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Newbie79
27-08-2009, 11:37 AM
Hi,

I am going to buy some more eyepieces (been using the two that came with my skywatcher scope but need more variety)

Just wondering what type I should get. I have been looking around and see that the price varies from fairly cheap right up to "Sweetheart can I put a second mortgage on the house"

I have been looking at the $50-90 mark for each eyepiece.

Have been looking at the Meade and Skywatcher brands. What are people's opinions on these brands. Are there any others around that might be worth considering?

Thanks for your help

Matt

erick
27-08-2009, 11:45 AM
Do tell us a little more. What is the scope - aperture and f ratio? What are the current eyepieces? What do you think of those - like, don't like? What do you want to spend your time looking at - faint small galaxies, the Moon, the Planets, open star clusters, nebulae, everything! ?

Newbie79
27-08-2009, 12:12 PM
My scope is a 10 inch Sky Watcher Dob. Focal Length =1200mm. The eyepieces that I have are the 10mm and 25mm that came with it. As for what I think of them I haven't looked through anything else to be able to compare (There isn't a club near where I live so looking through other peoples is not an option unfortunately)


I do really enjoy looking at anything (Planets, Nebula and galaxy, open star clusters)

Thanks Matt

erick
27-08-2009, 01:38 PM
OK, it's an f4.7 so more prone to coma at the edges of the field of view. Some people hate that. When I stated, seeing anything was a bonus so I could live with this. And that is what you will have to live with with cheaper eyepieces. Your $50-90 limit is a challenge, probably impossible in new eyepieces (but the second-hand market can deliver as new for 70-80% of new price)

I forgot to ask if you need to wear glasses to observe? That influences the eye relief that an eyepiece needs to have. Too little eye relief (such as you get in, say, a 6mm plossl design) and you cannot get your eye close enough.

Here are some thoughts:-

Get a wide-angle, low magnification eyepiece. There is a generic 30mm, 2", 80 deg Apparent Field of View (AFOV) eyepiece available from many places. Andrews ( www.andrewscom.com.au ) sell this one:-

"ANDREWS 2" 80° 30mm ultra-wide apparent field eyepiece."

for $99 (that's gone up lately!) At f4.7, you will have some significant coma in the outer field, but it will be more enjoyable than your 26mm due to wider field.
Also get a 2x barlow lens. This one from Andrews is made by GSO and can be used with 2" and 1.25" eyepieces.

"ED 2x magnification, 2" (with 1.25" adaptor), FMC, 2 el., achromatic"

Andrews sell it for $79. This allows you to have less eyepieces but still have a range of magnifications that you can use. So you now have 30mm and the equivalent of 15mm.

Now, you need a higher magnification eyepiece, but with your barlow available, you don't have to go too low in focal length. Maybe a 12-15mm will be sufficient. If you could get a Vixen LV 12mm, that would be nice - but locally they sell for $199 new. On the second-hand market, you should be able to pick up one for $100 or less. These are nice glass and have good eye relief. Your view would be better than the 30mm from above in the barlow.

Alternatively, try a plossl design. Stick with your 10mm plossl for a while, by itself and in the barlow. (Probably in the barlow will be "pushing it" for most seeing conditions.) If you find you are OK with the AFOV (49-50deg in a plossl), maybe a better quality plossl is what you want. I see Bintel

https://www.bintelshop.com.au/welcome.htm

has Televue plossls reduced - 15mm and 11mm each for $115. Perhaps the 11mm used by itself and barlowed for the Moon, Jupiter and Saturn on nights of good seeing.

wavelandscott
28-08-2009, 10:50 AM
How long have you had your scope and how often have you been able to us it?

At the end of the day in my opinion you only need 3 eyepieces...hitting High, Medium and Low Magnifications for your scope...

What eyepieces came with the scope?

Having said that I reckon you will be hard pressed to find a lot of choice in your price range...I might suggest that you save up a while and consider revising your budget upward. For a little bit more money I think you can get some pretty reasonable eyepieces that will work okay in your scope.