[in Japanese]

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Studies on color reproducibility of coated photographic objectives for the color photography are given. Experiments show that the blue sensitive emulsion of color films has ultra-violet sensitivity.
Through colorimetric calculation based on spectral sensitivities of color films, optimal thickness of objective coatings for exact color reproduction are determined according to the degree of ultra-violet absorption of objectives. Generally, purple coating is optimal for such objectives as F/3.5-4.5, magenta for F/2.8-2, amber for F/1.8-1.2.

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The four silver bromide emulsions, which contained 0, 2.5, 5. and 10mol% AgI respectively, were prepared, and stdudies on the relation between time of second ripening and sensitivity to light, X-ray and gamma-ray, and on the latent image distribution of each emulsion exposed to light, X- and Gamma-ray were carried out.
The following results were obtained.
(1) In the case of X-or gamma-ray exposure, sensitivity increase by second ripening was not so remarkable as in the case of light exposure, and especially in the case of pure silver bromide emulsion, sec ond ripening had no effect on increasing sensitivity to low energy X-ray, but a little to gamma-ray.
(2) The ratio of internal sensitivity to surface one was greater when exposed to X-or gamma- ray than when exposed to light. This means that the internallatent image is more easily formed by X-or gammaray exposure than by light exposure; this is a well known fact.
(3) It seemed that, in the case of X-ray exposure. the greater the content of AgI was, the greater the rate of increasing internal sensitivity to surface one became. In the case of gamma-ray exposure, however, this rate was maximum at 2.5 mol% Agi.

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The silver potentiometric titration has been tried with eighteen kinds of aza-indolizines, that is two kinds of diaza-indolizines, eleven kinds of triaza-indolizines and five kinds of tetraza-inzolines. Following results were obtained:
I. In comparison with some organic sulfur compounds, aza-indolizines generally show nobler potential at same pH.
2. Among aza-indolizines which have same substitution radical at the similer position, potential is less noble in the order of 2, 3, 7-triaza-indolizines, 2, 3, 4-triaza-indolizines and tetraza-indolizines,
3. Among 2, 3, 4-triaza-indolizine and tetraza-indolizine, compounds which have inactive radical as methyl etc. into the position of 5 and 7, do not react with silver ions. But at pH 10.0 and 11.0, the decomposition may occur because the different precipitation from that of buffer solution itself is found.
4. In triaza-indolizine, with the numbers of OH radical which is substituted the positios of 5 and 7. there are compounds which need one or two silver ions. That is to say that the compound having one OH radical reacts with silver salt at the ratio one to one and two OH radicals, one to two. While tetraza-indolizine need the silver salt in the ratio one to two even when one OH radical substitutes to the position of 5 or 7.
5. In triaza-indolizine, the effect with methyl, ethyl and phenyl radicals which substitute to the same position could not be concluded because of the shortage of example.

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On the preceding paper, the author had proposed an idea of three successive exposures with peculiar color filters to have a print of correct rendering of colors. In the present paper, this idea is extended. with good results. Among others, six cases are chosen:
a) Color positive made from three separate negatives of black and white either on color film or on the paper.
b) Color negative on film made from a color slide.
c) Color positive made from color slide by the reversal process.
d) Color positive made from color negative on the film and paper.
e) Color negative made directly in camera with successivexposures.
f) Color positive taken in camera and by the reversal process.

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