Calculator Eyepiece Calculator Input Box Follow the steps below to see the eyepiece table. (1) Enter any 2 of the 3 parameters for your telescope You must enter 2 telescope parameters to see table results. More... The Calculator will use the first two parameters it finds in the boxes below and calculate the third. Parameter Examples: Focal Length: 2000 Aperture: 200 System will calculate f/#: 10 Focal Length: 2000 f/#: 10 System will calculate Aperture: 200 Aperture: 200 f/#: 10 System will calculate Focal Length: 2000 Input numbers with the following convention: Focal Length & Aperture: Do not use symbols to group digits together. (Good: 2032. Bad: 2,032 or 2.032) Focal Ratio (f/#): Use either one comma "," or one period "." symbol to indicate decimal point. (f/: 5.35 or 5,35 are the same) Input Examples: Focal Length: "1200", "1270", "2032", "2350", "2800" f/#: "5.5" = "5,5" f/#: "5 "= "5,0" = "5.0" = "5,000" = "5.000" Output numbers will use the period for decimal mark and comma for grouping. Output Example: 5000½ displays as 5,000.5 Focal Length mm in. Aperture mm in. Focal Ratio (f/#) ... or Recall a Stored Run Select Run Run Selected Delete All Delete Selected (2a) Choose telescope eyepiece preferences Does your telescope accept 2" eyepieces? Are you using a Tele Vue Paracorr? Limit to eyepieces that accept DIOPTRX astigmatism correctors? (2b) Limit to these eyepieces Current: Ethos Nagler Delos Panoptic DeLite Plössl Discontinued: Nagler (+zoom) Panoptic Wide Field Radian Plössl Click Stop Zoom Apollo (3) Enter optional run name and select table presentation order Run Name Sort True Field Magnification Design True Field: Listed from wide to narrow. Eps with same field sort higher mag first. Magnification: Listed from low to high. Eps with same mag sort wider field first. Design: Listed from narrow to wide field designs and zooms last. Note: Zooms sort based on low-power specification. (4) Calculate Results