Eyepiece Help

[charmedkelly]

Hello Going To Purchase a 8" Dobsonian on sunday ( Looking Forward to it) well thats not what i need help with, im trying to find out what sort of lenses i need in my setup i have a few just wanted to know ur opinion on a good EP for Planetry and a good EP for DSO'S.

Thanks for all Your Help

Kelly

Oh hey what does anyone think of the 8" dob:hello2:

[John]

Hi Kelly,

An 8" dob is an excellent scope - you can see loads of stuff with it. I had a Skywatcher 8" dob and it was one of the best scopes I've ever owned - great at deep sky objects and planets - it was even pretty good a double stars as well !.

If you could say what eyepieces you have now we can suggest where the "gaps" are and how you could fill them.

John

[charmedkelly]

Ok, Yeah these are the EPs i have

SR 4mm

Plossl 6.3mm

ED 9.5mm

Celestron 10mm, Super 10mm

H 12.5mm

15mm

H 20mm

20mm Erecting Eyepiece

Super Wide Angle 25mm

Plossl 40mm

Revelation 32mm

2x Barlow

3x Barlow

Kelly:icon_salut:

[acey]

You've got everything you need!

2 or 3 good EPs should cover all your observing needs.

With my 8" f6 dob I found that Televue Plossls of 32, 15 and 8mm focal lengths covered all bases: the 32 for finding, the 15 for most DSO viewing, the 8mm for DSOs bright enough to stand the magnification, and for planets. Latterly I found myself rarely using the 32 as I could find objects easily enough with the 15 and a good map.

I got a barlow but hardly ever used it.

A Lumicon UHC filter (for nebulae) completed the set-up.

I've since moved up to a 12-inch and find an 11mm Plossl to be the eyepiece of choice for DSOs with that instrument. The crucial thing is really exit pupil: 1.5 - 2.5mm seems about right for detail in DSOs.

[Talitha]

Congrats on your upcoming scope purchase, Kelly!

[The Warthog]

Ok, Yeah these are the EPs i have

SR 4mm

Plossl 6.3mm

ED 9.5mm

Celestron 10mm, Super 10mm

H 12.5mm

15mm

H 20mm

20mm Erecting Eyepiece

Super Wide Angle 25mm

Plossl 40mm

Revelation 32mm

2x Barlow

3x Barlow

Kelly:icon_salut:

I would suggest you would get the most benefit out of the 6.3mm Plossl (190x), the 40mm (30x), The 9.5 (126x), the 15 (80x), the 25mm SWA (48x) and the 32mm (37.5x). Take those out to the field and see which ones you use most. Later, you can replace those lengths with better quality eps (not that there's anything very wrong with plossls.)

If you were buying new, I would have suggested something like 6, 10, 25 and 40. You do have all you need at present.

[ollypenrice]

Surely you already have enough focal lengths to sink a ship! Newtonians, in my experience, do like premium EPs which perform better off axis. I'd see which of your present EPs you use the most and maybe get a premium item in that length. The joy of the wider field EP with a Dob is not just more view but more view before you have to nudge it. Mind you, I know what I'd be looking at for deep sky - a 19mm TeleVue Panoptic.

Have you got some collimating device or other? Much more important than the quality of the EP.

Have fun,

Olly