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From: herbw@midas.STS.TEK.COM (Herb Weiner)
Newsgroups: comp.sys.mac,comp.sys.mac.programmer
Subject: What true color board to purchase (24 bit or 32 bit)?
Keywords: true color board, 32 Bit Quickdraw
Message-ID: <4844@midas.STS.TEK.COM>
Date: 16 Aug 89 19:43:42 GMT
Followup-To: comp.sys.mac
Organization: Tektronix Inc., Beaverton, Or.
Lines: 26


It's time to upgrade my RasterOps Colorboard 64 (24 bit color
but NOT compatible with 32 Bit QuickDraw) to a 32 Bit QuickDraw
compatible board.  The question is, do I need a 32 bit board,
or is a 24 bit board sufficient?

* A 24 bit board does NOT have the 8 bit alpha channel, which
  Apple has not yet defined.  24 bit boards therefore ignore
  the alpha channel in a 32 bit PixMap.
* If I purchase a 32 bit board, what will I need to do (in the
  future) to make use of the 8 bit alpha channel?  Will I need
  any hardware upgrade on the board?  Will I need a firmware
  (ROM) upgrade?  Will I need a different cable or monitor?  Or
  will the alpha channel work as soon as software supports it?
* The two boards I am considering are the RasterOps Colorboard
  264/II (aprox $700 with my developer discount) and the 
  RasterOps Colorboard 232 (aprox $1500 as an upgrade from my
  Colorboard 64).  The Colorboard 232 offers additional video
  options which I am not likely to use.  Therefore, is it worth
  spending an additional $800 for the extra 8 bit alpha channel?
* Are there any other alternatives I should consider?

(I am currently using this board with an AppleColor 13 inch
monitor as a second monitor.)

Herb Weiner (herbw@midas.STS.TEK.COM)