Removal of background in GIMP (single color background)

To remove background of single color in GIMP:

1. Select region by color
2. Click the background
3. Select "Free select tool" and "subtract from the current selection" if there is any wrong region being selected
4. Layer - Transparency - Add alpha channel
5. Edit - Clear
6. Save image using .png or other formats supports transparency.

Rescale Z value in Gwyddion

For comparing roughness of different surfaces, I used Gwyddion for post processed of data files retrieved from AFM. To make the Z scale the same:

*For example, default maximum height of data is 300nm and I want to scale to 600nm.

2D images:
Icon: Tools - Stretch color range to part of data - Explicitly set fixed color range
Changing the Maximum to 600 nm


3D images:
Open data files (in 2D view default)
Icon: View - Display a 3D view of data - Show full controls
Change the "Value scale" to 0.5 (300/600)

Correct number of graphic when refering in the text

Wrong

\section{A}
text text

\begin{figure}
\caption{1}
\end{figure}

\begin{figure}
......
\label{fig2}
\caption{2}
......
\end{figure}
 (This will label the contents such as section or the figure before so that the wrong number will keep showing up)



Correct:
\caption{2}
\label{fig2}