  CCD UBVRi photometry of the final helium flash object V4334 Sgr (Sakurai's
Object), carried out during 1997 - 1999, is presented, and the light curve from
its pre-discovery rise to the dust obscuration phase is constructed. The
optical light curve can be divided into four sections, the rise to maximum, the
maximum, the dust onset, and the massive dust shell phase. The color indices
show a general increase with time, first because of the photospheric expansion
and cooling, and later because of the dust forming events. The energy
distributions for the years 1996 - 1999 show that an increasing part of the
energy is radiated at infrared wavelengths. In 1996, the infrared excess is
likely caused by free-free radiation in the stellar wind. Starting from 1997 or
1998 at the latest, carbon dust grains are responsible for the more and more
dramatic decrease of optical radiation and the growing infrared excess. Its
photometric behavior in 1998 - 1999 mimics the ``red declines'' of R CrB
variables, the amplitude, however, is more extreme than any fading ever
observed in an R CrB star. Evidence is given that a complete dust shell has
formed around V4334 Sgr. It therefore shows similarities with dust-forming
classical novae, although evolving ~20 times more slowly. Its luminosity
increased by a factor 4 between 1996 and 1998. A comparison of time scales of
the final helium flash objects FG Sge, V605 Aql and V4334 Sgr shows that the
observed photometric and spectroscopic features are similar, while V4334 Sgr is
the most rapidly evolving object to date.
