On the Finale forums people didn’t often refer to Rastral sizes, but I notice that here they may be more often used as a measure of stave height than are millimetres. What might be the advantages or disadvantages in using one or the other?
I suppose that over many decades I must have heard librarians and copyists use the term Rastral, but as soon as they noticed my blank look I suspect they would have ‘translated’ either by showing me an example or by some other simple means. Looking at the table on page 483 of Behind Bars I expect I can soon familiarize myself with the Rastral scale. However, long ago I learnt to be wary of specialist jargon that might be confusing when attempting to communicate with the non-specialist – unless it was clearly more accurate and efficient than the lay term.
Is the Rastral scale more accurate and efficient than using millimetres for stave height? (At present I am neutral.)
Punches for plate engraving, dry-transfer sheets nor blank staff paper are infinitely scaleable, so by necessity the sizes got standardized. With digital engraving, this limitation doesn’t exist anymore, so millimeters are more universally applicable.
There’s nothing “better” about using a given Rastral size, compared to using some custom size between two of them – those are just the traditional sizes of the tools that pre-digital engravers had. They are a good place to start, in the absence of any other criterion.
As with metal type – you would have a case full of 12pt and 16pt, with nothing inbetween; but now we can use 13.5pt or whatever you like.
(Rastrum is of course Latin for rake, because it was a rake-like 5-pronged tool used to draw the lines of the staff against a ruler. )
Or your chosen unit of length. I work entirely in points!
I did at one time request to MakeMusic that they add Rastral sizes to the Setup Wizard, but…
Points for me as well! They’re a great consistent unit for small measurements using only integers. Not so great for page sizes though… 
If I work notionally on an A4 page, will Dorico calculate for me the stave size if printed to B4?
I seem to remember being told a year or two ago that all that sort of calculation was very much simpler in Dorico than the convoluted arithmetical exercise required in Finale.
I prefer to work in millimetres, as (at least outside the USA) these are universal units understood by all, including lay people. That said, I can see the attraction of Rastral sizes.
A4 scaled up to B4 is 119%.
If your page size in Layout Options is set to A4, and you print to a B4 piece of paper, then the “page image” – what the music looks like on A4 – is scaled up to fit on B4 (within your defined margins). You can see this by going to Print mode, choosing Printer as a destination, and changing the page size under Page Setup; the preview will change to show you what the music looks like.
I think this is the same as using A4 in Finale and ticking “Fit to page” when printing to B4 paper. Neither program changes the actual layout; they just scale the layout to, well, fit the page.
You’ll note that Rastral sizes correspond to measurements in mm (or your preferred unit). So you can pick a Rastral size for its convenience, and then describe it to others in mm.
In Finale I seem to remember faffing around with the fourth root of 2 – but then that’s near enough the same thing: the fourth root of 2 being approximately 1.19…
Yes, because B sizes are the geometrical mean between two A series, who ratio is √2.
Thank you for the correction: it must be my old age (or something). I’ve now corrected it in my original post.
