Studies in the photometry of lights of different colours / by Herbert E. Ives. : spectral luminosity curves obtained by the equality of brightness photometer and the flicker photometer under similar conditions.

  • Ives, Herbert Eugene, 1882-1953.
Date:
[1912]
Catalogue details

Licence: In copyright

Credit: Studies in the photometry of lights of different colours / by Herbert E. Ives. : spectral luminosity curves obtained by the equality of brightness photometer and the flicker photometer under similar conditions. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    fact that owing to differences in shape certain curves would have less weight than others it' plotted in terms o£ equal maxima or equality at any arbitrarily chosen wave-length. According to the results of the paper just previous in this series, the one thing common to all the curves would be their area when the comparison light and the light dispersed into a spectrum were identical. The data o£ all observers are given in Table L, with their mean. Table II. gives the mean values in terms of the Table I. Normal Spectrum Luminosity Curves of Eighteen Observers. Observer. •481 •498 •518 •537 •556 •576 •595 •615 •635 •655 [i 1. P.W.O. 3-4 5-9 1375 17-4 17-95 17-1 140 9-55 5-2 1-7 2. L.H.K. 4-15 7-1 155 18-7 18-6 16-5 12-2 75 3-65 1-15 3. E.J.E. 3-05 5-9 13-8 18-4 18-95 17-15 13-35 8-65 3-85 1-4 4. W.M.M. 3-6 7-4 15-2 18-45 19-05 16-65 12-45 7-75 3-8 1-15 5. M.D.O. 33 655 15-0 193 19-25 17-6 12-75 7-65 3-45 1-35 6. F.E.C. 2-3 5-05 13-9 17-9 19-1 1755 14-3 94 4-95 1-95 7. M.L.I. 325 5-45 12-75 17-8 18-9 17-8 137 9 05 4-55 1-9 8. M.L. 3-3 7-7 142 187 19-8 18-2 12-3 73 3-45 1-35 9. H.A.R. 3-3 6-9 14-2 17 7 17-8 17-2 13-45 90 4-65 2-00 10. L.R.Gl. 2-65 6-95 159 19-55 19-a 172 12-3 7-7 29 0-9 11. M.M. 3-9 7-2 14-7 17 35 18-5 16-65 13-15 8-05 340 1-2 12. C.F.L. 27 5-45 13-2 181 18-7 17*5 1415 9-2 4-9 1-6 13. A.J.S. 2-55 5-7^ J 5-2 19-05 195 17-45 135 8-25 41 1-4 14. A.W. 1-6 3*65 12-65 16-9 18-05 18-25 15-6 11-05 5-85 2-3 15. H.H.M. 2-6 61 14-85 18-0 19-45 17-8 1395 8-4 4-15 1-3 16. T.W.K 3-7 7-4 14-15 19 9 20-1 175 12-0 67 3-15 1-25 17. H.E.I. 30 6-1 15-35 18-75 19-3 17-4 13-45 8-25 3-9 1-5 18. G.C. 215 5-2 126 18-8 19-4 17-1 14-0 9-3 5-0 1-6 Mean 3-03 6-2 14-55 18-38 1903 17-47 1336 8 52 4-16 1-5 Table II. Relative Luminous Efficiencies of Spectral Radiations. X. X. •44 ii •029] •57 fx -948 •45 •047 •58 •875 •46 •073 • -x- •59 •763 •47 •107, •60 •635 •48 •154 •61 •509 •49 •235 •62 •387 •50 •363 •63 •272 •51 •596 •64 •175 •52 •794 •65 •104 •53 •912 •66 •068] •54 •977 •67 •044 I * ■55 1-000 •68 •026 J •56 •990 * Extrapolated.