The first Yff circles triangle is the triangle formed by the centers of the first triplet of Yff circles.
It is homothetic to the reference
triangle at its incenter, with directed scale factor
,
where 
and 
are the inradius and circumradius
of the reference triangle, respectively (F. M. Jackson,
pers. comm., June 7, 2007).
Let 
be the image of a point 
under this homothety and let 
be its image under the homothety of the second
Yff circles triangle, with scale factor 
. Define 
and 
similarly. If 
, 
, and the incenter are not collinear,
the cross-joins 
and 
meet at the midpoint of
(F. M. Jackson, pers. comm., June 7, 2007).
The following table gives the centers of the first Yff circles triangle in terms of the centers of the reference triangle for
Kimberling centers 
with 
.
 | center of first Yff circles triangle |  | center of reference triangle |
 | incenter |  | incenter |
 | circumcenter |  | internal similitude center of circumcircle and incircle |
 | orthocenter |  | center of the first Johnson-Yff circle |
 | nine-point center |  | Johnson midpoint |
 | symmedian point |  | intersection of lines  and  |
 | isogonal
conjugate of  |  | Mimosa transform of  |
