UIST has two 24-slot filter wheels which contain filters for both imaging and for blocking the spectroscopy grisms. The MKO consortium filter set is installed where possible (see the discussion of new JHK standards for example). Click on the filter name to see an image of the profile (where available). Text files are also available giving transmission profiles for some of the filters, contact Sandy Leggett. The table below lists the filter wheels’ population. 

1 March 2003 – 1 March 2004

Wheel 1

Posn	Filter	50% Cut on	50% Cut off
1	Open	–	–
2	Blank	–	–
3	Black blank	–	–
4	blank	–	–
5	Hartmann mask	–	–
6	Blank	–	–
7	Kshort	2.028	2.290
8	Klong	2.019	2.434
9	1.57(cont) [MK]	1.561	1.583
10	FeII[MK]	1.630	1.656
11	2.248(S1)	2.234	2.269
12	2.248 MK	2.235	2.270
13	2.122(S1)	2.106	2.124
14	2.122 MK	2.103	2.134
15	BrG MK	2.150	2.182
16	CH4_s	1.550	1.657
17	CH4_l	1.617	1.730
18	2.27cont[98]	2.257	2.291
19	2.42CO	2.413	2.436
20	L'[MK]	3.428	4.108
21	M'[MK]	4.572	4.800
22	blank	—	—
23	PK50 2mm	—	2.7
24	Blank	–	–

Wheel 2c

Posn	Filter	50% Cut on	50% Cut off
1	Open	–	–
2	9.95mm circ aper	–	–
3	blank	1.49	1.78
4	B2 blocker	1.43	2.60
5	J-spectral	0.96	1.71
6	HK-spectral	1.58	3.38
7	H-spectral	1.27	2.50
8	KL-spectral	2.11	3.13
9	L-spectral	2.56	4.61
10	J[MK]	1.17	1.33
11	H[MK]	1.49	1.78
12	K[MK]	2.03	2.37
13	3.4nbL	3.379	3.451
14	3.5mbL	3.383	3.594
15	3.6nbLp	3.560	3.625
16	3.99(cont)	3.964	4.016
17	BrA	4.025	4.080
18	PAH MK	3.264	3.318
19	3.28″Dust”	3.250	3.305
20	3.0ice MK	2.970	3.125
21	M-spectral	3.5	6.0
22	Blank	–	–
23	PK50 2mm	—	2.7
24	blank	–	–

Previous filter wheel arrangements are available here.