How to Download Astrophotography Photos From AsiAir

After an imaging session on AsiAir, your photos — lights, darks, flats, and biases — are sitting on the controller's internal storage. AsiAir doesn't push files to your computer automatically, so you need to get them off yourself. Depending on how many files you have and how often you image, this can be a quick task or a major bottleneck.

This guide covers every approach, from plugging in a cable to fully automated download and organization.

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Method 1: USB-C Direct Connection

The most straightforward approach — plug in a cable and copy files.

1. Connect a USB-C cable from the AsiAir to your computer.
2. The AsiAir appears as a USB mass storage device.
3. On macOS: it mounts automatically in Finder under /Volumes/.
4. On Windows: it appears as a new drive letter in File Explorer.
5. Navigate to the Autorun/ directory and copy the folders you need — Light/, Dark/, Flat/, Bias/, or all of them.
6. Disconnect when done.

Downsides:

• Requires physical access to the AsiAir — inconvenient if it's mounted on the telescope in an observatory or remote setup.
• You may need to power off the AsiAir, interrupting any ongoing session.
• All file sorting (matching calibration frames to lights by filter, exposure, and temperature) is on you.

Method 2: Network Share (SMB)

AsiAir exposes its storage as an SMB network share. You can browse and copy files from any computer on the same network while the AsiAir is powered on.

On macOS

1. Make sure your Mac is on the same network as the AsiAir (the AsiAir's own hotspot or your home Wi-Fi if using station mode).
2. In Finder, press Cmd+K (Go > Connect to Server).
3. Enter: smb://asiair.local/ASIAIR (or smb://asiair/ASIAIR).
4. Click Connect and select Guest — no password needed.
5. Browse the directory structure and copy what you need.

On Windows

1. Open File Explorer.
2. In the address bar, type \\asiair\ASIAIR and press Enter.
3. If prompted for credentials, leave username and password empty (guest access).
4. Copy the files.

On Linux

# Mount the share
sudo mkdir -p /mnt/asiair
sudo mount -t cifs //asiair/ASIAIR /mnt/asiair -o guest,vers=2.0

# Copy all frames
cp -r /mnt/asiair/Autorun/* ~/astrophotos/

# Unmount when done
sudo umount /mnt/asiair

AsiAir File Structure

AsiAir organizes all captured frames under the /Autorun/ directory:

ASIAIR/
  Autorun/
    Light/
      M42_Light_300s_Ha_0001.fits
      M42_Light_300s_Ha_0002.fits
      ...
    Flat/
      Flat_5.2s_Ha_0001.fits
      ...
    Dark/
      Dark_300s_0001.fits
      ...
    Bias/
      Bias_0.001s_0001.fits
      ...

Each filename encodes the frame type, exposure time, filter, and sequence number.

Downsides of Manual Network Transfer

• Slow over Wi-Fi — a full session of 200+ FITS files at 30–60 MB each can take a long time.
• No automatic matching — you need to manually pair darks (by exposure + temperature), flats (by filter), and biases with your lights.
• No session tracking — you don't know which files are new, which have already been copied, or which belong to which session.
• SMB conflict on macOS — mounting the AsiAir share in Finder while other software accesses it via SMB can cause connection issues.

Method 3: Scripted Automation

If you're comfortable with the command line, scripts can automate the file transfer.

rsync on Linux/macOS

#!/bin/bash
# sync-asiair.sh — Sync all frames from AsiAir

ASIAIR_HOST="asiair.local"
SHARE_NAME="ASIAIR"
MOUNT_POINT="/tmp/asiair_mount"
DEST_DIR="$HOME/astrophotos/$(date +%Y-%m-%d)"

# Mount
mkdir -p "$MOUNT_POINT"
sudo mount -t cifs "//$ASIAIR_HOST/$SHARE_NAME" "$MOUNT_POINT" -o guest,vers=2.0,ro

# Copy all frame types (rsync skips already-transferred files)
mkdir -p "$DEST_DIR"
rsync -av "$MOUNT_POINT/Autorun/" "$DEST_DIR/"

echo "Synced to $DEST_DIR"

# Unmount
sudo umount "$MOUNT_POINT"

Run this after each session, or schedule it via cron:

# Runs daily at 6 AM
0 6 * * * /path/to/sync-asiair.sh >> /var/log/sync-asiair.log 2>&1

PowerShell on Windows

$date = Get-Date -Format "yyyy-MM-dd"
$dest = "$HOME\astrophotos\$date"

net use Z: \\asiair\ASIAIR /user:guest ""
New-Item -ItemType Directory -Force -Path $dest
Copy-Item "Z:\Autorun\*" -Destination $dest -Recurse
net use Z: /delete

Write-Host "Synced to $dest"

Limitations

Scripts improve on manual copying, but they still have significant gaps:

• No calibration matching — you still need to manually figure out which darks, flats, and biases go with which lights.
• No session awareness — scripts don't know about imaging sessions, targets, or equipment.
• No status tracking — no record of what's been downloaded, what's new, or what failed.
• No stacking integration — after downloading, you still need to organize files and set up your stacking software manually.

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Automating Everything With AstroMate

AstroMate was built to solve the entire workflow — from the moment a frame is captured on your AsiAir to a stacked result ready for post-processing. No manual file management, no scripts, no sorting.

Automatic Discovery and Download

AstroMate connects directly to the AsiAir's SMB share using TCP/SMB2 — no OS-level mount needed (avoiding the macOS Finder conflict). It scans for new files every few seconds and handles everything automatically:

1. Detects new frames within seconds of capture — lights, darks, flats, and biases.
2. Parses each filename to extract frame type, object name, filter, exposure time, and sequence number.
3. Groups frames into sessions by target, telescope, and capture timing.
4. Downloads in the background with progress tracking and automatic retry on dropped connections.
5. Organizes locally into a clean structure: {Telescope}/{Object}/{Date}/{FrameType}/{Filter}/.

There's nothing to configure — as long as AstroMate runs on the same network as your AsiAir, it handles everything.

Intelligent Calibration Matching

When you create a stack, AstroMate shows all available calibration frames and recommends the best match:

• Darks are matched by exposure time and sensor temperature (within a configurable tolerance).
• Flats are matched by filter and telescope.
• Biases are matched by session.

Each pairing is a single click. If calibration frames are missing, you see a clear warning before stacking.

Integrated Stacking Pipeline

When you click "Run Stack":

1. Any calibration frames that haven't been downloaded yet are automatically queued.
2. Master calibration frames (darks, flats, biases) are generated via Siril.
3. Light frames are calibrated, registered, and stacked automatically.
4. The result is ready for post-processing — no manual steps in between.

The entire pipeline runs in the background with real-time progress logging. You go from "photos on the AsiAir" to "stacked image" with a single button.

Why It's Worth Automating

For a typical narrowband session — say 100 Ha lights, 50 OIII lights, 30 darks, 30 flats per filter, and 50 biases — you're looking at 300+ files. Manually downloading, sorting, and matching those files takes 30–60 minutes of tedious work. AstroMate does it in the background while you sleep.

If you're spending more time managing files than processing images, give AstroMate a try — it handles discovery, download, organization, calibration matching, and stacking so you can focus on what matters: capturing the night sky.