Telescope: Newtonian 6 inch F5 Produced by NEWT version 3.0
Filename: C:\NEWTWIN\6IN_REDO.NWT
Specifications/Dimensions:
Unit of Measure -------------- inch
Primary Mirror Diameter ------ 6.0
Focal Length ----------------- 30.0
Focal Ratio ------------------ 5.0
Tube Inside Diameter --------- 7.2
Tube Thickness --------------- 0.25
Focuser Height --------------- 1.8
Focuser Inside Diameter ------ 1.25
Focuser Extra Travel --------- 0.3
Focuser Camera Travel -------- 0.0
Diagonal Minor Axis ---------- 1.52
Diagonal Offset -------------- 0.0760
100% Illumination Diameter --- 0.4116
75% Illumination Diameter ---- 1.0310
Front Aperture Diameter ------ 7.0205
Mirror Face to Focuser Hole -- 24.05
Focuser to Front End of Tube - 6.0
Mirror Face to Back of Tube -- 3.25
Tube Length ------------------ 33.3
Eyepieces:
Focal Length Power Exit Apparent True
(mm) Pupil Field Field
------------ ------ ------ -------- ---
40.0 19.05x 8.0 44.0 2.3
25.0 30.48x 5.0 50.0 1.6
16.0 47.63x 3.2 50.0 1.0
12.0 63.50x 2.4 50.0 0.8
9.5 80.21x 1.9 50.0 0.6
6.7 113.70x 1.34 50.0 0.4
5.0 152.40x 1.0 50.0 0.3
Performance:
The theoretical limiting magnitude for a 6 INCH objective is 12.7.
The obstruction of the primary surface area by the diagonal is 6%
which results in a reduction in light gathering ability.
The theoretical resolution (Dawes limit) for a 6 INCH objective is 0.76 arc seconds.
The obstruction of the diameter of the primary by the diagonal is 25%,
which affects image quality by increasing diffraction and lowering contrast.
Maximum useful power is about 300x (for 50x per inch of aperture).
Minimum useful power is about 21.8x (for a 7mm exit pupil).
Angular field of view for the 100% illuminated area is 0.7904 degrees.
The diameter of the field is 0.4116 inch.
Angular field of view for the 75% illuminated area is 1.98 degrees.
The diameter of the field is 1.031 inch.