set_character_size and XYOUTS

[Declan Vogt <drv102(at)ohm.york.ac.uk>]

Hi,

;I'm missing something. I am creating a plot area and setting a
character
;size, using

	window, xsize=400,ysize=720
	device, set_character_size=[15,20]
	!p.charsize=1.0

;then plotting some data in 3 graphs:
	!p.multi=[0,1,3]
	plot, findgen(100)
	plot, findgen(100)
	plot, findgen(100)

;then writing some text using XYOUTS:
	xyouts, 0.5, 0.1, 'Hello', /normal

All my graphs look the way I want them to look, nicely scaled for the
large plot area, with legible axes. But the text I am writing over the
top is very much larger. XYOUTS takes charsize, but I find I have to set
it to about 0.6 to get the text to be the same size, which I don't
understand: surely if the character size is set, then XYOUTS should get
its character size from that too?

All help very much appreciated,

Declan

(I'm using IDL 5.1 running under Windows NT4.0 on an 8 bit display, if
that makes any difference)