Quote - in these matters, SOP is to search poser forum, user bagginsbill.  docs re: tonemapping in poser 8 are not in abundance, but try these two:

http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2778431&page=23#message_3572246

http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2778431&page=23#message_3572198

maybe bill or others have done the curves for tone-mapping with variable gains to emulate GC curve, and have found such empirical curve-fitting to be unsatisfactory.  it may be necessary to purchase poserpro if GC is desired and tonemapping/gain curves can't be adjusted sufficiently.

Well, discussions on here and doing a search for tone-mapping has produced the usual confusion. It's a bit like the discussion of GC vs corrected-sRGB in certain conditions: it depends.
So, I save up my shekels (150 of them for the Base sidegrade) and purchase PP for the GC capability, or just continue to GC my material and hope that maybe someone at SM might see fit to include GC in Poser 9.

Think that about sums it up.

And I don't think anyone has the answer why GC wasn't included in 8. Or if they do, it's very hush-hush and not for the common herd to know.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand] 

Metaphor of Chooks