About
PHD2 (Push Here Dummy 2) is the leading open-source telescope guiding software used by astrophotographers and spectroscopists worldwide. It simplifies the complex task of guiding a mount to track a guide star with high precision, minimizing star trails and improving image quality during long exposures. For beginners, PHD2 includes a setup wizard that gets guiding running in just a few clicks, smart calibration that automatically adjusts for side-of-pier and pointing location, and proactive advisory messages to help improve guiding performance. Built-in tools for drift alignment and comet tracking make it a versatile tool for various observing goals. More experienced imagers benefit from multiple algorithm choices for each telescope axis, a Guiding Assistant for measuring mount performance, and extensive visualization tools for fine-tuning. PHD2 also supports automatic management of dark-frame libraries and bad-pixel maps, quick switching between multiple imaging configurations, and compatibility with adaptive optics and rotator devices. Developers and power users can leverage PHD2's automation interfaces to integrate it with third-party imaging applications, enabling fully automated imaging sessions. The software is cross-platform, actively maintained on GitHub, and supported by a dedicated community via the Open PHD Guiding Google Group. Its comprehensive built-in help file and downloadable manual make onboarding straightforward for users at all skill levels.
Key Features
- Setup Wizard for Beginners: Get guiding started in just a few mouse-clicks with an intuitive setup wizard and intelligent default settings.
- Smart Calibration: Automatically adjusts calibration for side-of-pier and pointing location, reducing manual intervention.
- Guiding Assistant: Measures mount performance and provides detailed metrics to help experienced users fine-tune their guiding parameters.
- Advanced Visualization Tools: Extensive graphs and displays for reviewing and fine-tuning guiding performance in real time.
- Automation & Third-Party Integration: Supports automation interfaces for integration with third-party imaging applications and workflows.
Use Cases
- Astrophotographers using a guide scope to precisely track targets during long-exposure deep-sky imaging sessions.
- Beginners setting up their first autoguiding system using the step-by-step setup wizard and intelligent defaults.
- Experienced imagers measuring and optimizing mount performance using the Guiding Assistant and multi-algorithm controls.
- Spectroscopists maintaining precise tracking of a target star throughout extended spectral data collection.
- Developers and power users automating end-to-end imaging workflows by integrating PHD2 with third-party software via its automation interface.
Pros
- Completely Free & Open Source: PHD2 is free to download and use with no licensing fees, and its source code is openly available on GitHub.
- Supports a Wide Range of Equipment: Compatible with a broad array of mounts, cameras, adaptive optics, and rotator devices used in amateur astronomy.
- Suitable for All Skill Levels: Beginner-friendly wizard and proactive suggestions coexist with powerful advanced tools for experienced astrophotographers.
- Active Community & Documentation: Backed by a dedicated Google Group community and a comprehensive built-in help file and PDF manual.
Cons
- Desktop-Only Application: PHD2 is a desktop application and does not offer a web or mobile interface, requiring local installation.
- Learning Curve for Advanced Features: While accessible to beginners, mastering the full range of guiding algorithms and assistant tools requires significant time and experience.
- Narrow Use Case: PHD2 is purpose-built for telescope autoguiding and is not applicable outside of astronomy or astrophotography contexts.
Frequently Asked Questions
What is PHD2 used for?
PHD2 is used to autoguide a telescope by tracking a guide star, which keeps the mount pointed precisely at a target during long-exposure deep-sky imaging or spectroscopy sessions.
Is PHD2 free to use?
Yes, PHD2 is completely free and open-source. It can be downloaded at no cost from the Open PHD Guiding website or GitHub repository.
What platforms does PHD2 support?
PHD2 is available for Windows, macOS, and Linux, making it accessible to a wide range of users regardless of their operating system.
Can PHD2 be integrated with other imaging software?
Yes, PHD2 provides automation interfaces that allow it to be controlled and integrated with third-party astrophotography applications for fully automated imaging sessions.
Where can I get help with PHD2?
PHD2 includes a built-in help file accessible from the Help menu. For community support, bug reports, and feature requests, users can post on the Open PHD Guiding Google Group.
