1. 1 Atmospheric Limits to Precision William van Altena Yale University Basic Astrometric Methods Yale University July 18-22, 2005

2. 2 Point Spread Functions before the Atmosphere

3. 3 Diffraction Rings & the Secondary Mirror

4. 4 Encircled Energy

5. 5 Corrugated Wavefront

6. 6 Refraction in the Atmosphere

7. 7 Refraction as f( 

8. 8 Refraction - second order effects

9. 9 Effective Wavelength

10. 10 Transmission & Sensitivity Curves

11. 11 Spectral Energy Distributions

12. 12 Atmospheric Turbulence

13. 13 Temperature Fluctuations

14. 14 Degradation Function

15. 15 Degradation Function ~ Gaussian

16. 16 Turbulence Scale Length

17. 17 Zenith Distance

18. 18 Air Mass

19. 19 Image Motion - Lick Observatory Seeing ~1” ~2”

20. 20 The Observables

21. 21 How Adaptive Optics Works

22. 22 Natural Guide Stars

23. 23 Artificial Guide Stars

24. 24 Multi-Node Guide Stars

25. 25 WIYN Tip-Tilt Module First Order Adaptive Optics

26. 26 Tip-Tilt Corrections

27. 27 Image Motion - Two Cases

28. 28 Total Image Motion

29. 29 Relative Image Motion

30. 30

31. 31 Precision Limits due to Atmosphere