[Qgis-developer] 8-bit colour ramps?

[Barry Rowlingson]

Someone on gis.stackexchange.com:

http://gis.stackexchange.com/questions/29357/how-to-improve-the-display-of-color-images

says, about colour ramps:

"
 but in ArcGIS and QGIS, they don't seem to be easily usable for a
finished product because their complexity causes obvious steps rather
than a smooth gradient. The raster renderer appears to be stuck at an
8-bit palette (only 256 levels), rather than a mathematical transform
involving 24-bit standard RGB or deep 48-bit RGB.
"

 huh? I'm pretty sure the colours in the raster colour map dialog are
24 bit (#abcdef looks like 24 bits to me) so what are they on about?

 Anyone want to authoritatively respond on the site? The poster has
already accepted an answer claiming they can do it with ArcGIS...

Barry