Following are descriptions of the parameters and calculated values: |
GENERAL |
Parameters in edit boxes may be input, all others are calculated |
Aperture |
Aperture of your telescope in millimeters (mm),
typically 70-500 mm (INPUT) |
f/ratio |
f/ratio of your telescope, net of flatteners, focal reducers,
Barlows and focal extenders, eyepiece projection, and others, typically 2-50 (INPUT) |
Focal length |
Effective focal length of your telescope in millimeters (mm)
(CALCULATED) |
CCD pixel size |
CCD pixel size in micrometers (microns), typically 5-24
micrometers (INPUT) |
Wavelength |
Wavelength of light in nanometers (nm), typically 550 nm for the average of
visible light, in the range 400-700 nm for visible light, or in the range 300-800 nm
for UV-IR (INPUT). Some typical wavelengths:
Visible light - 550 nm (average)
Red filter - 640 nm (average)
Green filter - 530 nm (average)
Blue filter - 440 nm (average)
H-alpha - 656 nm
H-beta - 486 nm
O-III - 501 nm
S-II - 672 nm
N-II - 658 nm
|
Diffraction limit |
Diffraction limit of your telescope in arc-seconds, at the given
wavelength (CALCULATED) |
Seeing |
Astronomical seeing in arc-seconds, typically 0.4-6.0
arc-seconds (INPUT) |
Total seeing |
Total seeing in arc-seconds, combined effects of diffraction limit and
astronomical seeing (CALCULATED) |
Imaging seeing |
Seeing experienced during imaging in arc-seconds, combined effects of
total seeing and defocus (CALCULATED) |
Focus tolerance |
Percentage tolerance from best case of total seeing, typically 1-20
percent |
NCFZ |
New Critical Focus Zone in micrometers (microns), typically 10-1000
micrometers |
Focuser travel |
Focuser travel to reach perfect focus in micrometers (microns),
typically 5-500 micrometers |
GoldFocus error |
Focus error as measured by GoldFocus analysis software in pixels,
typically 0.1-10.0 pixels |