Bryn Mawr College monographs . variedJ il a brightness match was obtained. The changes in thef^nsity of the colored light required to give the match were 305 STUDIES IN PSYCHOLOGY not made by varying the width of the coUimator sUt, asoften the case, because changes in the width of the colUmatorsht tend to give a variable purity of hght,—a condition whichwould have given us more trouble in the selection of our filtersto absorb stray light. Specially constructed sectored discswith a single open sector adjusted by a finely threaded micro-meter screw and provided with a Vernier reading to minutes,
Bryn Mawr College monographs . variedJ il a brightness match was obtained. The changes in thef^nsity of the colored light required to give the match were 305 STUDIES IN PSYCHOLOGY not made by varying the width of the coUimator sUt, asoften the case, because changes in the width of the colUmatorsht tend to give a variable purity of hght,—a condition whichwould have given us more trouble in the selection of our filtersto absorb stray light. Specially constructed sectored discswith a single open sector adjusted by a finely threaded micro-meter screw and provided with a Vernier reading to minutes,were used instead for this purpose. That is, the collimatorslit was set at a width which made the comparison field slightlybrighter than the standard field for the group of wave-lengthsin question and the gelatines required to absorb the alienwave-lengths were placed in position over the analyzing gelatines, as stated earlier in the paper, were held inplace by short clips fastened on either side of the slit to the. Fig. I front surface of the jaws, the edges of which formed the width of the collimator slit and the gelatines were thenkept constant, and the reductions needed to give the fourintensities were made by means of the sectored discs, insertedbetween the analyzing slit and the lens L^. In Table V are given the relative energy values of the stim-uli to give equal achromatic responses at the four photometricintensities used. These values are shown graphically in ChartIV. In constructing this chart as in case of all of the preced-ing charts, the wave-lengths are spaced to approximate thedistribution in the prismatic spectrum. The comparative sen-sitivity of the eye to the groups of wave-lengths used shouldof course be as the reciprocals of the relative energy valuesrequired to give equal achromatic responses. The values ofthese reciprocals are given in Table VI. A graphic^ repre-sentation of the results for the highest intensity in this tableis given i
Size: 2972px × 841px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorbrynmawr, bookcentury1900, bookdecade1900, bookyear1901
