minard@extro.ucc.su.oz (Robert Minard) (09/06/89)
Does anyone know of a graphics card and software which will display 256 colours under Microsoft Windows/286 and Windows/386? We have been looking, and so far all of the cards we have seen which have hardware support for 256 colours at 640x480 and 800x600 only support 16 colours in their Windows drivers. Our application involves the display of grey-scale images, so if you know of any software which can do this, we would like to hear about it.
rogerson@PEDEV.Columbia.NCR.COM (Dale Rogerson) (09/07/89)
In article <593@extro.ucc.su.oz> minard@extro.ucc.su.oz (Robert Minard) writes: > > Does anyone know of a graphics card and software which will >display 256 colours under Microsoft Windows/286 and Windows/386? We >have been looking, and so far all of the cards we have seen >which have hardware support for 256 colours at 640x480 and 800x600 >only support 16 colours in their Windows drivers. I talked to Headland (Video-7) on the phone about their VRAM VGA card. They said that they had 256 color drivers for the 640x480 and 640x400 modes. However, they did not have 256 color drivers for the 800x600 modes. They said that it would be too slow. The Fastwrite VGA card also had drivers for the 640x4?0x256 modes. These drivers are for both Windows/286 and Windows/386. They do not yet have 256 color drivers for OS/2. > Our application involves the display of grey-scale images, I have heard that VGA cards will not display 256 colors of grey due to the way the bits were divided between red, green, and blue. Anyone know? Please, post any information you get. I am sure there is plenty of interest in this subject. "Dreaming of 386 v3.0 at 1024x768 with 256 out of 256k for only 1k." -----Dale Rogerson-----
mcdonald@uxe.cso.uiuc.edu (09/08/89)
VGA cards and clones, including 600x800 ones, will only display a 64 level gray scale. This is because the DAC's are only 6 bit. HOWEVER, if you really need a 256 level gray scale it relatively easy to make a cable that will convert 256 colors into 256 gray levels. It just requires some hardware hasking abilities. Doug McDonald
kensy@microsoft.UUCP (Ken Sykes) (09/09/89)
In article <2697@PEDEV.Columbia.NCR.COM> rogerson@PEDEV.Columbia.NCR.COM (Dale Rogerson) writes: > I have heard that VGA cards will not display 256 colors of grey due > to the way the bits were divided between red, green, and blue. Anyone > know? > > "Dreaming of 386 v3.0 at 1024x768 with 256 out of 256k for only 1k." > -----Dale > Rogerson----- VGAs use 6-bit DACs, so only 64 gray scale levels are available. This is also the reason you have 256K colors instead of full color. --Ken Sykes Standard disclaimer? But of course!
richg@blake.acs.washington.edu (Richard Goldfinder) (09/11/89)
While there is a limit of 64 pure greys (R=G=B) on a VGA, there are color maps (palettes) that can simulate 256 colors. One is the "Peterson-Vigneau Pseudo-Grey Sequence". An inverted form can be found in the ALTERN.MAP file included with FRACTINT 9.x (perhaps 8.x too?), probably elsewhere. --Richard
ppa@hpldola.HP.COM (Paul P. Austgen) (09/15/89)
I have a Paradise Professional that has a driver for 256 colors and Windows 286.
rogerson@PEDEV.Columbia.NCR.COM (Dale Rogerson) (09/16/89)
In article <3230005@hpldola.HP.COM> ppa@hpldola.HP.COM (Paul P. Austgen) writes: >I have a Paradise Professional that has a driver for 256 colors >and Windows 286. Yes, the Video 7 controllers have 256 color drivers for Windows 286/386 in the 640x480 mode. However, they do not have drivers for the 800x60256 mode! Does the Paradise Prof have drivers for this mode? And for Windows 386? I would really like to know since I am about tbuy a Super VGGA card. -----Dale Rogerson-----
ppa@hpldola.HP.COM (Paul P. Austgen) (09/19/89)
> In article <3230005@hpldola.HP.COM> ppa@hpldola.HP.COM (Paul P. Austgen) writes: > >I have a Paradise Professional that has a driver for 256 colors > >and Windows 286. > > Yes, the Video 7 controllers have 256 color drivers for Windows 286/386 in the > 640x480 mode. However, they do not have drivers for the 800x60256 mode! > Does the Paradise Prof have drivers for this mode? And for Windows 386? > > I would really like to know since I am about tbuy a Super VGGA card. > > -----Dale > Rogerson----- > ---------- My product is at least six months old, so I don't know what they have available now, but they have an 800 X 600 16 color driver. I don't know what you mean by 800X60256. I don't know about the 386. The referrence is to Windows Version 2, which I believe is know as Windows 286. Paul