FITS Header Pane

The FITS Header Pane displays the FITS Format header of the current image in a docking pane grid. In addition to viewing the header, you can edit keyword values and search for text strings in the header. Edits appear in the header listing as soon as they are "saved", but they become permanent ONLY after the is saved to a FITS file. See Editing the FITS Header and Related Topics, below, for alternative ways to view and edit the FITS header.

• The FITS Header Pane opens from the Image Window > Edit menu and the button on the Image Tools Toolbar.

Changing Values in the FITS Header

Each header line contains three items: a keyword, its value, and an optional comment. The value itself may be changed using the pane's top-most edit field and button. Double click on the target header value to load it into the text field, make the change, and use the [Save] button to replace the value in the header.

When the FITS Header Pane opens the first time, the top-most text field gives the instruction "Double-click the value to change". This disappears after you double-click on the header.

Procedure:

• Double-click the header line where you want to change the value. The current value is pasted into the top-most edit field.

• Change the text in the edit field.

• Click [Save] to replace the header value with the new text.

Copying the Header using Menu Commands

The grid's popup-menu contains commands for copying the header data to various targets. Right-click the header to open the menu

FITS Header Color Coding

Some header items may not be edited using this method. These disallowed items are shown with a light pink background. For example, the number of columns, indicated by NAXIS1, may not be edited but may be changed using a command like Expand Image.

Keywords Added when Opening the FITS File

When a FITS file is opened, Mira changes or adds some keywords such as BZERO and BITPIX while the image is held in memory. To show the original values from the FITS file, Mira adds four COMMENT keywords at the end of the displayed FITS header (see below). The following four COMMENT lines are added in memory but are removed when the image is saved to a FITS file (note that the COMMENT values depend on the specific image):

COMMENT FITS file opened with SIMPLE = T

COMMENT FITS file opened with BITPIX = 16

COMMENT FITS file opened with BZERO = 32768

COMMENT FITS file opened with BSCALE = 1

Related Topics

FITS Format

FITS Keywords

FITS Header Editor

View and Search FITS Header

Editing the FITS Header

List COMMENT Keywords

History Keywords

LIST WCS KEYWORDS

List Statistics Keywords

Image Information Editor

MIRAPROC Keyword

Modify Keywords

Add Metadata

Mira Pro x64 8.83 User's Guide, Copyright Ⓒ 2026 Mirametrics, Inc. All Rights Reserved.