Quote:
Originally Posted by wavelandscott
You might consider attending a viewing night (or organizing one) and then see if anyone would let you try out their eyepieces (of brands previously mentioned) before you buy them.
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This is the best advice. Get out to a star party and look through some different eyepieces.
First question. Do you require eyeglasses when observing? If yes then consider eyepieces with 20mm eye relief.
Otherwise one could easily recommend Tele Vue 21mm, 13mm & 8mm Ethos eyepieces for your telescope for a first and final set maybe complementing with 6mm later, but if you don't like or have difficulty with 100 deg. fields then this is money wasted.
One could also easily recommend 31mm, 22mm, 13mm & 9mm Nagler eyepieces. This combination was (and still is) very popular before the Ethos came on the scene.
Its nice (but not essential) to have eyepieces with the same apparent field of view for then the true field of view changes in proportion to the magnification.
As for the Paracorr, this is a very personal choice. I can see coma at f6.4 and have used a Paracorr for a very nice 'clean' image but does the coma bother me and do I use the Paracorr each observing session; no in fact usually not at f6.4. Same applies to my f5.5 telescope. At f5 too you will likely find coma not to be bothersome but again it is a personal decision.
I'm not familiar with the eyepieces you mention but I doubt they are responsible for the rainbow of colours and all of the obove mentioned eyepieces will produce a similar effect since I believe other factors are at play.
Is your telescope collimated?
Is your telescope acclimatised to ambient temperature (usually cooled).
What was the altitude of the object you were observing? If low in the sky atmospheric refraction will give you colour fringing on bright objects.
Tele Vue eyepieces are designed and tested for fast telescopes and the only aberration you will see is primary mirror coma which is linear from the centre outward and which the Paracorr will negate. However you will find the coma seen is small or faint depending on magnification and unless it really bothers you can put the money towards another eyepiece. Note some planetary observers will still use a Paracorr to give the largest possible coma free image on axis.
See
http://televue.com/engine/TV3b_page.asp?ID=2
and
http://televue.com/engine/TV3b_page.asp?id=154
and
http://televue.com/engine/TV3b_page.asp?id=214
and
http://televue.com/engine/TV3b_page....212&plain=TRUE
and
http://www.televue.com/engine/TV3b_p...id=61&Tab=_con
See if you can get to a star party and have a look. You will find some eyepiece you like and some that you don't for whatever reason.
Whatever you choose, enjoy!