There are several ways to view side-by-side 3D photos.

The easiest way  is  with  3D  prism  type  glasses  (parlor
viewer).  They are purchased with 3D books or from 3D supply
companies that use side-by-side 3D photos.   These  are  not
colored  or  polorized  glasses.   Sometimes  there  is some
magnification for enlargement purposes.  These are the  kind
of  lenses  found  in  parlor  viewers  from the late 1800's
through the early 1900's.  (Many are still around today.)

To "free view", that is, without glasses you  will  need  to
look  at  the  left  picture with the left eye and the right
with the right eye.  Some people can do this just by looking
beyound  the  2 pictures seeing a center 3D image and a left
and right perifieral image also visable thus it will seam as
if  there  are  3 pictures out there with the center looking
correct and in 3D.

There is however, an easier way?  With 3D  pictures  on  the
screen,  position  your  face  about  18" from your computer
screen.  By placing your index fingers pointing  up  against
your  nose,  place your right index finger against the right
side of the end of your nose.  Place your left index finger
against  the left side of the end of your nose.  Close your
left eye.  Looking through  your  right  eye, position  your
right  finger  so  that  it  blocks the left image from your
right eye.  Close your right eye.  Look  through  your  left
eye. Position  your  left finger so that it blocks the right
image from your left eye.  Now open both eyes and look  past
the  image.   The  two images should come together forming a
single 3D view.  You may now be able  to  bring  your  index
fingers  together  in  front of your nose  then  drop  them
down out of view while keeping the  center  3D  view.   Once
this  is  achieved and using your arrow keys, scroll through
all the photos.