DOI Seite / Zitierlink:
https://doi.org/10.11588/diglit.62828#0440
jefts in this manner. Now it is evident, therefore, that the
fide or plane a will have moft of the light, becauie the rays fall
nearly perpendicular on it, which confequently excludes all
ihadow; but the plane or fide b receives the faid rays obliquely,
and in proportion thereto occafions a ihadow, becaufe the light
partly miffes the furface. The plane e is totally in ihadow, be-
caufe the ray r cannot touch that furface.
Secondly, in fliadows of this kind the contraft of light and
fhade is not fo ftrong as when the fun’s rays fall on objects;
the light is not fo glaring, nor the fliadows fo black. The out-
lines of fuch fliadows ought not to be ftrongly defined, but
faint, and fometimes indiftindt, efpecially when the light is fup-
pofed to come from different apertures.
Laftly, fuch objects as are fuppofed to be viewed in a room
have their upper parts lighteft; but the lighted: parts will bear
a dint, and fometimes confiderable, fo that there will not be
much oppofition of light and fhade in their different furfaces.
It is requifite to confider the natural colours of objeffs, in
order to fix the tone and true fcale of light fuitable to them
The lighteft part of an object that is of itfelf black, would be
* This is alfo necefiary when the fun is fuppofed to fhine.
a fhade
fide or plane a will have moft of the light, becauie the rays fall
nearly perpendicular on it, which confequently excludes all
ihadow; but the plane or fide b receives the faid rays obliquely,
and in proportion thereto occafions a ihadow, becaufe the light
partly miffes the furface. The plane e is totally in ihadow, be-
caufe the ray r cannot touch that furface.
Secondly, in fliadows of this kind the contraft of light and
fhade is not fo ftrong as when the fun’s rays fall on objects;
the light is not fo glaring, nor the fliadows fo black. The out-
lines of fuch fliadows ought not to be ftrongly defined, but
faint, and fometimes indiftindt, efpecially when the light is fup-
pofed to come from different apertures.
Laftly, fuch objects as are fuppofed to be viewed in a room
have their upper parts lighteft; but the lighted: parts will bear
a dint, and fometimes confiderable, fo that there will not be
much oppofition of light and fhade in their different furfaces.
It is requifite to confider the natural colours of objeffs, in
order to fix the tone and true fcale of light fuitable to them
The lighteft part of an object that is of itfelf black, would be
* This is alfo necefiary when the fun is fuppofed to fhine.
a fhade