🚀 go-pugleaf

blacka@logica.co.uk wrote:

>However, I discovered that the 3.1 driver does not support
>colour in resolutions above 180x180.  I appreciate that high
>resolution colour printing is not for those in a hurry, but
>on occasions one is prepared  to wait.

>Is this a restriction on the way that the Acorn driver
>software works or can it be sorted out by adjusting the
>printer config file.

If you haven't read it already, read what I wrote on App2 in the
Printers.Epson.Read_Me file (assuming you're using the Epson.LQ-860 file as
recommended for the Star XB24-10 in the Star.Read_Me file). The
Epson.Read_Me file entry for the Epson.LQ-860 says:

"... Colour is available for the non interlaced graphics resolutions ie.
180 by 180 DPI or lower (for an explanation as to why colour is not enabled
for interlace printouts, see the comments above about the Epson.JX-80
file). ..."

The entry for the Epson.JX-80 says:

"The "Epson.JX-80" printer definition file is the same as the "Epson.FX-80"
file, except that it uses colour for non interlaced graphics printouts ie.
120 by 72 DPI or lower. There are two reasons for this. Firstly, interlaced
colour printing would involve an excessively large number of  print head
passes (8, 12, 16 or 24) over the same line on the paper. Secondly, on the
second or subsequent interlace passes, the light ribbon colours (eg. yellow)
would be printing on top of dark colours already on the paper. This causes
contamination of the lighter ribbon colour and seriously reduces usable
ribbon life - unless you are happy with muddy yellows."

This explains why I didn't put colour interlaced resolutions in. In a school
environment (and many others), it just isn't appropriate as it takes forever
and destroys the ribbon in no time at all (and schools can't afford to waste
consumables like that). Kids being kids, it is very likely that left to
their own devices they'll select what appears to them to be the best
resolution ie. the highest.

As to what you can do about it, all you need to do is play around with
!PrintEdit for 10 minutes. I did actually try 360 by 360 colour on a Star
LC24-200, starting with a brand new ribbon. It took FOREVER to print (16
head passes per line) and the paper was a soggy mess afterwards. The 180 by
180 printout of the same picture actually looked better. (There was a review
of colour dot matrix printers in Acorn User about 18 months to 2 years ago
that said the same thing ie. 180 by 180 looked better than 360 by 360.) On
top of this, when I tried it the ribbon needed changing after just one page
of 360 by 360 - the yellow just wasn't yellow anymore after over-printing so
much on darker colours. I stand by my decision not to make interlaced colour
resolutions available in the supplied printer definition files. If you want
to add it yourself, go ahead. !PrintEdit is all you need.

Owen.