# Subaru Telescope Cassegrain Optical Secondary Mirror In-Situ Measured Reflectivity # Coated with Aluminum at Pilkington on 1998-12-17 # Opened the vacuum chamber: No information # Measured with Subaru Portable Spectrophotometer (SPS) on 2021-01-12 (8062 days after) # Measured three times # Data between 950 nm and 1650 nm are also available (SPS-XWW). # Contact: Hirofumi Okita (okita14@naoj.org) # # Wavelength (nm) #1 #2 #3 1000 90.70 91.34 92.29 998 91.29 92.18 91.24 996 91.58 91.96 91.09 994 91.66 91.41 91.50 992 91.30 91.25 91.49 990 91.91 90.98 91.21 988 91.33 91.30 90.87 986 91.04 91.85 91.51 984 90.85 90.96 90.04 982 90.98 90.95 91.36 980 90.89 90.89 91.07 978 90.84 90.65 91.69 976 90.88 90.55 91.74 974 91.04 91.12 91.11 972 90.66 90.80 91.11 970 90.52 91.01 91.11 968 90.27 91.20 90.36 966 89.95 90.89 90.67 964 89.81 89.83 91.18 962 90.18 91.25 90.52 960 90.57 90.60 90.81 958 90.11 90.37 90.29 956 90.11 90.43 89.96 954 90.60 90.87 90.35 952 90.09 90.11 90.40 950 89.90 90.43 90.58 948 89.82 89.96 90.23 946 90.10 89.81 90.05 944 89.66 90.49 90.18 942 89.47 89.59 89.84 940 89.75 90.19 90.09 938 89.34 89.38 89.95 936 89.72 89.55 89.03 934 89.19 89.55 89.44 932 88.85 89.73 89.60 930 89.36 88.86 89.09 928 88.67 89.00 89.77 926 88.57 88.97 88.89 924 88.64 88.80 88.80 922 88.65 88.57 88.86 920 88.66 88.71 88.62 918 88.35 88.53 88.44 916 88.30 88.46 88.47 914 87.97 88.40 88.54 912 87.98 87.84 88.41 910 87.50 87.85 88.34 908 87.70 87.81 87.72 906 87.26 87.83 88.34 904 87.49 87.68 87.78 902 87.37 87.38 87.78 900 87.25 87.43 87.82 898 87.04 87.11 87.33 896 86.80 86.92 86.96 894 86.46 86.70 87.00 892 86.81 86.70 87.10 890 86.65 86.63 86.90 888 86.15 86.47 86.79 886 86.05 86.06 86.51 884 85.90 86.05 86.32 882 85.65 85.75 85.70 880 85.82 85.76 85.84 878 85.23 85.67 85.68 876 85.25 85.24 85.35 874 85.08 85.29 85.48 872 84.99 85.18 85.44 870 85.19 84.94 85.33 868 84.78 85.37 84.88 866 84.29 84.67 85.05 864 84.37 84.85 84.81 862 83.88 84.44 84.38 860 84.06 84.48 84.28 858 84.11 84.30 83.96 856 83.92 84.20 84.06 854 83.71 83.99 83.94 852 83.86 83.80 83.93 850 83.47 83.69 83.98 848 83.16 83.31 83.75 846 83.29 83.53 83.67 844 83.38 83.55 83.54 842 83.43 83.56 83.31 840 83.09 83.39 83.27 838 83.30 83.57 83.57 836 83.21 83.06 83.30 834 83.17 83.05 83.04 832 83.02 83.22 82.84 830 83.08 83.23 83.63 828 83.02 82.95 83.49 826 83.20 83.30 83.45 824 83.20 83.23 83.36 822 83.09 83.00 83.33 820 82.84 82.99 83.09 818 83.03 83.29 83.41 816 83.29 83.07 83.09 814 82.86 83.43 83.44 812 83.07 82.93 83.35 810 83.04 83.57 83.18 808 83.27 83.33 83.38 806 83.25 83.62 83.36 804 83.29 83.19 83.33 802 83.13 83.58 83.68 800 83.34 83.70 83.57 798 83.47 83.53 84.03 796 83.36 83.67 83.74 794 83.72 83.97 83.82 792 83.41 84.00 83.96 790 83.59 83.82 83.88 788 83.78 83.58 84.14 786 83.63 83.73 84.15 784 84.08 84.04 84.15 782 83.78 84.18 84.32 780 83.98 83.85 84.24 778 84.23 84.35 84.25 776 84.32 84.64 84.37 774 84.24 84.56 84.65 772 84.59 84.53 84.38 770 84.47 84.48 84.68 768 84.22 84.74 84.89 766 84.49 84.84 84.78 764 84.32 84.81 84.86 762 84.77 84.96 84.88 760 84.70 84.97 85.12 758 84.67 84.89 85.09 756 84.77 85.03 85.35 754 84.80 84.99 85.08 752 84.97 85.38 85.42 750 84.89 85.46 85.27 748 85.02 85.22 85.28 746 85.45 85.43 85.26 744 85.26 85.62 85.39 742 85.17 85.44 85.71 740 85.62 85.73 85.31 738 85.37 85.56 85.65 736 85.55 85.59 85.77 734 85.51 85.60 85.96 732 85.58 85.61 85.70 730 85.40 85.90 85.79 728 85.72 85.94 86.07 726 85.80 85.76 85.84 724 85.73 85.90 86.11 722 85.74 86.11 85.96 720 85.77 85.96 85.97 718 85.83 86.07 86.04 716 85.87 86.03 86.15 714 85.95 86.15 86.31 712 86.09 85.91 86.13 710 85.83 85.97 86.26 708 86.13 86.26 86.47 706 86.01 86.29 86.30 704 85.94 86.36 86.48 702 86.19 86.12 86.51 700 86.30 86.33 86.45 698 86.30 86.48 86.32 696 86.05 86.44 86.57 694 86.45 86.34 86.36 692 86.32 86.49 86.38 690 86.18 86.42 86.48 688 86.37 86.48 86.50 686 86.52 86.69 86.45 684 86.35 86.61 86.70 682 86.52 86.48 86.82 680 86.34 86.77 86.79 678 86.25 86.69 86.63 676 86.57 86.74 86.74 674 86.52 86.74 86.74 672 86.65 86.62 86.67 670 86.65 86.76 86.64 668 86.69 86.91 86.77 666 86.73 86.78 86.81 664 86.58 86.89 86.86 662 86.88 86.98 86.86 660 86.76 86.77 86.94 658 86.72 86.88 87.02 656 86.77 86.83 86.95 654 86.81 87.02 86.99 652 86.89 87.20 87.19 650 86.85 86.79 87.08 648 86.99 86.94 87.01 646 86.84 86.81 87.12 644 86.90 87.08 86.98 642 86.91 86.86 87.13 640 86.97 87.20 87.14 638 86.94 87.15 87.12 636 86.91 87.21 87.11 634 86.91 87.24 87.23 632 86.92 87.04 87.00 630 86.86 86.84 87.15 628 87.03 87.20 87.21 626 86.99 87.10 87.12 624 86.91 87.29 87.19 622 87.14 87.30 87.06 620 87.03 87.31 87.32 618 86.99 87.10 87.14 616 86.97 87.12 87.24 614 86.95 87.10 87.22 612 86.87 87.08 87.07 610 87.17 87.25 87.17 608 86.93 87.21 87.05 606 87.08 87.08 87.09 604 87.02 87.37 87.17 602 87.03 87.32 87.21 600 86.92 87.24 87.28 598 87.05 87.26 87.27 596 87.12 87.30 87.21 594 87.10 87.24 87.12 592 87.00 87.32 87.32 590 87.11 87.22 86.96 588 87.01 87.34 87.05 586 87.02 87.31 87.39 584 87.12 87.14 87.22 582 86.98 87.24 87.17 580 86.95 87.27 87.30 578 87.22 87.17 86.98 576 86.98 87.21 87.14 574 87.01 87.37 87.19 572 87.32 87.07 87.17 570 87.04 87.32 87.27 568 87.16 87.07 86.89 566 86.98 87.21 87.11 564 86.91 87.40 87.29 562 86.94 87.15 87.17 560 87.16 87.10 87.13 558 87.04 87.10 87.09 556 87.10 87.22 87.32 554 86.82 86.91 87.10 552 87.05 87.21 87.13 550 86.91 87.09 87.08 548 86.94 86.91 87.05 546 86.56 87.19 86.89 544 87.25 87.14 87.18 542 86.85 86.84 86.94 540 86.90 87.09 87.15 538 87.05 87.13 87.23 536 86.96 87.28 86.99 534 86.80 87.24 87.15 532 86.81 87.14 87.04 530 87.12 87.20 87.14 528 86.99 87.14 87.07 526 86.88 87.10 87.02 524 86.80 86.90 86.83 522 86.80 87.23 86.93 520 86.71 87.16 86.73 518 86.87 87.10 86.89 516 86.83 86.87 86.76 514 86.91 86.79 86.92 512 86.93 86.84 87.00 510 86.73 87.02 86.74 508 86.58 86.97 86.79 506 86.72 87.18 86.73 504 86.65 86.88 86.82 502 86.61 86.72 86.77 500 86.70 86.94 86.68 498 86.64 86.78 86.71 496 86.42 86.76 86.78 494 86.46 86.89 86.75 492 86.53 86.95 86.75 490 86.18 86.74 86.63 488 86.43 86.83 86.60 486 86.65 86.60 86.42 484 86.39 86.60 86.55 482 86.32 86.57 86.69 480 86.35 86.64 86.45 478 86.13 86.36 86.40 476 86.35 86.33 86.58 474 86.47 86.64 86.40 472 86.54 86.57 86.20 470 86.24 86.54 86.39 468 86.23 86.50 86.03 466 86.08 86.64 86.19 464 86.13 86.52 86.11 462 86.08 86.25 86.16 460 85.92 86.22 86.26 458 85.93 86.00 86.59 456 86.34 86.10 85.78 454 85.60 86.35 86.23 452 85.50 86.02 86.10 450 85.68 85.81 85.87 448 85.85 86.17 85.96 446 85.64 85.83 85.91 444 85.95 86.14 85.88 442 85.26 85.68 85.70 440 85.85 86.12 85.50 438 85.57 85.43 85.43 436 84.95 85.24 85.15 434 85.58 85.45 85.60 432 85.15 85.80 85.81 430 85.36 85.33 85.58 428 85.19 85.19 85.53 426 85.57 85.38 85.84 424 85.99 85.45 85.33 422 85.37 85.25 85.59 420 85.06 85.48 85.48 418 84.84 85.11 84.74 416 85.03 85.26 84.76 414 85.07 85.30 84.83 412 85.17 85.63 84.61 410 84.63 84.47 85.11 408 84.53 84.99 85.06 406 84.61 85.01 84.95 404 84.14 85.00 84.74 402 85.06 84.31 84.85 400 84.71 84.89 84.71 398 84.26 84.58 84.80 396 84.23 84.62 84.41 394 84.22 84.61 84.39 392 84.20 84.41 84.32 390 84.40 83.70 84.62 388 83.97 84.27 83.82 386 84.13 84.81 84.11 384 83.95 84.61 84.18 382 83.91 85.01 83.27 380 84.57 84.18 83.00 1650 95.89 95.96 96.04 1640 95.89 95.96 96.06 1630 95.90 95.99 96.06 1620 95.90 95.99 96.07 1610 95.91 95.99 96.08 1600 95.91 96.00 96.07 1590 95.89 95.99 96.07 1580 95.89 95.98 96.06 1570 95.87 95.97 96.05 1560 95.87 95.96 96.05 1550 95.85 95.95 96.03 1540 95.85 95.94 96.03 1530 95.84 95.93 96.02 1520 95.83 95.92 96.00 1510 95.80 95.91 95.98 1500 95.80 95.90 95.97 1490 95.78 95.88 95.96 1480 95.77 95.87 95.95 1470 95.74 95.85 95.92 1460 95.72 95.83 95.91 1450 95.71 95.81 95.89 1440 95.69 95.79 95.87 1430 95.66 95.77 95.85 1420 95.64 95.75 95.83 1410 95.63 95.74 95.81 1400 95.59 95.71 95.79 1390 95.57 95.68 95.76 1380 95.54 95.66 95.74 1370 95.51 95.63 95.70 1360 95.49 95.60 95.68 1350 95.46 95.58 95.65 1340 95.42 95.54 95.61 1330 95.39 95.51 95.59 1320 95.35 95.48 95.56 1310 95.32 95.44 95.51 1300 95.28 95.42 95.48 1290 95.24 95.38 95.45 1280 95.20 95.33 95.41 1270 95.17 95.29 95.37 1260 95.12 95.25 95.33 1250 95.08 95.21 95.27 1240 95.03 95.16 95.23 1230 94.98 95.11 95.19 1220 94.93 95.06 95.13 1210 94.88 95.00 95.08 1200 94.80 94.93 95.01 1190 94.74 94.88 94.95 1180 94.68 94.80 94.89 1170 94.61 94.74 94.82 1160 94.53 94.67 94.74 1150 94.46 94.60 94.67 1140 94.38 94.50 94.58 1130 94.29 94.42 94.49 1120 94.19 94.33 94.39 1110 94.08 94.22 94.29 1100 93.98 94.12 94.20 1090 93.87 93.99 94.07 1080 93.73 93.88 93.95 1070 93.59 93.74 93.79 1060 93.45 93.58 93.66 1050 93.29 93.42 93.48 1040 93.11 93.24 93.32 1030 92.91 93.05 93.11 1020 92.70 92.83 92.91 1010 92.46 92.59 92.67 1000 92.19 92.34 92.41 990 91.91 92.06 92.13 980 91.58 91.72 91.79 970 91.23 91.38 91.45 960 90.84 90.96 91.05 950 90.38 90.53 90.59