There are several ways to open this editor on a .log file. As stated above, the editor is opened automatically when you run GrainSpotter if you have the appropriate preference set. Double clicking a .log file in the Navigator should open it by default. If instead you right click on the .log file in the Navigator, then you can choose which editor to open it with. Fable remembers the choice, so if you previously opened it with the Text Editor, then it will continue to open it with that editor when you double click until you explicitly choose another editor by right clicking. You can also use the GrainSpotter menu at the top and choose "Open .log file". And you can use Open on the File menu. It should be possible to open files that are not in Fable projects (and hence not shown in the Navigator) as well as files that are in Fable projects.
In the event you would like to modify the file contents, you can do that in the Text page. If you type Ctrl-S or use File -> Save or "Save As" while that page is active, then it will save your changes. You can also open the File with the Text Editor, rather than the Log File Editor and the behavior is then like editing any other text file.
The Log File Editor should notice if the file is changed externally to Fable or internally by running GrainSpotter again and then prompt you to use the new version or not. The Text Editor page may use the new version automatically, however. If you have multiple editors open on a file, they should all notice if it is saved in one of them and also if it is changed outside of Fable.
For .log files which are in Fable projects and hence appear in the Navigator, the editors open when Fable is closed should be displayed again when Fable is restarted.
The Summary page shows a short summary of the results including the number of grains found, the average and maximum meanIA, the grain with the maximum meanIA, and how many g-vectors were found of the expected g-vectors. This is typically the page you want when you are varying GrainSpotter parameters to find the best ones.
The context menu shown, which has a Refresh item, comes from right-clicking the page.
The Table page shows the found grains in a table form. You can expand and contract items in the table as you like.
The context menu shown, which has Collapse and Expand items, comes from right-clicking the page. Each item expands or contracts the table one level.
The Text page shows the .log file as text and operates like the Text Editor. If the .log file is saved, it is saved from the embedded Text Editor on this page.
The context menu shown is the context menu for the Text Editor. You can find other options by clicking or right-clicking in the margins.
This is a short summary of the items found in the GrainSpotter .log file. For more information, see the GrainSpotter manual and other documentation.