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Originally Posted by JJDOBBER79
I have recently read numerous posts on different forums by people praising the TV plossls and claiming that it is the same glass and coatings as used in their premium EP’s. If this is correct , then it would be fair to say that all we are paying extra money for is a wider field, and seeing as this is something that I obviously don’t value at the moment, I feel I may be wasting my money.
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In the case of Tele Vue, the extra money is for a highly corrected wider field so much so that in a Newtonian you actually see pure coma (a function of the primary mirror) and no other aberration and then all you need to eliminate the coma is a Paracorr if it bothers you for say f5 and under. There are many other branded wide field eyepieces on the market and some have considerable field curvature and off axis astigmatism. Surprisingly a Paracorr can improve the view with some of these eyepieces but in the end it comes down to what you're prepared to accept as far as off axis aberrations go.
My take is this; if I want an 80 deg field I want it all available to me not just 50 degrees of it otherwise I too would use a Plossl. Also when an eyepiece has significant field curvature then there is a significant part of the field that is out of focus. Any faint galaxy for example would be invisible in the outer part of the field.
Note highly corrected eyepieces such as Tele Vue perform well on any telescope. However some less well corrected eyepieces perform well on telescopes with longer focal ratios.
Your idea of using Plossls is fine but note the eye relief extends out further when using a Barlow with an eyepiece and eye placement and vignetting become an issue in say 30mm and over. A Powermate would eliminate this problem.
Buying and selling all the time is a personal choice. Some people do it all the time for various reasons and sometimes end up buying the same eyepiece back. It depends on what you want or need at the time but you should also think of what you may need in the future. You don't want to have to pay twice for an eyepiece you already had once.