Rasid

A modular application for stacking and processing astronomical images in real time. Computation runs on the GPU.

Download Rasid

  • Windows

    Windows 10 or later, x64. A GPU with Vulkan 1.2.
    Unpack the archive and run Rasid.exe.

  • macOS

    macOS 15 or later, Apple Silicon (arm64). Intel Macs are not supported.
    Unpack the archive and open Rasid.app.

The workflow is an arbitrary chain of actions, in any set and any order. Input can be a series of frames, for stacking, or a single frame when only processing is needed.

Features

File formats

  • FITS, TIFF, PNG, JPEG, SER.
  • DSLR RAW — read-only.

Stacking

  • DSO Stacker: lights, optional flats and darks.
  • Registration — star detection, frame alignment, quality scores, adjustable rejection thresholds.
  • Integration — kappa-sigma clipping and photometric normalization.
  • RCD debayer; 1× and 2× drizzle; stack WCS from the Register reference frame.
  • HDR Compose — merge up to three linear exposures with star alignment.

Processing

  • On the linear frame: background subtraction, photometric color calibration (PCC); GraXpert neural models for background, noise, and deconvolution.
  • Stretch (MTF, asinh, GHS); color correction; multi-scale sharpening; star / starless split via StarNet; crop.
  • Export — PNG, JPEG, TIFF, FITS; WCS on FITS from frame astrometry (when available).

Astrometry

  • Astrometry for the current image: plate-solve, FWHM of main stars, and labels for deep-sky objects.
  • Plate-solve uses the built-in solver and the local ASTAP D05 database; PCC queries Gaia DR3 for the field.

ASTAP, StarNet, and GraXpert are not part of the application — they are installed from Settings. Photometric color calibration and catalog overlays require an internet connection (Gaia, SIMBAD).

Getting started

The window is split into two main areas. At the bottom are the actions (nodes) of the current project, the processing steps. At the top is the view with the current image. The display mode is changed from the bar: Linear, sRGB, or Auto.

Nodes are created from the right-click menu. They can be moved, deleted, and cloned. A node can have several inputs and outputs, depending on what it does. An input of one node connects to an output of another — that sets the processing order. A click on an input or output makes it active — the view shows the frame from that point in the chain. A node can be turned off; its output is then the same as its input.

A detailed description of the nodes is in the corresponding section. Nodes for images and series can also be created by dragging a file or a folder into the application window. To save to disk, use the Export button on the bottom bar: pick format and bit depth in the dialog, then the file path. The file is the frame at the current preview point (pipeline pixels).

A simple stacking and processing example