Install drivers, connect to QHY5L-ii two different ways
The drivers may change and these instructions may go out of date, so beware adjustments may be needed.
The QHY5L-ii and QHY5iii-174 are very sensitive video cameras that are well-suited to guiding and collimation with MetaGuide. Although they have small pixels, they are sensitive and have low read noise, making them good for guiding with a small guidescope or off-axis guider.
Example view of off-axis guiding with QHY on 8" SCT. Note the small (1.5") and well defined guidestar image.
Install Drivers
Go to the QHY download page and download the latest drivers for the camera. I used to recommend using broadcast mode, but with recent versions of MG since the 5.2.15 Beta, the frame rate is shown correctly and you can use the native driver without broadcast mode.
Download the system driver and the Native WDM driver.
Connect MetaGuide to the Camera
There are different ways to use the QHY camera in MG, but currently I recommend using the Native WDM driver.
When you start MG it should either connect directly to the camera, or list it as one of the cameras to choose from. If you don't see the camera listed make sure you have correctly installed both the system driver and the WDM driver - and anything related to DirectShow if available.
Note that MG never uses ASCOM for video or image download from cameras, so installing the ASCOM driver is not essential. But you will probably need to install it for other apps.
Guide with the Camera's ST4 Port
Unfortunately guiding through the ST4 port on guide cameras is no longer supported.
Troubleshooting
Make sure you actually have a display from the camera visible in MG, because even if the camera is not connected, MG will connect and give no error, but the screen will be gray or black. Make sure the camera is connected and the image shown in MG is changing when the view changes.
Be sure to adjust gain and exposure via the VidProps button on the main MG page. If the screen is white bring the gain and exposure down - and if it is dark bring them up. Try to avoid long exposures over 1/2 second or so that would lose the benefit of interactive video.
If there is still a problem try following the general troubleshooting advice on the MetaGuide Troubleshooting page.
Support
For support please read and join the forum at the main MetaGuide site
Guiding
Low latency guiding with video. Quick and accurate corrections for mid-range mounts.
Achieve tighter and rounder stars than with long guide exposures and standard centroid algorithms.
Let MG find and select faint guidestars as they come into view so you don't have to squint at the screen.
Collimation
Collimate using a star with the telescope aimed at the correct angle to the sky. Just center the coma dot on the star while the mount re-centers it. In better seeing you can use high power and collimate on the in-focus diffraction pattern.
Take an annotated and scaled image of your collimated star to show how well your star diffraction pattern matches theory.
Seeing measurement
Measure size of the star spot as it moves around over each 2-second interval, with live plots. Can be used as a dedicated seeing monitor with a telescope, or just to check seeing conditions
Drift alignment
Measure the dec. drift of the mount quickly so you can make rapid polar alignment adjustments to null out the drift.
Periodic error logging
Log periodic error in detailed formats for analysis in other tools. These measurements are taken every 0.5s with an accurate centroid, allowing high resolution studies of your mount behavior including gearbox and other noise. This may be the most important type of error for good guiding compared to the slower and more easily corrected terms.
GuideView mode
GuideView mode lets you watch the live guide corrections in video mode so you can see the small, fast motions of your mount that are the key to getting tight stars.