Eyepiece

[Planet Guy]

Hi all

I have a Celestron 130 EQ Telescope and would like to see a bit more of the planets jupiter, saturn, and a bit more of Venus. At the moment, I'm using a 10mm Eyepiece, which gives me a magnification of 65x, but this doesn't bring out a whole lot of detail. I am looking at getting a 4mm eyepiece to get a bit more magnification. Would this be the highest I could go in magnification?

Also, how do you get the maximum usful magnification? Is there a general rule of thumb or a formula?

I want to get the best look at the planets and moon as I can, so I want to get the highest useful magnification I can, without the image turning into a fuzzy blur.

[Astro_Baby]

Telescopes generally have a maximum magnification of x2 for every millimeter of aperture. Hence a 130mm telesscope would have a maximum maginifaction of x260. Theres an alternative gauge of 50x magnification for every inch of aperture which gives slightly less.

In reality under UK skies around x200 is generally the max you can get up to for observing ( not sure if thats true for imgaing ). Generally I use a lot less than that.

Bear in mind also that basic Plossl eyepieces at 4mm will have a rather small bit of glass to look through and can be uncomfortable to use - thats probably why old time astronomers always have a squint .

You can use a Barlow lens to double the power of the exsiting eyepices by a factor of x2 so a 10mm with a Barlow will give you the equivalent of a 5mm eyepiece which works out at x130 magnifaction

(magnification is focal length of the scope - in your case 650mm divided by EP size - in this case 5mm).

I had a Sky-Watcher 130 which is roughly the same as yours and I found 5mm was about the maximum I could get out of it but found the view a bit wobbly.

Dont forget also that magnification is only half the issue, the more powerfully you magnify the fainter the image becomes.