a light blue filter. I use a Barlow 2x and a 9 mm EP and I have a nice result although my saturn is still a bit small, it looks like a pea. Maybe with this 3mm EP, I should be able to get a larger image. The filter is to bring out some more contrast in the image, as I found using my moon filter with the present barlow 2x and 9mm does help to make certain banding faintly visible.

[John]

That will give you 217x which will be usable when observing conditions are good but sometimes you will get a sharper and more contrasty image (though smaller) at lower powers so don't be afraid to "back off" the power when conditions are not so good.

There is not a lot of contrast in the banding on Saturn to be honest - it's nothing like Jupiter in that respect.

[MjrTom]

Sounds like a plan :-)

I use a 3-6mm zoom eyepiece on my 80mm ED Refractor and it produces lovely images of Saturn.

With your scope and its slightly longer focal length of 650mm you should get a nice sized image of Saturn at 216x magnification, depending upon the seeing conditions at the time.

Which 3mm EP did you go for?

Not tried any filtering yet for visual observation but do have a Neodymium filter on order with FLO.

[E621Keith]

Although, I haven't tied mine on Saturn. My SV80s and 3mm Radian produced some wonderful result on Jupiter.

Recently I got lazy and just barlow my newly acquired 8-24mm zoom for Saturn.

What 3mm eyepiece did you ordered? You need to be careful with conventional designs, (e.g. plossl), as they have ridiculously short eye relief at such short focal length. On a budget, long eye relief designs such as Celestron X-cel, will be much more comfortable to use.

[Debostar]

this is a Omegon LE sieres 3mm EP which I think has a good eye relief (20mm).

Omegon Eyepiece LE Series 3mm 1,25"

Has anyone got this EP? What are your exepriences with it?

[russ]

That should be a good eyepiece. It's a clone of the William Optics SPL Planetary eyepiece and branded by a few other companies (Smart Astronomy for one) too. Nice and sharp, good contrast, nice 55deg field and plenty of eye relief. I only have experience with the William Optics 6mm & 12.5mm and the Smart Astronomy 18mm versions but all were very good.

[junior]

Is 217x mag a too much for your scope,

I have a skywatcher 130p and as soon as i get close to or over 200x i cant focus on saturn as well as if i was at 180x

[Debostar]

why is it like that? Does it not focus or is it too wobbly?

In any case I will have to see when I get it...

At a 9mm EP with a 2x Barlow, my image is good, although a bit small. I hope to increase the size using this 3mm EP. Of course I wouldn't use the Barlow with it.

[junior]

I cant remember the maths but i no the limit of my scope is around 200x mag because of its aperature size and focal length (im sure somone far wiser will correct me if i am wrong). If i use a 6mm eyepiece in a barlow lens. so a 3mm equivlent, then i get a much less sharp image than if i used a 4.5mm equivlent.

Also tracking becomes a major issue for me with mine being a manually tracked dob.

[NickK]

I bought a 3.5mm Baader Hyperion (68deg FOV) at SGL6. The image of Saturn is great through it - 675mm FL, f6.38 results in x192 magnification. It is noticeably dimmer than the 13mm EP but the idea in having it was for planets and Lunar.

Basically scope focal length / eyepiece focal length = magnification.

[MorningMajor]

Interesting to hear how you get one - might be pushing it a bit with the Barlow - lol

[Debostar]

I was not planning to use it with the barlow...but it seems a nice idea, but theoretically the EP length would become 1.5 mm then the magnification would be 433.3x which is overdoing it a bit...