With the default image quality setting, the QTVR export format produces
images that are unnecessarily large. QTVR image file size can be
reduced without appreciable loss of image quality by reducing the QTVR
The QTVR export format produces images that are much larger than the
images produced by the JPEG export format when the same quality settings
are used on the QTVR and JPEG Settings dialog boxes. For example, setting
quality to 75 produces QTVR files that are about twice the size of the
corresponding JPEG files.
The quality scales should behave in similar ways for all export
formats. If someone understands how the image quality setting works
for one format, that knowledge should (if possible) carry over to other
formats. In particular, QTVR images that use JPEG compression should
behave similarly to JPEG images.