The universal practice which painters adopt on the walls of chapels
is greatly and reasonably to be condemned. Inasmuch as they
represent one historical subject on one level with a landscape and
buildings, and then go up a step and paint another, varying the
point [of sight], and then a third and a fourth, in such a way as
that on one wall there are 4 points of sight, which is supreme folly
in such painters. We know that the point of sight is opposite the
eye of the spectator of the scene; and if you would [have me] tell
you how to represent the life of a saint divided into several
pictures on one and the same wall, I answer that you must set out
the foreground with its point of sight on a level with the eye of
the spectator of the scene, and upon this plane represent the more
important part of the story large and then, diminishing by degrees
the figures, and the buildings on various hills and open spaces, you
can represent all the events of the history. And on the remainder of
the wall up to the top put trees, large as compared with the
figures, or angels if they are appropriate to the story, or birds or
clouds or similar objects; otherwise do not trouble yourself with it
for your whole work will be wrong.
543.
A PICTURE OF OBJECTS IN PERSPECTIVE WILL LOOK MORE LIFELIKE WHEN
SEEN FROM THE POINT FROM WHICH THE OBJECTS WERE DRAWN.
If you want to represent an object near to you which is to have the
effect of nature, it is impossible that your perspective should not
look wrong, with every false relation and disagreement of proportion
that can be imagined in a wretched work, unless the spectator, when
he looks at it, has his eye at the very distance and height and
direction where the eye or the point of sight was placed in doing
this perspective. Hence it would be necessary to make a window, or
rather a hole, of the size of your face through which you can look
at the work; and if you do this, beyond all doubt your work, if it
is correct as to light and shade, will have the effect of nature;
nay you will hardly persuade yourself that those objects are
painted; otherwise do not trouble yourself about it, unless indeed
you make your view at least 20 times as far off as the greatest
width or height of the objects represented, and this will satisfy
any spectator placed anywhere opposite to the picture.
If you want the proof briefly shown, take a piece of wood in the
form of a little column, eight times as high as it is thick, like a
column without any plinth or capital; then mark off on a flat wall
40 equal spaces, equal to its width so that between them they make
40 columns resembling your little column; you then must fix,
opposite the centre space, and at 4 braccia from the wall, a thin
strip of iron with a small round hole in the middle about as large
as a big pearl. Close to this hole place a light touching it. Then
place your column against each mark on the wall and draw the outline
of its shadow; afterwards shade it and look through the hole in the
iron plate.
[Footnote: In the original there is a wide space between lines 3 and
4 in which we find two sketches not belonging to the text. It is
unnecessary to give prominence to the points in which my reading
differs from that of M. RAVAISSON or to justify myself, since they
are all of secondary importance and can also be immediately verified
from the photograph facsimile in his edition.]
544.
A diminished object should be seen from the same distance, height
and direction as the point of sight of your eye, or else your
knowledge will produce no good effect.
And if you will not, or cannot, act on this principle--because as
the plane on which you paint is to be seen by several persons you
would need several points of sight which would make it look
discordant and wrong--place yourself at a distance of at least 10
times the size of the objects.
The lesser fault you can fall into then, will be that of
representing all the objects in the foreground of their proper size,
and on whichever side you are standing the objects thus seen will
diminish themselves while the spaces between them will have no
definite ratio. For, if you place yourself in the middle of a
straight row [of objects], and look at several columns arranged in a
line you will see, beyond a few columns separated by intervals, that
the columns touch; and beyond where they touch they cover each
other, till the last column projects but very little beyond the last
but one. Thus the spaces between the columns are by degrees entirely
lost. So, if your method of perspective is good, it will produce the
same effect; this effect results from standing near the line in
which the columns are placed. This method is not satisfactory unless
the objects seen are viewed from a small hole, in the middle of
which is your point of sight; but if you proceed thus your work will
be perfect and will deceive the beholder, who will see the columns
as they are here figured.
Here the eye is in the middle, at the point _a_ and near to the
columns.
[Footnote: The diagram which stands above this chapter in the
original with the note belonging to it: "a b _e la ripruova_" (_a b_
is the proof) has obviously no connection with the text. The second
sketch alone is reproduced and stands in the original between lines
22 and 23.]
545.
If you cannot arrange that those who look at your work should stand
at one particular point, when constructing your work, stand back
until your eye is at least 20 times as far off as the greatest
height and width of your work. This will make so little difference
when the eye of the spectator moves, that it will be hardly
appreciable, and it will look very good.
If the point of sight is at _t_ you would make the figures on the
circle _d b e_ all of one size, as each of them bears the same
relation to the point _t_. But consider the diagram given below and
you will see that this is wrong, and why I shall make _b_ smaller
than _d e_ [Footnote 8: The second diagram of this chapter stands in
the original between lines 8 and 9.].
It is easy to understand that if 2 objects equal to each other are
placed side by side the one at 3 braccia distance looks smaller than
that placed at 2 braccia. This however is rather theoretical than
for practice, because you stand close by [Footnote 11: Instead of
'_se preso_' (=_sie presso_) M. RAVAISSON reads '_sempre se_' which
gives rise to the unmeaning rendering: '_parceque toujours_ ...'].
All the objects in the foreground, whether large or small, are to be
drawn of their proper size, and if you see them from a distance they
will appear just as they ought, and if you see them close they will
diminish of themselves.
[Footnote 15: Compare No. 526 line 18.] Take care that the vertical
plan on which you work out the perspective of the objects seen is of
the same form as the wall on which the work is to be executed.
546.