Is there some sort of parfocal eyepiece list?

[Kevin Kretsch]

Some eyepiece lines are parfocal amongst themselves, and some are not, and some change over time, and some eyepieces of different brands are parfocal with each other and some are not. Is there a list what's parfocal with what? Is it plausible/possible to do one?

FYI, my 1998 Meade Series 4000 26mm Plossl is not parfocal with my new Chinese Meade series 4000 Plossls 20 mm and 15 mm (which had I known would have definitely influenced my purchase decision). But the new Meade Plossls *are* parfocal (or very close to ) with my 1990's Celestron Plossl and the Orion Sirius 32mm Plossl. 

Edited July 20, 2020 by Kevin Kretsch

[John]

There are so many eyepieces around I think this would be more or less impossible to compile and keep up to date.

Don Pensack's annually updated eyepiece specs list has over 1000 eyepieces on it and those are just the ones in current production:

https://www.cloudynights.com/topic/700069-2020-eyepieces-buyers-guide/

That list does not specify the position of the focal plane within each eyepiece. Some brands (eg: Tele Vue) are very specific about this, many are somewhat vaguer.