Adds synthesized stars to the attached plate's image
Plate.SynthesizeStarfield(FWHM, LimitingMagnitude, LMFlux, LMExposureInterval)
The method syntax has these parts:
| Part | Description |
|---|---|
| FWHM (Double) | The full-width/half-max (arcseconds) of the stars to be added |
| LimitingMagnitude (Double) | The limiting magnitude for the generated starfield (assuming a noiseless base image) |
| LMFlux (Double) | Total flux for stars at the limiting magnitude (assuming a noiseless image) |
| LMExposureInterval (Double) | The exposure interval (seconds) at which limiting magnitude would be reached (assming a noiseless image) |
| Return (Nothing) | Does not return a value. |
The stars' intensities are proportional to the exposure interval, and will saturate/clip if over-exposed. The image must be first prepared with a pedestal and background noise using other means.
The generated stars will have Gaussian profiles with full-width/half-max as specified by the first parameter. The last three parameters establish the "depth" of the image for a particular exposure interval. LimitingMagnitude and its corresponding LMExposureInterval set the generated plate's "sensitivity" and sky-glow limits, however, this method does not simulate sky glow. The LMFlux parameter should be used in combination with noise you add to best simulate the detectability cutoff at limiting magnitude. For example, with a mean background noise of 350 ADU and background noise standard deviation of 20 ADU, a good starting place for the last three parameters is:
| Parameter | Starting Value |
|---|---|
| LimitingMagnitude | 19.0 |
| LMFlux | 450 |
| LMExposureInterval | 300 |