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Optics & framing

Field of ViewReducer & BarlowBack-focus SpacingPlate-solving ScaleMosaic Planning

Image quality

Resolution & SamplingSensor TiltDrizzle PlannerAutofocus Planning

Acquisition

Exposure & SNROptimal Sub-exposureIntegration PlannerFilter Exposure PlannerStar Saturation

Mount & guiding

Guiding RatioPolar AlignmentGuiding ExposureField Rotation

Sky & environment

Imaging WindowAtmospheric ExtinctionDew & Heater

Session planning

Calibration FramesStorage Volume
About this calculation: inputs, formula and confidence

How should I divide time between filters?

Allocate integration among three filters using priority and throughput.

Planning estimate

Formula

Ti = T(wi ÷ ηi) ÷ Σ(w ÷ η)

Lower-throughput or higher-priority channels receive more of the fixed time budget.

Where to find the inputs

  • Total timeProject priorities
  • Channel prioritiesFilter transmission curves
  • Relative transmissionsManufacturer data or measured throughput
  • Sub-exposureManufacturer data or measured throughput

Related

Exposure & SNR →Integration Planner →Atmospheric Extinction →

Filter exposure planner

Give every channel the time it needs.

Allocate a fixed session among three channels using scientific priority and relative transmission.

Purpose and method

What this calculator does

How should I divide time between filters? Allocate integration among three filters using priority and throughput.

In words: Lower-throughput or higher-priority channels receive more of the fixed time budget.

Change a value and the result updates immediately. Transmission is a useful first-order weighting term; target spectrum, sensor quantum efficiency, gradients and moonlight can justify a different allocation.

Working geometry

Channel time allocation

A fixed integration budget is divided among channels according to priority and relative transmission.

channel 1channel 2channel 3fixed time budget

Inputs

Channels and throughput

Unit: h
Unit: weight
Unit: weight
Unit: weight
Unit: %
Unit: %
Unit: %
Unit: s

Calculated now

Three-channel allocation

Channel 1 time
2.64 h
Channel 1 frames
32
Channel 2 time
3.39 h
Channel 2 frames
41
Channel 3 time
2.97 h
Channel 3 frames
36

Governing equation

Transmission-adjusted allocation
T=T×(w/η)/Σ(w/η)

In words: Each channel receives time in proportion to its requested weight divided by its fractional transmission.

Show the working

The calculator applies the equation above to the values currently entered, without rounding until this display.

Channel 1 time
2.64 h
Channel 1 frames
32
Channel 2 time
3.39 h
Channel 2 frames
41
Channel 3 time
2.97 h
Channel 3 frames
36

Transmission is a useful first-order weighting term; target spectrum, sensor quantum efficiency, gradients and moonlight can justify a different allocation.