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Hubble Space Telescope
WFPC2 ETC for Point Sources - v4.0

For details select the colored text. General info. and help.


Stellar Spectrum:

Magnitude:    Spectral type:


Power Law:

Flux: (erg cm-2 s-1 Hz-1)

Freq./Wave.: (Hz/Ang.)     Sp. Index:


Emission Line:

Line Flux: (erg cm-2 s-1)

Line:    : (units)

Reddening (color excess): E(B-V):

Sky Background:

Rough estimate: Low Average High


Detailed Estimate Based on Object Location:

Right Ascension: H  M  S
(Equinox 2000)

Declination: D  '  ''
(e.g. "23 55 31.1" or "-00 05 34.3", omit + signs)

Sun Angle: D (usually 90 degrees)    Low Sky?


User Specified V Magnitude for Sky:   mag arcsec-2

Instrument Configuration:

Configuration: WFC PC    A/D Gain: 7 e-/ DN 14 e-/ DN


If using LRF Filter give desired Central Wavelength:  Angstroms

Data Analysis Method:

Optimal PSF Weighting:

Object Location on Pixel:   Pixel Center    Pixel Corner

Simple Aperture Photometry: Aperture radius: pixels


Enter either S/N or Exposure Time.

Signal to Noise: Exposure Time: Sec.

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