kortink@.cs.utwente.nl (John Kortink) (05/20/91)
In article <1991May17.112946.27062@gdt.bath.ac.uk> ma9mgg@gdt.bath.ac.uk (M G Gidley) writes: >This isn't a very technical query but one that has been annoying me. I scanned >a sprite with a 16 grey-scale palette. I then used the Palette utility from >the desktop to make the sprite mono (ie 8 colours black and the others white) >and on the screen it looked ok. However, I then tried to output it to a HPII >laser printer but what I thought was white came out as grey (although a VERY >faint grey. I checked the palette to make sure there was no slight hint of grey >in the 'whites' and all seemed fine. I've tried outputing it through !paint >and Impression (through !PrinterLJ and !PrinterDM) and the results are still >the same. > >If anyone can offer me help I'd be most grateful. > >ma9mgg@uk.ac.bath.gdt It might have to do with the palette definition : Acorn made a mistake here. R,G and B intensities have 8-bit room in palette definitions (i.e. also in sprites), but only the top 4 are used because of the VIDC DACs. Hence 'white' is recorded as R=G=B=&F0, when it should be &FF. Maybe this causes white to come out as a light shade of grey, I had someone complaining about this as Creator did this 'misinterpretation' too, so you'd end up with a, say, TIFF file with light greys instead of whites. Unfortunately, when Acorn finally improve the VIDC, sprites may end up using the full 8 bits, so there's no telling anymore whether to give the RGB values a special 4-bit interpretation or not. John Kortink ------------------------------------------------------------------- Student of Informatics at the University of Twente, The Netherlands NETMAIL : kortink@cs.utwente.nl DISCLAIMER : you know .... "It's a one time thing It just happens Suzanne Vega ('Cracking') a lot" -------------------------------------------------------------------
maumg@warwick.ac.uk (Pop Mobility Freak) (05/21/91)
Dear John,
Sorry to annoy everyone by wasting bandwidth but I cannot seem to mail
John and have a bug report about Creator. So John please could you mail me at
pmf@uk.ac.warwick.cs and I will see if I can reply.
Apologises,
PMF