Change figure caption name only in one figure, not all

Question

I saw here Change caption name of figures , by

\renewcommand{\figurename}{Fig.}

but if you do that, it changes all of the figures captions. How to change only some of them?

but I have 3 figures, I want default caption for figure 1 and 3, but Photo caption for figure 2.

so it should be like, Figure 1, Photo 1, Figure 2.

\begin{figure} 
      ...
      \caption{This is a figure.}
\end{figure}


\begin{figure} 
       ....
       \caption{This is a photo.}
\end{figure}


\begin{figure}
       ...
       \caption{This is a figure.}
\end{figure}

Answer 1

do it inside the environment, then it is local:

\begin{figure} 
   \renewcommand\figurename{Fig.}
       ....
       \caption{This is a photo.}
\end{figure}

Answer 2

The numbering showed in your question suggest that you want independent counters for photos and pictures, so it seems that you want a new independent floating object.

Using the newfloat package you can easily define this new type of float object for your photos:

\documentclass{article}
\usepackage{newfloat}

\DeclareFloatingEnvironment[fileext=lop]{photo}

\begin{document}

\begin{figure}
\centering
A
\caption{This is a figure.}
\end{figure}


\begin{photo} 
\centering
B
\caption{This is a photo.}
\end{photo}


\begin{figure}
\centering
C
\caption{This is a figure.}
\end{figure}

\end{document}