Re: Barline scans

[Marnen Laibow-Koser]

Han-Wen Nienhuys wrote:
> Hello,
>
> I had another look at a lilypond print-out locally, and I think that
> with the settings as is, it looks good, not in the least ugly.
>
> *However*
>
> I already discussed some of this with Jan, and we found that printer
> artefacts might also be a factor: Jan's printer doesn't produce even
> output, lines near the right edge being thinner.
>
> In my case (HP Laserjet 2100 @ 1200 dpi), it seems that horizontal
> lines are printed approximately 10% thicker than vertical lines,
> regardless of the method of generation. 

Very interesting.

> I would welcome some data points, so I am attaching a PostScript
> document which prints lines at current bar size (0.19 staff space)
> horizontally and vertically. You can print this out, and scan it back
> in, to determine what kind of bias the printer introduces.  To be sure
> that your scanner does not introduce distortion, it's best to scan it
> twice (once rotated 90 degrees), and compare.  There are two files,
> one uses PostScript lines and one uses rectangeles.

I'll be happy to try this.  I am very curious as to what the results 
will be.

Note that output from other applications, including Finale, appears to 
be quite well-proportioned on this same printer.

[...]
> All the vertical lines appear extremely jagged, suggesting that you
> used an inkjet printer.  

Correct.

> If I measure between the extremes of the
> jaggies, I see 26 to 29px, which is well over the 22px we expect the
> lines to be. 

I did not measure this way; rather, I measured between the straight 
edges, as close as I could judge them, and got measurements that seem to 
match your laser-printer results, so I tend to think my method is sound, 
if slightly less precise.

> For comparison, I put up a fragment of the 2400dpi scan
> of the raster for my printer at 
>
>   http://lilypond.org/~hanwen/raster-scan-0092.jpg
>
> Can you print results on a laser printer before criticizing them?
[...]

I'll try.  I don't have easy access to one right now, though.

I would have just measured from the PDF file, had it not been for John 
Neeman's point that the document might print slightly differently.

Best,
Marnen