Planetary eyepieces in 10" f4.7

[Simon Dunsmore]

Hi Guys,

Sorry, back again to pick your brains!

I recently asked for advice about suggestions for a 10mm eyepiece to use in my 10" f4.7 dob. I think I've settled on the 52degree Explore Scientific. I would however like to try an eyepiece that would allow max magnification. I already have an Explore Scientific 3x barlow which effectively makes that 10 a 3.3 and give 363x mag on the scope. 

I really enjoy observing planets and the moon and for the moon especially wanted to squeeze as much mag as I can out of the scope. I was looking for a good 8mm eyepiece to use with e 3xbrlow to give a mag of 461. Id really like to hear any suggestions that you may have. I was considering the Pentax XF 8.5mm (presently on sale at Wex) budget of around £100.

Thanks for your help and suggestions

Simon

[rwilkey]

Hi Simon, I have never been successful at maxing out but if you want to try it then try it you must, with experience you will find the lower powers more useful even on solar system objects.  However, if you want to go down that road then the XF 8.5mm is a good eyepiece, but my opinion is that at that high magnification the image will be diminished and you will subsequently blame the eyepiece.  Jupiter, for example, is best at around 150x I have found, Saturn a bit more at 200x and so on.  Good luck in whatever you decide!

[John]

I've owned a Pentax XF 8.5mm. It's quite a nice eyepiece but it does have some distortions - pin cushion I think it's called ?

Interesting review here comparing the XF 8.5mm with a BST Starguider 8mm (the Paradigm is the branding they use in the USA for those) in a similar scope to yours:

https://www.cloudynights.com/articles/cat/user-reviews/review-of-at-paradigm-8mm-and-pentax-xf-85-mm-r2737

Using a 3x barlow will introduce it's own issues I think. I doubt that sort of magnification will get much use in all honesty - it doesn't in my 12 in Orion Optics dob.

 

[johninderby]

The Nagler 3-6 zoom would work very nicely but not exactly cheap. One zoom that compares favourably with an  ortho eyepiece.performance wise. 👍🏻

Edited August 25, 2020 by johninderby

[John]

27 minutes ago, johninderby said:

The Nagler 3-6 zoom would work very nicely but not exactly cheap. One zoom that compares favourably with an  ortho eyepiece.performance wise. 👍🏻

Zooms are great for high power observing - I've become quite a fan of using them now. My short fixed focal length eyepieces are feeling a little neglected I think 

[SiriusB]

10mm Baader classic ortho? (50 afov) 'bout £50, Zeiss design lens (though not Zeiss manufactured) according to Baader.

You did say for planetary, so only the centre sharpness,contrast etc etc matters.

Find my circle T orthos sharp very nearly to edge in f5 refractor,even though i think design specs for orthos are >= f6 ?

I have BCO 10mm,  it's not bad at all. IMO,good coatings, I may complete the set!~ though not sharp to edge as it's a 'wide'  ortho.

 

[John]

Interesting eyepieces the Baader Classic Orthos for a touch under £50 a punt. I reviewed them for the forum a while back: