Pentax XW

[25585]

22 hours ago, Louis D said:

The closest I can think of is the 30mm ES-100 if you have a 3" focuser and diagonal:

Sorry to play trumps but http://apm-telescopes-englisch.shopgate.com/item/323434373238

 

[Louis D]

Getting off topic, but here's some more bigguns.

Siebert Elite 80 in use at Mt. Wilson:

100mm Masuyama Kellner at the Orion USA store that is loaned out to local observatories:

Leitz 30mm 88 degree in two versions.

The normal sized 30mm Leitz 88 on the left weighs 820g or 28.9 oz and the diameter is about 77mm.

The "extra plan" on the right is 1410g or 49.6 oz and the diameter is about 80mm.  It certainly has been surpassed recently, but I find it mostly interesting because it's the only one of which is known to exist.

Zeiss manufactured a 160 mm  80° AFOV Huygens eyepiece (8 inch barrel, 185 mm fieldstop, weight: 9 lbs) :

And of course this from the Televue homepage for years: