Next: 10. Markers Up: Fitsblink 2.1 user manual Previous: 8. Erasing an image
Subsections

- 9.1 Colors and grey levels
- 9.2 Adjusting grey level mapping

# 9. Image display

## 9.1 Colors and grey levels

When the image is loaded into memory, it is also displayed in an X window. Before or after loading you can choose either grey level or color coded intensity display. You choose the pallete by pressing either Grey or Color button in the image window. If you want to save this setting as a default mode for the next time when you invoke `fitsblink`, go to the Astrometry menu and press the Settings button. Although white stars on black background are ``natural'', you may prefer to set the inverse mode (black stars on white background) or color mode in which you spot nebulosities more easily. If you have only an 8-bit display and you already run some colorful program when you invoke `fitsblink`, the color pallete may be limited.

## 9.2 Adjusting grey level mapping

If you are not happy with color or grey level settings which were set automatically when the image was loaded, you may want to adjust them manually. You can do this by holding the left mouse button on one of the points in the Grey level correction window and dragging it to a desired position. Typically, the two points between which the curve jumps from zero to the maximum value are very close together. For fine adjustment you should zoom the curve by clicking on arrow buttons below the window. Press right mouse button for quick zoom, middle mouse button for moderately quick zoom and left mouse button for slow zoom. Pressing right mouse button on the third arrow is what you usually need.

Next: 10. Markers Up: Fitsblink 2.1 user manual Previous: 8. Erasing an image