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Getting started

  • Installation
    • Requirements
    • Install from source (recommended)
    • Using a conda environment
    • Verify the installation
    • Running the test suite
    • Building the documentation locally
  • Quick start
    • The mental model
    • 1. Build a scene
    • 2. Create a simulation for a sensor
    • 3. Compute signal-to-noise
    • 4. Invert: exposure time for a target SNR
    • 5. Change parameters and recompute
    • 6. Check saturation
    • 7. Simulate a detector image and plot it
    • Where to go next

User guide

  • User guide
    • Concepts and architecture
      • The three building blocks
      • Constructing a simulation
      • Inspecting and updating parameters
      • Count rates and the electron budget
      • Accessor properties
    • Scenes, sources, and backgrounds
      • Building a scene
      • Magnitude systems
      • Stellar and galaxy templates
      • Parametric source spectra
      • Rebuilding a parametric spectrum with update
      • Backgrounds
      • Working with scene elements directly
    • Signal-to-noise and exposure time
      • Image-based SNR (the default)
      • Exposure time for a target SNR
      • Multiple reads (n_reads)
      • The analytic Airy SNR
    • PSFs and image simulation
      • PSF models
      • Automatic PSF selection by focus level
      • Simulating an image
      • Grid size and oversampling
      • Telescope jitter
    • Saturation
      • The peak pixel
      • The saturation flag
      • Saturation in the image and SNR paths
    • Plotting
      • The house style
      • The four plots
      • Two ways to call them
      • Convenience methods on SimulatedImage
      • Return values and embedding

Tutorials

  • Tutorials
    • Getting started with the WCC ETC
      • Imports
      • 1. Build a scene
      • 2. Build a simulation for a sensor + filter
      • 3. Compute the SNR
      • 4. Inspect and update parameters
      • 5. Visualize the source spectrum and filter bandpass
      • Where to go next
      • Summary
    • Saturation flag demo
      • Build a scene and simulation
      • Sensor ADC properties
      • Peak-pixel fraction
      • Single-exposure check
      • Sweep exposure time
      • Effect of source brightness
      • Sensor comparison: 16-bit vs 12-bit
    • from_sensorfilter — auto-selecting the PSF from the filter focus level
      • Imports and scene setup
      • 1. In-focus filter (zwo:r) → AiryPSF
      • 2. Defocused filters (zwo:r+1, zwo:bb2) → DefocusPSF
      • 3. Visualizing the auto-selected PSFs
      • 4. get_image_snr uses _default_psf automatically
      • 5. Guards
      • Summary
    • 04 — PSF simulator and PSF-aware SNR
      • Setup
      • 1. PSF gallery
      • 2. Full image simulation
      • 3. Effect of pointing jitter
      • 4. PSF-aware SNR cross-check (rendered Airy vs analytic)
      • 5. Defocus SNR penalty (same aperture)
      • 6. Aperture optimization
      • Summary
    • n_reads and exposure-time-for-SNR inverses
      • Setup
      • 1. Analytic round-trip
      • 2. PSF-aware round-trip
      • 3. SNR vs n_reads at fixed exposure time
      • 4. Required time for a fixed SNR vs n_reads
      • 5. Per-frame saturation flip
      • Summary
    • Parametric source spectra
      • 1. Blackbody – Planck shape and Wien’s law
      • 2. Flat – constant F_nu vs constant F_lambda
      • 3. Power law – F_lambda proportional to lambda^alpha
      • 4. Emission lines – absolute integrated flux
      • 5. Driving the ETC – SNR vs magnitude (Pogson scaling)
      • 6. update() rebuilds the spectrum (type is locked)
      • 7. Normalization bandpass – Johnson + SDSS
      • Summary

Reference

  • API reference
    • Top-level public API
    • Modules
      • Simulation
      • Scenes (wcc_etc.scene)
      • Sensor
      • Telescope
      • PSF and image simulation (wcc_etc.psfsim)
      • Plotting (wcc_etc.plotting)
      • Astrophysics helpers (wcc_etc.astro)
      • I/O and configuration (wcc_etc.io)
  • Configuration and sensors
    • Sensor strings
    • The configuration files
    • Example — the Sony detector config
    • Example — the telescope config
    • Overriding configuration at runtime
    • Reading configs programmatically
  • Changelog
    • v0.1.0
wcc-etc
  • Overview: module code

All modules for which code is available

  • wcc_etc.astro
  • wcc_etc.io
  • wcc_etc.plotting
  • wcc_etc.psfsim
  • wcc_etc.scene
  • wcc_etc.sensor
  • wcc_etc.simulation
  • wcc_etc.telescope

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