RSS/Atom feed Twitter
Site is read-only, email is disabled
  1. Chat
  2. Useful links
  3. Polls

Featured content

Graypoint and gamma

This discussion is connected to the gimp-user-list.gnome.org mailing list which is provided by the GIMP developers and not related to gimpusers.com.

This is a read-only list on gimpusers.com so this discussion thread is read-only, too.

1 of 1 message available
Toggle history

Please log in to manage your subscriptions.
Graypoint and gamma Enno Fennema 19 Mar 13:35
Enno Fennema
2009-03-19 13:35:04 UTC (almost 16 years ago)

Graypoint and gamma

I fail to understand the relationship between Gamma and the value of the Graypoint as shown in the Adjust Color Levels tool.

Leaving the input and output ranges from 0 to 255 and setting gamma = 2.0 I expected the midpoint triangle to move to about 64. Input 0.5 to the power gamma is 0.25 (that is about 64 in 0 to 255 speak).

In fact the graypoint triangle is showing approx. 0.33 (or 85).

Would be grateful if someone could explain what is going on.

Thanks, Enno