Narrow and Medium-band Filters
from 4000 to 4499 Angstroms,
kept at the 3-meter

Central Wavelength	FWHM	Notes	Measured Wavelength/Widthd
4000	400	Thuan-Gunn V, Plot, Tablea	4033/339
4000	650	Plot, Table, Red leak starting about 7000A.Tape used as spacer between glass layers.
4023	25	Plot, Tablec; Labeled HED 7957, 2-inch round filter, very thick, doesn't fit in Kast filter wheel with standard filter holder.	4031/31
4043	60	Plot, Tableb, periphery degraded, central 1.5 cm ok.	4058/60
4060	70	Plot, Tableb, 1.5-inch round filter.	4103/72
4100	100	Plot, Tableb, 2-inch round filter.	4098/89
4200	250	Plot, Tableb	4234/254
4217	17	Plot, Tablec; labeled HED 0836 1847, 2-inch round, very thick, doesn't fit in Kast filter wheel with standard holder.	4225/27
4220	60	Plot, Tableb, very thick.	4222/58
4260	30	Plot, Tableb, degraded filter, wavelength redder than orginal specs.	4272/40
4260	80	Plot, Tableb, 1.5-inch round filter. Degraded coatings, wavelength redder than original specs.	4276/82
4265	65	Plot, Tableb, periphery degraded, central 2 cm ok.	4266/64
4300	60	Plot, Tableb, periphery degraded, central 3 cm ok.	4314/57
4315	30	Plot, Tableb	4320/27
4360	45	Plot, Tableb, very thick. Periphery degraded, only central 1 cm ok.	4374/45
4380	20	Plot, Tableb, Labeled ?old?, 2-inch round filter. Periphery degraded, only central 1 cm ok.	4391/17
4380	20	Plot, Tablec,Labeled HES 2348, 2-inch round filter, very thick. Won't fit in Kast filter wheel with standard holder.	4390/29
4450	60	Plot, Tableb	4456/62
4479	60	Plot, Tableb	4480/51

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^a Measured by M. Clendenin, 2012.
^b Measured by E. Gates, 2012.
^c Measured by B. Dupraw, 2012.
^d Gaussian fit to 2012 plot.