ALFOSC grisms' health status

Grism Status and Remarks Date
3 Clean, undamaged 6/2004
4
5 Not clean 6/2004
6
7 Fingerprint on grating, and hair/scratch at rim.
8 OK
9 Clean, undamaged 6/2004
10 Not clean; 4mm scratch on grating side, about 1cm from center 7/2004
11 Many small blemishes on grating 6/2004
12 Wide CD grism; coating/resin pealing off along outer 4mm rim 6/2004
13 Some scratches on grating 6/2004
13 Clean, undamaged 6/2004
14
15 Clean, undamaged 6/2004

16 Has a mask around holder to stop a central ghost; u-shaped scratch on grating 7mm from rim 6/2004
16 Is superseded by grism #18 since 2017: use grism #18 instead of #16 12/2023

17
18
19
20

All grisms are OK to use, but see remark about #16.