ASCOM Camera driver for Panasonic Lumix Cameras

August 13, 2026 · View on GitHub

Purpose

This driver presents Lumix cameras as ASCOM cameras so they can be used by astro photo software like APT, NINA or SharpCap. It can talk to the camera two ways:

  • Wi-Fi - the Lumix http remote control protocol. The camera believes that it is connected to the Panasonic ImageApp.
  • USB - the Panasonic Lumix USB (PTP) SDK, over the cable. Much faster than Wi-Fi and there is no wireless session to drop.

See Connection modes for what each one supports.

The driver was tested with the G80, GH4 and GH5s but should work with all Wifi Lumix.

Your camera needs one of the two transports. Either built-in Wi-Fi with "Remote Shooting" (the ImageApp protocol), or USB tethering the Panasonic SDK recognises. Bodies that predate both - the 2009 GH1 is the usual example - cannot be driven at all: no Wi-Fi to connect to, and LUMIX Tether does not support them either. A sensor size appearing in the table below only means the driver knows that body's geometry; it does not imply the body can be reached.

16MP sensor was the prototype. Now it is possible to work with a range of sensor sizes such as:

  • 10M (GH5s)
  • 12MP (GH1 - geometry only, see the note above)
  • 16MP (GH4, G80, etc.)
  • 20MP (GH5, G9, etc.)
  • Full Frame also like S1 and S1-R (but this hase not been tested)

Notes:

  1. ASCOM still exposes no "liveView" or video mode, so it cannot be handed to your imaging software. The driver now provides its own Live View window, opened from the setup dialog, on both Wi-Fi and USB - useful for framing and focusing. See Live view. Mostly this driver sets the ISO (i.e. Gain), ShutterSpeed, Capture (Start and Abort) and GetImageArray methods along with other needed methods for ASCOM.
  2. All settings are stored in the ASCOM Proflie Explorer
  3. Trace log is stored in default ASCOM location
  4. Presumably could also work with the full frame S series from Panasonic since it shares the same http protocol. The different format of the sensor should be handled but i have no way of testing it. (this is a call to get loaned an S1 to test!)

Connection modes

Pick the transport at the top of the setup dialog. The driver detects a cabled camera and preselects USB when it finds one, because the body cannot be on Wi-Fi and USB at the same time.

Wi-FiUSB (Standard)USB Extended (Tether)
needscamera on the same network, in "Remote Shooting"USB cable, camera in PC modeas USB, plus Panasonic LUMIX Tether installed
transfer formatsJPG, RAW, ThumbRAWRAW, JPG
exposuresdiscrete speeds + bulbdiscrete speedsdiscrete speeds and bulb of any length, including over 60 s
live viewyes (MJPEG over UDP, VGA or QVGA)yesyes
speed~8-15 s per RAW frame (direct link)~3-6 s per frame~3-6 s per frame
32-bit buildyesnono

USB Extended is the interesting one: it uses the fuller SDK that ships with Panasonic's LUMIX Tether application, which is what makes exposures longer than 60 seconds possible. The Tether application itself is never launched - only its SDK is used, and it is not redistributed with this driver. Install LUMIX Tether from Panasonic if you want that mode.

USB is 64-bit only. The Lumix USB SDK is x64, so the 32-bit driver is Wi-Fi only.

Usage

A Video tutorial is available

First install the driver. Of course you need to have ASCOM platform installed on your target windows PC.
To connect your PC to the camera:

  1. First on the camera (similar to what is needed with the Panasonic ImageApp)

    1. Prerequisites
      1. set it to "M"
      2. make sure there is an SD card too. (this exception is not handled yet)
      3. best if camera is set to manual focus too. (indeed if the camera tries to capture and cannot find a focus it will not capture. that exception is not handlded yet)
    2. Connect to a wifi network where you will also connect your PC
    3. Camera then waits for an app to connect
    4. Proceed to steps on the PC. If you are too slow to do these steps on the PC the camera will timeout and leave the waiting to connect status.

  2. On the PC

    1. launch the Imaging software (e.g. APT, NINA)
    2. choose the Lumix Ascom from the chooser window and click properties
    3. the driver will look for the Lumix camera on the local wifi network and connect to it (the camera should say "under remote control")


    4. IP address is populated by the driver after its discovery.
    5. Check that the correct resolution for your camera is discovered
    4. set the ISO, Speed and TransferFormat (JPG, Thumb or Raw): read below for details
    8. Hit ok.
    10. The Astro Software then gets data from the driver like the pixel pitch but does not get the temperature� in your Astro Software you can then set the Bulb seconds of the capture the gain etc. 11. You can now shoot!
    12. in APT you can then also (and more importantly) use the image received by the driver to perform platesolving.
    13. Live view is not passed to your imaging software - ASCOM has no interface for it - but the driver has its own preview window. See Live view below.

Connecting over USB

  1. On the camera: set the USB mode to PC / tethered shooting, and plug the cable in. Turn Wi-Fi off - the body will not do both.
  2. On the PC: open the driver's Properties as above. The Connection dropdown at the top should already show USB (Standard) or USB Extended (Tether), and the status line underneath names the camera it found (e.g. USB cam: DC-GH5S Tether: found).
  3. Choose the transfer format (RAW, or RAW/JPG in Extended) and press OK.
  4. Connect from your imaging software as usual. No IP address and no network discovery are involved.

Live view

Press Live View... in the setup dialog. It works on both transports and shows the frame size and rate so you can tell what you are getting.

  • Over Wi-Fi the camera streams MJPEG over UDP. You can pick VGA (640x480) or QVGA (320x240) - QVGA halves the bandwidth on a weak link. Changing size restarts the stream, so expect a short black gap.
  • Over USB the frames come from the SDK.
  • The Wi-Fi stream arrives on an inbound UDP port, so Windows Firewall must allow your imaging application. If you get no frames, that is the first thing to check.

The driver sets the camera's speed, ISO and transfer format, pulls the image (RAW or JPG) to the PC, and exposes it to the calling program as a 16-bit RGB image array regardless of the transfer format. The driver forces the camera to store RAW and Fine JPG.

Decoding happens in memory on both transports. A RAW frame goes straight from the transfer buffer to LibRaw (libraw_open_buffer) and never touches the disk. A JPG is decoded from the buffer by the .NET imaging stack; the one intermediate it still needs - a TIFF that ImageArray reads back - is written to the system temp area under a unique name and deleted as soon as ImageArray has been read. There is no user-configurable temp folder any more; earlier versions had one for a file-based download path that no longer exists.

RAW is the higher-quality choice but the file is much larger and slower to transfer, and over Wi-Fi the camera streams it slowly. Earlier versions aborted a slow RAW at a fixed 30 s and passed on a truncated frame; the Wi-Fi download now resumes until the whole file has arrived (with a byte-range resume if the camera stalls mid-stream), and the content browse is hardened against the camera's DLNA quirks - so a RAW-over-Wi-Fi capture completes reliably. Expect roughly 8-15 s per RAW frame on a solid direct link, more on a weak link or through a Wi-Fi repeater.

Because the readout is sequential with shooting, that time is time you are not exposing - a 1-minute sub plus a 15 s readout is 15 s of lost sky. Hence the smaller, faster JPG transfer, which is still perfectly usable for plate-solving. In every case the camera keeps the RAW (or RAW+JPG) on its SD card, and your imaging software still gets a FITS frame from the driver.

I added a "thumb" transfer mode which takes a large thumbnail of the image (1440x1080) in order to further reduce the transfer size. After exptensive tests it seems that platesolving is working well with the Thumb format too as the resolution is changed based on the THumb size and the pixelpitch is changed in the driver so to help in that process.

There used to be an issue with the latest RW2 14-bit formats that DCraw did not handle. The driver uses LibRaw instead, installed next to the driver DLL.

Exposure timing: bulb vs the camera's shutter list

The camera has a fixed list of discrete shutter speeds (1/4000 … 1 s), plus bulb. How a requested exposure is realised depends on the transport:

  • Wi-Fi always uses bulb - the driver opens the shutter, waits the requested time, and closes it. Any duration works, but very short exposures are imprecise because the open/close HTTP round-trips dominate.
  • USB Standard can only fire the camera's discrete shutter speeds, so a sub-second request is snapped to the nearest one.
  • USB Extended (LUMIX Tether SDK) can do either, and exposures over 1 s always use bulb.

For sub-second exposures on USB Extended the setup dialog offers a choice:

  • Camera list (default) - snap to the nearest real shutter speed. Accurate, but discrete: 0.00079 s becomes 1/1000 s.
  • Bulb - hold the shutter open for the exact requested time. No snapping, at the cost of precision on very short exposures.

The control is greyed out (with a tooltip) on Wi-Fi and USB Standard, where the transport already dictates the behaviour.

Whichever mode is used, LastExposureDuration reports the exposure actually taken (the snapped 1/1000, not the requested 0.00079). Clients that drive exposure from that value - a flat-field wizard hunting a target ADU, say - then see a consistent exposure/brightness relationship even when several requested times snap to the same shutter speed.

LibRaw version, and replacing it yourself

shipped with the driver
64-bit (libraw.dll)0.22.2
32-bit (libraw32.dll)0.19.5 - libraw.org no longer publishes an official Win32 binary, so the 32-bit build stays on the last one available. Build from source if you need a newer one.

The driver logs the LibRaw version it loaded in its ASCOM trace at connect (LibRaw 0.22.2-Release), so a "my RAW will not decode" question can be answered from the log.

You can drop in a newer LibRaw yourself - replace libraw.dll in the driver's folder. This is safe: the driver only calls LibRaw's flat C API through opaque handles and marshals none of its structs, so there is no layout to break between versions. A newer LibRaw is the usual fix for a recent camera body whose RAW the driver cannot read - newer than the sensor table in cameras.json, which only carries geometry.

Installation

You need the ASCOM platform 6.2 or later.

  • 64-bit (recommended) - run ASCOM.Lumix.Camera Setup.exe. Wi-Fi and USB.
  • 32-bit - run ASCOM.Lumix.Camera Setup32.exe. Wi-Fi only: the Lumix USB SDK is 64-bit, so a 32-bit host cannot load it. Only use this if your imaging software is 32-bit and you do not need USB.

Both install to the same place, so installing one replaces the other.

For USB Extended (bulb over 60 s) also install Panasonic's LUMIX Tether. The driver uses its SDK where it is installed; nothing from Tether is redistributed here.

Implements: ASCOM Camera interface version: 2.0 Author: robert hasson robert_hasson@yahoo.com this is freeware. no support, no liability whatsoever, use at your own risk, etc...

Adding a camera / resolution

The known-camera and sensor-resolution tables live in cameras.json, installed next to the driver DLL. To add a body or fix a resolution, edit that file — no rebuild required:

{
  "resolutions": [
    { "class": "24.2", "rawX": 6026, "rawY": 4017, "jpgX": 6000, "jpgY": 4000 }
  ],
  "models": { "S5M2": "24.2", "S9": "24.2" }
}

Each models entry maps the camera's reported model string to a resolutions class. The driver ships an embedded copy as a fallback, so it still works if the file is missing.

Upgrading does not overwrite this file, so your additions survive. To take a newer shipped table instead, delete cameras.json and re-run the installer.

Note this file only describes sensor geometry. If the driver cannot decode a recent body's RAW at all, that is LibRaw's table, not this one - see LibRaw version.

Credits to

ASCOM library : https://ascom-standards.org/

DCRaw: https://www.cybercom.net/~dcoffin/dcraw/

LibRaw: https://www.libraw.org/

not used anymore: NDCRaw : https://github.com/AerisG222/NDCRaw MedallionScript: https://github.com/madelson/MedallionShell

the lumix Wifi interface protocol is heavily discussed here: https://www.personal-view.com/talks/discussion/6703/control-your-gh3-from-a-web-browser-now-with-video-/p1

License

Copyright (c) 2019 < robert hasson robert_hasson@yahoo.com> This work is licensed under the Creative Commons Attribution-No Derivative Works 3.0 License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nd/3.0/ or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.