1. Observational techniques meeting #8

2. Filter systems

3. Johnson system

4. SDSS system (Gunn filters)

5. IR filters

6. Narrow-band filters

7. More… >215 systems …

8. Spectrographs

9. Dispersive elements: prism High throughput; low resolution; wavelength-dependant dispersion R=t dn/dλ

10. Dispersive elements: diffraction grating R = m L k

11. Dispersive elements:grism

12. Dispersive elements: reflection grating

13. Cross-dispersed echelle

14. Slitless spectroscopy

15. Spectrograph

16. Multiplexing Multislit masks Fiber spectrographs

17. LAMOST 3.5-4.9m mirror 4000 fibers 16 spectrographs Xinglong station

18. End