Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!asuvax!ncar!csn!kessner!chris
From: chris@kessner.denver.co.us (Chris Hanson)
Newsgroups: comp.sys.amiga.graphics
Subject: Re: How to increase grayscale levels?
Keywords: HAM-E, Greyscales, Dithering.
Message-ID: <1991Mar12.034220.385@kessner.denver.co.us>
Date: 12 Mar 91 03:42:20 GMT
References: <5083@mindlink.UUCP>
Reply-To: chris@kessner.denver.co.us (Chris Hanson [Lord Xenon])
Organization: Kessner, Inc
Lines: 45

In article <5083@mindlink.UUCP> Harvey_Taylor@mindlink.UUCP (Harvey Taylor) writes:
>    Background: I want to display some large 256 level greyscale
> video samples. The standard Amiga will output only 16 levels.
>
>    So, I am trying to figure out the best way to increase the number of
> greyscale levels viewable on the (my) Amiga. So far the candidates are:
>
>    1) Dithering

  This should help some. I don't know if you'll get 256 grey-levels, but it's
worth a try. Will look very grainy.

>    2) GreyScale to HAM  [SHAM, SHAMM, Dynamic whatever]

  Won't help. HAM and SHAM (And the dynamic-doodads) all have the same number
of gun intensity levels as the normal display modes.

>    3) A colour board
  
Now this WILL get you somewhere. 

>    What greyscales do the popular 24 bit boards put out?
>    (ie. DCTV, ColorBurst, HAM-E, A2140, Firecracker 24)
>    -het

   Well, my experience tells me that DCTV, ColorBusrt, A2410, and FireCracker,
all being 24-bit display boards, can give you 256 gun-intensities, and
therefore 256 greyscales. HAM-E is a palette-based display. It allows you to
display any 256 colors out of 16 million. It can also just as easily display
256 greyscales. It has the added advantage of color-cycling, if you should
so need it.

> "The ghost of electricity howls through the bones of her face"
>                                                    - Visions of Johanna

  Nice quote.

>      Harvey Taylor      Meta Media Productions
>      uunet!van-bc!rsoft!mindlink!Harvey_Taylor
>               a186@mindlink.UUCP

   Chris - Xenon
#define chris Chris_Hanson|Lord_Xenon|Kelson_Haldane
I work, but you don't know who I work for. And this isn't their machine.
I'm chris@kessner.denver.co.us, xenon@tcr.UUCP, and chanson@isis.cs.du.edu