# Subaru Telescope Optical Tertiary Mirror In-Situ Measured Reflectivity # Coated with Aluminum on 2025-12-16 # Opened the vacuum chamber: No information # Measured with Subaru Portable Spectrophotometer (SPS) on 2026-03-04 (78 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 92.50 92.21 91.66 998 91.53 92.21 92.61 996 91.56 92.35 92.10 994 93.72 91.99 92.53 992 91.20 92.09 92.32 990 92.03 91.69 92.06 988 92.19 92.10 92.42 986 92.57 92.69 91.50 984 92.20 92.73 92.29 982 92.20 92.92 92.51 980 91.99 91.34 92.23 978 91.65 91.03 92.75 976 91.76 91.22 92.64 974 92.08 91.08 92.22 972 91.63 91.75 92.06 970 91.90 92.30 92.50 968 91.80 92.22 91.85 966 91.73 91.87 91.69 964 91.79 91.74 92.05 962 90.95 90.67 92.27 960 90.42 91.63 91.16 958 91.30 90.98 91.39 956 92.03 92.19 91.30 954 91.05 90.83 91.08 952 90.93 91.10 91.69 950 90.71 91.44 91.31 948 91.19 91.09 90.97 946 90.74 91.62 90.70 944 90.72 91.11 91.34 942 90.96 91.50 91.50 940 90.78 90.75 91.63 938 90.82 91.17 90.68 936 90.62 90.66 90.71 934 90.25 90.41 90.74 932 90.36 90.12 91.02 930 90.24 90.02 90.52 928 90.58 90.13 90.02 926 90.11 90.32 90.52 924 89.93 89.88 90.09 922 90.33 90.01 90.08 920 89.19 90.03 89.94 918 89.62 89.77 89.84 916 89.63 89.60 90.06 914 89.85 89.21 89.70 912 89.34 89.09 89.69 910 88.79 89.17 89.20 908 88.77 89.20 89.04 906 89.15 88.83 89.04 904 88.57 89.21 89.35 902 88.83 88.75 89.28 900 88.99 88.98 88.72 898 88.73 88.61 88.73 896 88.18 88.33 88.88 894 88.53 88.29 88.51 892 88.25 88.57 88.46 890 87.90 88.35 88.12 888 88.25 87.93 87.98 886 87.99 87.97 88.06 884 87.66 87.48 87.92 882 87.32 87.21 87.60 880 87.55 87.69 87.35 878 87.22 87.25 87.40 876 87.10 86.94 87.54 874 86.85 87.09 87.08 872 86.88 86.99 87.23 870 86.67 86.50 86.88 868 86.59 86.67 86.89 866 86.57 86.50 86.82 864 86.53 86.84 86.67 862 86.05 86.09 86.18 860 86.39 86.00 86.64 858 86.39 85.98 86.06 856 86.25 85.72 85.65 854 85.53 86.02 85.69 852 85.62 85.67 86.13 850 85.98 85.37 85.61 848 85.49 85.30 85.86 846 84.87 85.60 85.64 844 85.54 85.40 85.69 842 85.14 85.45 85.30 840 85.30 85.56 85.39 838 85.45 84.95 85.40 836 85.84 84.71 85.43 834 84.98 84.40 84.97 832 84.60 84.79 85.02 830 84.89 85.07 84.83 828 84.68 85.07 85.30 826 84.99 84.88 85.26 824 85.28 84.82 85.26 822 85.02 85.01 84.96 820 85.05 85.01 85.07 818 84.43 85.08 85.35 816 85.07 84.86 85.08 814 85.04 85.00 84.95 812 85.01 84.94 84.90 810 85.08 85.24 85.28 808 85.09 85.05 85.24 806 85.16 85.10 85.20 804 84.84 85.23 84.81 802 85.37 85.04 85.09 800 85.60 85.16 85.21 798 85.27 85.02 85.45 796 85.09 85.29 85.26 794 85.47 85.49 85.38 792 85.35 85.32 85.55 790 85.67 85.55 85.62 788 85.50 85.38 85.42 786 85.45 85.63 85.58 784 85.88 85.67 85.84 782 85.49 85.66 85.88 780 85.84 85.94 85.64 778 86.00 85.78 86.21 776 85.97 86.13 85.88 774 86.22 85.85 86.04 772 85.68 85.85 86.20 770 85.78 86.30 86.10 768 86.16 86.14 86.21 766 86.27 86.21 86.35 764 86.34 86.37 86.44 762 86.10 86.15 86.29 760 86.40 86.51 86.55 758 86.74 86.50 86.81 756 86.51 86.70 86.74 754 86.52 86.64 87.06 752 86.73 86.72 86.86 750 86.77 86.63 87.00 748 86.84 86.74 86.70 746 86.67 86.64 87.07 744 86.65 86.78 86.96 742 86.79 86.90 87.34 740 86.92 86.97 87.15 738 87.28 87.30 87.11 736 87.28 87.10 87.33 734 87.23 87.22 87.25 732 87.29 87.18 87.49 730 87.21 87.39 87.41 728 87.37 87.37 87.30 726 87.39 87.39 87.55 724 87.59 87.52 87.68 722 87.35 87.59 87.74 720 87.53 87.42 87.65 718 87.71 87.58 87.44 716 87.60 87.62 87.69 714 87.69 87.58 87.68 712 87.75 87.53 88.11 710 87.73 87.53 87.85 708 88.28 87.55 87.93 706 87.94 87.75 88.03 704 87.99 87.90 87.97 702 87.80 87.91 88.16 700 87.92 87.67 88.16 698 88.04 88.04 87.98 696 88.15 88.02 88.15 694 87.94 87.92 88.22 692 88.22 87.93 88.19 690 88.16 88.13 88.31 688 88.35 88.11 88.43 686 88.29 88.09 88.14 684 88.32 88.28 88.23 682 88.51 88.37 88.30 680 88.37 88.20 88.53 678 88.53 88.32 88.37 676 88.47 88.43 88.49 674 88.53 88.38 88.47 672 88.59 88.54 88.74 670 88.69 88.53 88.73 668 88.59 88.34 88.71 666 88.41 88.48 88.67 664 88.60 88.44 88.68 662 88.64 88.46 88.81 660 88.56 88.59 88.72 658 88.73 88.73 88.80 656 88.71 88.62 88.64 654 88.64 88.79 88.87 652 88.76 88.69 89.09 650 88.91 88.73 88.89 648 88.96 88.94 88.90 646 88.94 88.73 89.08 644 89.00 88.93 89.16 642 88.99 89.12 89.04 640 89.17 89.03 89.15 638 89.31 88.86 89.06 636 89.08 88.94 88.95 634 89.09 89.00 89.37 632 88.99 88.94 89.32 630 89.00 89.10 89.23 628 89.21 88.84 89.32 626 89.18 89.30 89.15 624 89.30 89.09 89.35 622 88.95 89.21 89.33 620 89.33 89.15 89.45 618 89.38 89.23 89.19 616 89.48 89.21 89.19 614 89.35 89.09 89.22 612 89.40 89.41 89.56 610 89.21 89.18 89.42 608 89.25 89.41 89.42 606 89.38 89.17 89.38 604 89.43 89.26 89.51 602 89.48 89.31 89.52 600 89.54 89.40 89.63 598 89.56 89.59 89.66 596 89.70 89.61 89.71 594 89.51 89.36 89.69 592 89.46 89.40 89.69 590 89.64 89.43 89.83 588 89.75 89.36 89.80 586 89.46 89.53 89.76 584 89.61 89.66 89.81 582 89.57 89.38 89.75 580 89.55 89.55 89.93 578 89.74 89.44 89.76 576 89.68 89.49 89.68 574 89.72 89.62 89.80 572 89.91 89.65 89.86 570 89.62 89.49 89.98 568 89.73 89.76 90.14 566 89.60 89.61 89.94 564 89.68 89.79 90.05 562 89.89 89.72 90.13 560 89.84 89.64 89.83 558 89.88 89.74 89.84 556 89.97 89.83 90.00 554 89.80 89.65 89.86 552 89.79 89.82 89.91 550 89.95 89.65 89.97 548 89.78 89.64 89.95 546 89.68 89.83 90.02 544 89.86 89.70 89.87 542 89.87 89.89 89.84 540 89.94 89.71 90.09 538 90.02 89.84 89.88 536 89.83 89.77 90.30 534 89.89 89.98 90.17 532 90.05 89.89 90.28 530 90.00 89.79 90.16 528 90.11 89.85 90.28 526 90.02 89.90 90.26 524 90.20 90.14 90.32 522 89.94 90.27 90.03 520 90.05 90.21 89.95 518 90.12 90.32 90.26 516 90.34 90.08 89.94 514 89.96 90.03 90.31 512 90.15 90.16 90.27 510 90.09 89.92 90.18 508 89.90 90.19 90.33 506 90.04 90.15 90.10 504 90.10 90.09 90.38 502 90.13 90.18 90.12 500 90.09 90.15 90.33 498 90.26 90.09 90.54 496 90.05 90.11 90.44 494 90.20 90.18 90.27 492 90.14 90.24 90.35 490 90.21 90.01 90.36 488 90.51 90.21 90.43 486 90.49 90.30 90.44 484 90.16 90.31 90.35 482 90.52 90.26 90.35 480 90.05 89.89 90.39 478 90.25 90.14 90.21 476 90.43 90.36 90.38 474 90.29 90.30 90.49 472 90.18 90.06 90.58 470 90.13 90.20 90.32 468 90.30 90.09 90.44 466 89.96 89.75 90.27 464 90.28 90.15 90.34 462 90.18 90.24 90.56 460 90.11 90.30 90.27 458 90.48 90.37 90.21 456 90.66 89.93 90.60 454 90.77 90.47 90.75 452 90.00 90.50 90.86 450 90.58 90.24 90.36 448 90.48 90.24 90.59 446 90.57 90.16 90.62 444 90.20 90.11 90.31 442 90.61 90.41 90.29 440 90.33 90.16 90.41 438 90.17 90.28 90.66 436 90.12 90.75 90.64 434 90.26 90.75 90.36 432 90.71 90.74 90.43 430 90.26 90.68 91.06 428 90.66 89.99 90.73 426 90.32 90.49 90.66 424 90.39 90.74 90.43 422 89.71 91.10 90.60 420 90.42 90.40 90.54 418 90.17 89.98 90.27 416 90.49 90.27 90.25 414 90.17 90.42 90.36 412 90.63 90.09 90.56 410 90.33 90.47 90.67 408 90.68 89.69 90.35 406 90.58 90.09 90.62 404 90.00 90.65 90.77 402 90.34 89.87 90.63 400 90.43 90.59 90.41 398 90.24 90.26 90.86 396 90.10 89.66 90.21 394 89.76 89.84 90.36 392 90.14 90.21 90.26 390 90.10 90.23 90.80 388 89.77 90.33 90.64 386 89.90 90.01 90.87 384 89.98 89.89 90.54 382 90.16 91.55 90.63 380 90.70 91.69 89.03 1650 96.45 96.39 96.43 1640 96.46 96.41 96.42 1630 96.45 96.40 96.43 1620 96.46 96.42 96.44 1610 96.45 96.42 96.44 1600 96.46 96.41 96.44 1590 96.45 96.41 96.42 1580 96.45 96.39 96.43 1570 96.44 96.40 96.43 1560 96.42 96.38 96.41 1550 96.41 96.37 96.40 1540 96.40 96.37 96.39 1530 96.39 96.34 96.37 1520 96.37 96.33 96.37 1510 96.36 96.32 96.35 1500 96.35 96.31 96.34 1490 96.33 96.29 96.33 1480 96.31 96.28 96.31 1470 96.30 96.26 96.30 1460 96.28 96.24 96.29 1450 96.27 96.22 96.26 1440 96.24 96.20 96.26 1430 96.23 96.19 96.22 1420 96.19 96.16 96.22 1410 96.19 96.15 96.20 1400 96.15 96.13 96.17 1390 96.13 96.10 96.16 1380 96.12 96.08 96.12 1370 96.08 96.05 96.11 1360 96.06 96.03 96.08 1350 96.04 95.99 96.05 1340 96.01 95.96 96.02 1330 95.99 95.93 96.00 1320 95.95 95.90 95.97 1310 95.92 95.87 95.94 1300 95.89 95.83 95.90 1290 95.85 95.79 95.87 1280 95.82 95.77 95.84 1270 95.77 95.73 95.79 1260 95.74 95.69 95.75 1250 95.70 95.65 95.72 1240 95.65 95.60 95.67 1230 95.60 95.55 95.62 1220 95.56 95.51 95.58 1210 95.50 95.46 95.53 1200 95.46 95.39 95.47 1190 95.39 95.35 95.42 1180 95.33 95.28 95.36 1170 95.28 95.22 95.30 1160 95.20 95.16 95.23 1150 95.14 95.09 95.17 1140 95.06 95.02 95.10 1130 94.98 94.93 95.02 1120 94.90 94.85 94.93 1110 94.81 94.75 94.86 1100 94.72 94.66 94.74 1090 94.61 94.54 94.64 1080 94.49 94.43 94.54 1070 94.38 94.31 94.41 1060 94.23 94.17 94.27 1050 94.08 94.03 94.13 1040 93.92 93.87 93.98 1030 93.77 93.70 93.80 1020 93.57 93.51 93.62 1010 93.36 93.31 93.41 1000 93.13 93.07 93.18 990 92.88 92.82 92.92 980 92.60 92.53 92.66 970 92.28 92.22 92.34 960 91.92 91.88 92.01 950 91.54 91.49 91.60