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Phil,
The maximum field of view of a 1.25" eyepiece is approximated with a 32mm plossl having an AFOV of about 52 deg. There is a formula, you multiply the AFOV by the focal length of the eyepiece and for a 1.25" eyepiece the maximum value is about 1650, for a 2" eyepiece it is about 2800. ie 32 x 52 = 1664.
The 24mm TV Panoptic also approaches the maximum FOV for a 1.25" 24 x 68 = 1632.
Al Nagler from Televue recommends a 32mm Plossl or 24mm Panoptic as the best low power eyepiece for use in an 8" SCT. In your scope a 32mm Plossl will give a TFOV of 50' or .83 of a degree. This isn't too bad when you consider your scope is not designed as a rich field scope. If you went that way the best eyepiece would be the 30mm Orion Ultrascopic for about $200 from Sirius Optics in Brisbane or the 30mm Celestron Ultima. These eyepieces are almost identical and offer superb image quality.
If you want to go the 2" route there is no reason you can't use a 2" 30mm eyepiece. Something like the 30mm GSO Superview (65 deg AFOV) would give you a TFOV of just on 1 deg. But a $200 diagonal and a 2" eyepiece is a big shellout when you could buy a far better quality 1.25" eyepiece for a slightly smaller TFOV.
If it was me I would be going with a 1.25" 30mm Plossl and be happy with what I have.
The SCT is a wonderful all round telescope it does a very good job of most things telescope, an excellent job of no things telescope, but wide fields of view is one of the areas the SCT is not seen at its best. Use your LX90 for the things it does best. If you want a Rich Field Scope buy one designed for that specific purpose like the Orion ST80. This scope would give a TFOV of almost 4 degrees with a 30mm 52 deg AFOV plossl. Horses for courses.
CS- John B
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