Path: utzoo!news-server.csri.toronto.edu!bonnie.concordia.ca!ccu.umanitoba.ca!herald.usask.ca!telepro!tptbbs!James_Hastings-Trew From: James_Hastings-Trew@tptbbs.UUCP (James Hastings-Trew) Newsgroups: comp.sys.amiga.graphics Subject: Greyscales on Amiga Message-ID: Date: 12 Mar 91 23:47:41 GMT Organization: TelePro Technologies Lines: 25 In a message dated Tue 12 Mar 91 04:50, Harvey_taylor@mindlink.uucp (harvey wrote: H> Background: I want to display some large 256 level greyscale H> video samples. The standard Amiga will output only 16 levels. H> So, I am trying to figure out the best way to increase the number of H> greyscale levels viewable on the (my) Amiga. So far the candidates H> are: H> 1) Dithering H> 2) GreyScale to HAM [SHAM, SHAMM, Dynamic whatever] H> 3) A colour board A 24 bit colour card should be able to give you a true 256 grey scale picture. Other than than, you best bet is dithering - HAM and Dynamic modes don't alter the palette available, so still only have 16 greys to work with in those modes. The Art Department does a very nice job of converting 256 greyscale images to 16 greys with Floyd-Steinberg dithering. I daresay at hi-res interlace, the results would be indistinguishable from real 256 grey once you get it into video.