I have a few pages with two images. I want these images centered on the page.
I tried with this
\newpage \vspace*{\fill}
\begin{figure}[H] \centering
\subfloat[Text]
{\includegraphics[height=18cm, width=0.8\textwidth, keepaspectratio]{figure/...}}
\hspace{2mm}
\subfloat[Text]
{\includegraphics[height=18cm, width=0.8\textwidth, keepaspectratio]{figure/...}}
\caption[Short-Text]{Long-Text}
\end{figure}
\vspace*{\fill} \newpage
but I don't like the result. There isn't the same space above and below the image.
The document class I'm using is book
Best Answer
Here is a minimal example which compares your approach (the vertical fills, which are ok IMHO) with the approach I proposed in a comment (to put it all inside a tikz node which is drawn at the absolute center of the page).
The difference in the output is minimal. You have to compile twice to allow TikZ to place properly the overlay node:
The one on the right (which uses TikZ) appears to be a bit raised but, as said, the difference is minimal. Perhaps in your actual use case it is more visible.