8.6.1 Choosing a graphics format for WinHelp
The format WinHelp likes best is WMF, which can contain both vector and bitmap elements. For screenshots, use the same resolution at which they were taken, 96DPI; more or less will result in unreadable text.
If your graphics are in a vector format, the WMF equivalents that Mif2Go produces by default as part of the conversion render better than BMP graphics. For example, using WMF instead of BMP can make the difference between readable and not for text on a flow chart. And WMF gives the best display, by far, for graphics to which you have added callouts.
However, WMF graphics can cause serious problems for users on Windows 9x or Windows ME systems; see §8.6.2 Avoiding the GDI resource leak.
If your graphics are in a bitmap format (other than BMP) and you convert them outside of Mif2Go, convert to BMP and let Mif2Go wrap the images in WMF code; see §5.7.2.3 Using third-party graphics converters. Use 256-color BMPs, no higher (no 16-bit or 24-bit BMP images).
For non-Windows WinHelp, created via Altura on Macintosh or Bristol HyperHelp on UNIX, only BMP is supported; see §8.2.7 Accommodating platform differences.
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