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Tele Vue Ethos 21mm Eyepiece

Tele Vue Ethos 21mm Eyepiece
Price:  £798.00(Inc. 20% VAT)

Product Code:  ETH-21.0
Brand:  TeleVue
Eyepiece Type:  Super-Wide Angle
Field of View:  100 degrees
Barrel Size:  2" Eyepiece



In stock, Shipped in 1-2 working days


Ethos 100° and 110° Apparent Field Eyepieces. 

The 21mm focal length completes the logical set of 21mm/13mm/8mm and nicely juxtaposes the 17mm/10mm/6mm combination. Each step within these two sets approaches a 3x field area gain. The 21mm's effective field stop diameter is 36.2mm, bringing its true field close to the 35mm Panoptic (38.7mm Field Stop diameter). Its true field is also larger than the 26mm Nagler with its 35mm effective field stop diameter. In an f/4 Dobsonian, the exit pupil is just 5.25mm using the 21mm Ethos instead of 8.75mm with a 35mm Panoptic, or 6.5mm with a 26mm Nagler.


  • Model #  -  ETH-21.0
  • Focal Length (mm)  -  21
  • Barrel Size (in.)  -  2"
  • Apparent Field of View (deg.)  -  100
  • Eye Relief (mm)  -  15
  • Weight (lb / oz)  -  2.25 / 36.0
  • Field Stop (mm)  -  36.2

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