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Solanum
23-03-2007, 09:25 PM
I like to plan ahead..... and I'm wondering where to go in the future with eyepieces. Now I'm never going to be able to buy a load of Naglers, so don't bother suggesting it! :)

At the moment I have what I got with the 10" GSO dob (GSO 6, 9, 15 and 25 mm Plossls), plus a GSO 2x Barlow (not the ED unfortunately - I probably should have spent the extra I guess).

Obviously what I would want in the future is to maximise what I can see with my scope...... bearing in mind that I suspect my biggest interests will be the moon, the planets and DSOs.

1) I suspect that a wider angle/lower magnification eyepiece would be useful (for finding things if nothing else!), any suggestions as to size, whether I should go for 2 or 1.25" and what field of view I should look for (e.g. GSO Superview 2" 42mm)?

2) Secondly, I do find with the 6mm that my eyeball is almost touching the eyepiece to get the best view, therefore I imagine a 3mm of the same type will not be for me. So again, for higher magnifications, should I replace the 6mm with a better eyepiece of the same size or get something smaller of a different type? If so what type? Any advice on higher magnification eyepieces that are still comfortable to use?

3) would replacing the Barlow with a better quality ED one make a big difference or not?

I stress that I'm not about to get anything, but want to spend more time getting to know the scope and sky before buying anything else, but I would like to have an idea what to look out for, if only so that I can make sure I'm well and truly familiar with those aspects of my current eyepieces before going ahead. Also I do collimate my scope (well twice) and whilst I'm no doubt inexpert I would expect to further get the hang of it as I have more practice. Apologies for the length of this post!

MortonH
23-03-2007, 10:47 PM
For high power eyepieces that are comfortable to use, consider TeleVue Radians. They have 20mm of eye relief and are available in a number of focal lengths, from around 18mm down. My 6mm Radian is my favourite eyepiece. It'll give around 200x on your scope, which will be enough for good views of the planets.

Wide angle is more difficult. You can spend up to $900 on a fancy TeleVue 31mm Nagler, but not many can afford that! Best bet without breaking the bank might be a Plossl around 40mm. This will cost less than $200, whichever brand you choose.

Hope this helps.

Morton

casstony
23-03-2007, 11:29 PM
In 17mm and shorter focal lengths, with an eye on price but decent quality and comfort, check out the Orion Stratus and Burgess/TMB Planetary eyepieces. Frontier Optics have a 3 for 2 deal going at the moment on the Burgess eyepieces resulting in a price of $100 each. You won't need anything between 17mm and 30mm, but picking the decent quality/not too expensive 30mm wide angle eyepiece is tough - I can't think of one at the moment.

MortonH
24-03-2007, 12:06 AM
On the wide-angle side, Frontier Optics also has the Burgess TBM Paragon 40mm (2" fitting), which I just discovered has a very good review on Cloudy Nights. I'm thinking of getting one for myself as it's only $345.

Morton

wavelandscott
24-03-2007, 09:14 AM
You might try this question in the eyepiece forum...

I think you are right not to be in a big hurray to buy new...After you use what you have for a while you will have a good idea of what you like/dislike and then you can search for eyepieces that fit your viewing style.

Unfortunately, like most things in life the "best" are not cheap...but there are many "pretty good" choices that are more affordable.

I tend to have fewer really good eyepieces...I figure that the weakest part of the optical chain is what limits the view. In many cases for me it is now me and my knowledge and eyesight that is the weakest part of the optical chain.

Yes, they can be expensive but I think they will last me a lifetime!

casstony
24-03-2007, 09:20 AM
The 40mm Paragon does get excellent reviews but it will provide an exit pupil that is probably too big in an f/5 scope. The 30mm Paragon is due to be available soon, giving an exit pupil of 6mm which is useable even in a light polluted area.

ghsmith45
24-03-2007, 10:04 AM
I agree. The 6mm radian is a great eyepiece.
Geoff

davewaldo
25-03-2007, 02:49 PM
Hi Solanum,

I also have a 10" Dob with the same EPs you have. I was in a similar position as yourself a few months back, wondering how to expand/upgrade my EPs.

First off you mention that your barlow is not the ED type. Apparently this makes no difference as the ED and non-ED versions are the same! I now use an Orion Shorty Plus which is a nice upgrade for under $200

My first EP purchase was a Meade s4000 Ultrawide 14mm. This is not an easy EP to find second-hand but I think it is a great focal length EP for a first purchase. You might want to consider the Orion Status 13mm (or Baader Hyperion) as these are around $200. I was going to buy one of these when I found the Meade on ebay.

I liked the 14mm FL eyepiece as it was a good all-rounder. Once I find an object this is still my first choice EP to get a closer look. It is also great barlowed until you purchase a shorter FL EP. I noticed a big jump in sharpness and overall quality compared to the GSO plossls!

A decent low power EP for finding objects is hard to find unless you spend big bucks. I recently bought a Meade s5000 26mm Plossl which I find is good for finding objects and looking at wide views. Any bigger than 30mm is not recommended in our scopes as you may have issues with exit pupil size.

As for a shorter FL for planets etc. My next purchase will probably be an Orion Stratus (or Hyperion) 8mm. This is still a good EP for smaller clusters and nebulae but would be great barlowed to 4mm for planets.

Hope this helps.

Dave.

rockit
25-03-2007, 04:16 PM
Hi Solanum, this is not an easy answer because everyone see's differently(looking for different anomaly) The old rule, size of objective multiplied by mm of EP @ 254mm of diameter, a 12-14mm is your sweet spot giving 20x per inch of aperture, this would be an excelence size for a space walk ep if intending of going down that path. As for a 40mm I went for a GSO 2"kelner it has good flat field in a f5 12" showing good colour and contrast. For the moon its magnitude is what you will be trying to control the most. Don't laugh too loudly, but I made an ep from a pentax binocular optic and the 1.25 barlow the contrast and detail it draws out is excelent, and not eye ball scorching so it can be enjoyed for hours. An eye patch is useful if you don't already have one for your relaxed eye. Don't give up on those plossils try screwing a barlow element onto the end of them, this gives a 1.5 multiplier and its the only time I use a barlow element. My favorite star splitter is an old 10mm plossil with the barlow element on the end making a 6.6ep with good eye relief and 230x in my scope. Don't stress too much about a barlow IMO you would be better off with an ortho in your collection sheerly for the clearest viewing possible. My decisions were curtailed down by the fact I want a lunar and planetary scope to complement my DSO 12" Light Bridge. Experiment with what you have. Try to buy once, how many expensive ep's do you see being traded it is the ones that aren't there that you want. Good luck and when you buy it might clear up in Brizzy.

Solanum
27-03-2007, 08:09 PM
Thanks very much for all your replies (especially, davewaldo and rockit - a finbles fan?). It's given me plenty to think about!