Calcolatore Tolleranza Errore di Inseguimento
Calcola facilmente i risultati con il Calcolatore Tolleranza Errore di Inseguimento online gratuito.
Max Periodic Error
1.5400 arcsec
Max Periodic Error vs Worm Period
Formula
## Tracking Error Tolerance For unguided astrophotography, the mount's periodic error (PE) must be small enough that stars do not trail beyond the pixel scale. ### Formula **PE_max = pixel_scale * drift_pixels** - *pixel_scale* = arcsec/pixel from sensor and focal length - *drift_pixels* = acceptable pixel drift (typically 1 to 2 px) The drift rate limit is PE_max divided by the worm-gear period.
Esempio Risolto
0.77 arcsec/px scale, 2 px acceptable drift, 480 s worm period.
- 01PE_max = 0.77 * 2 = 1.54 arcsec
- 02Drift rate = 1.54 / 480 * 60 = 0.1925 arcsec/min
Domande Frequenti
What is periodic error?
PE is the back-and-forth tracking error caused by imperfections in the mount's worm gear. It repeats every worm cycle (typically 4 to 10 minutes).
How can I reduce PE?
Use periodic error correction (PEC), autoguiding, or a mount with a high-quality worm gear. Belt-driven mounts often have lower PE.
Is autoguiding always necessary?
For long focal lengths or multi-minute exposures, usually yes. At short focal lengths (under 200 mm) many mounts track well enough unguided.