How to

1. How to set the same brighness/contrast display on all open images in ImageJ?

Activate one of the images and open the B&C-Adjuster from the menu Image>Adjust>Brightness/Contrast.... Use the minimum and maximum sliders to adjust the contrast/brightness. Press the set-button. Check the Propagate to all other open images checkbox and press the ok-button.

2. How to annotate movies with arrows in ImageJ/FIJI?

Install the Image, Stack and Timelapse Arrow Labelling toolset. Download the toolset and copy the file into the folder macros/toolsets of your ImageJ/FIJI installation. Select the toolset from the >> button of the ImageJ-launcher window. Read the documentation of the toolset.

3. How to get a stack from side to side instead of top-down?

Use the command from the menu Image›Stacks›Reslice [/].... Read the documentation of the command.

4. How to make "Rotated Rectangle" rois without changing the length while rotating?

Make a rotated rectangle with the desired size and any angle with the x-axis, then use the Selection Rotator to rotate the rectangle to the desired angle while keeping its length and width constant.