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From: drtiller@uokmax.ecn.uoknor.edu (Donald Richard Tillery Jr)
Newsgroups: comp.sys.amiga
Subject: Re: 24 bit color boards
Message-ID: <1990Dec4.061416.16472@uokmax.ecn.uoknor.edu>
Date: 4 Dec 90 06:14:16 GMT
References: <6015@crash.cts.com> <1990Dec4.013744.10286@ncsuvx.ncsu.edu>
Organization: Engineering Computer Network, University of Oklahoma, Norman, OK
Lines: 57

In an article by: bobl@pro-graphics.cts.com (Bob Lindabury, SysAdmin) writes:

>>  Kent is correct. The HAM-E and DCTV are =NOT= 24 bit frame buffers
>> or boards.  They get their color information from lookup tables or
>> some such thing.  Animation with the HAM-E can only be done by flipping
>> full pages, unless you count writing your own software to create
>> animations and such.  Don't be fooled by crafty advertising.  If you
>> want true 24-bit, you'd best get a toaster or Firecracker. --Bob
>
>Well now. Normally, I try to be reasonable when people make honest
>mistakes. When, on the other hand, someone acts like they know 
>it all, when they clearly know nothing (or perhaps slightly less, 
>as in this case), I tend to get a little sweaty.
>
>Not in any particular order, but: The Firecracker, as stated, 
>is a true 24 bit board. At least you got _one_ thing right. The 
>toaster, in sharp contrast to the publicity, is not a 24 bit 
>board, as NTSC composite won't modulate to 24 bits precision 
>in any case. As soon as you go composite (which the toaster always 
>is) you don't have 24 bits. Likewise for DCTV - technically. 

I think the point is that internally the image is represented by 24 bits.
Whether or not composite can do this image justice is not debatable (it
can't).  The thing is that the image presented for video recording (which is
what the composite is for and what even an RGB signal must become to be
recorded) is the best it can be when it comes from a 24 bit source.  Anyone
who goes composite (from RGB or directly) knows this.  

I have to agree with Kent that that means that DCTV is indeed 24 bits (albeit
an unorthodox output method may further degrade the quality-I haven't seen it
yet so I can't vouch for that) because it creates such a signal.  The composite
conversion is where the information is lost and this is in no way reflecitve
of DCTV or it's image resolution.  It is indicative of a poor video method.

[More about HAM-E deleted]

>Ben Williams, for Black Belt Systems   <76004.1771@compuserve.com>
>December 2nd, 1990, in response to a quote forwarded from comp.sys.amiga
>[ Please email replies to Ben, not me!  - kev]
>

In all this discussion of 24 bit boards and the HAM-E, I'd just like to
comment by saying that in spite of the fact that the HAM-E board has an
RGB output, it CANNOT COMPARE to the quality of the Toaster's video.  Further,
the Toaster's output is _slightlty_ worse than the Firecracker.  I had the
opportunity to view all three side-by-side on several of my own 24 bit RGB
ray-traces and if HAM is a 5, HAM-E is a 6, the Toaster is an 8 and the
Firecracker is a 9 (still want 24 bit non-interlace display).  

The lack of colors and lower resolution meant the picture was not even in
the same ballpark as the Toaster and the Firecracker (and judging by the
RGB 24 bit specs, the ColorBurst).  The dithering was not bad but it didn't
help to overcome the VERY evident fringing.  I'll spend the extra hundred for
ColorBurst when it comes out.

Rick Tillery
(drtiller@uokmax.ecn.uoknor.edu)