The Image plot panel

WARNING: The manual is current several versions out of date. While it may still be useful for some users, please refer to the tutorial for the most up-to-date information.

The Image plot panel displays any detector image that RAW is able to read. The image name is shown at the top of the plot, while the x and y axes are in dimensions of pixels. There is no right click menu for this plot, but scrolling with a mouse scroll wheel will zoom in and out. It is possible to display regions where there is no image data, these will show up as a white background (for example, if you zoom out and show negative pixel ranges.

In addition to the plot toolbar buttons shared by all of the plots, the Image plot has the following buttons:

100002010000001800000018B603AD208545D77F_png

Displays the image header. This does not display any information from separate header files, only what is in the image itself.

1000020100000018000000187E6D3770EAA7994B_png

Opens the image display settings dialog described in below.

10000201000000500000001EACBFAAFAC41D2CC1_png

Shows the previous/next image in the same directory as the current image (as sorted by filename, A-Z).

The Image Display Settings dialog

The Image Display Settings dialog lets you change how the image is displayed on the screen. It has three sections, Image parameters, Image scaling, and Colormaps.

Image parameters

There are three slider bars here. The Upper and Lower limit sliders let you set what pixel values in the image correspond to the most extreme values of the color scale chosen. The Brightness color bar does not work at the moment. By default, the upper and lower limit values are automatically set each time an image is loaded into the Image plot panel. However, checking the Lock values checkbox will prevent the current set values from changing. This allows you to scroll through images maintaining constant upper and lower limits.

Image scaling

Image scaling allows you to use a linear or logarithmic (base 10) color scale. The logarithmic scale uses the matplotlib.colors.SymLogNorm function (more available here: https://matplotlib.org/api/colors_api.html), with a linear threshold set at 1. So the image is logarithmic in color display above 1, and linear in color display below 1 (this is so 0 and negative value pixels can be handled).

Colormaps

The colormaps option allows you to change the color scale used to display intensity values in the Image plot. The color maps are those available through matplotlib ( https://matplotlib.org/users/colormaps.html), a limited selection of which are available in RAW: Gray, Heat, Rainbow, Jet (default), Spectral.

Note: Currently there is also a brightness setting, but it does not work properly.