[OS X TeX] bizarre preview difference for TeXshop and Adobe Acrobat

[Ross Moore]

Hi Will,

On 19/11/2009, at 6:01 AM, William Adams wrote:

> I'm trying to get a rule snugged up against the top of the page.
>
> Typesetting the following and viewing it at an 875% magnification  
> in TeXshop 2.26 running on Mac OS X 10.5.8 looks correct:
>
> \documentclass{minimal}
> \usepackage[margin=0bp,paperwidth=174pt,paperheight=36pt]{geometry}
> \begin{document}%
> \newlength{\textlineheight}%
> \newsavebox{\scratch}%
> \setbox\scratch=\vtop{\strut}%
> \textlineheight=\ht\scratch%
> \noindent\begin{picture}(0,0)\put(0,0)%
> {\rule[\textlineheight]{174pt}{1pt}}%
> \end{picture}%
> Test\begin{picture}(0,0)\put(0,0)%
> {\rule{1in}{1bp}}%
> \end{picture}%
> Test\end{document}
>
> But then when viewing it in Adobe Acrobat there's an obvious gap  
> and when measuring it in Adobe Illustrator or using PitStop the  
> centerline of the rule is 1.096 PostScript Points from the top of  
> the page.
>
> It looks right in Preview.app as well.

In Preview.app or in TeXshop's previewer?
For me, Preview gives the gap, just as Adobe does.
But TeXshop's previewer has no gap (except at small
sizes where it will be an anti-aliasing artifact).


But what surprises me even more is these different
applications' ideas of what is 100% .
To match Adobe Reader's displayed size (supposedly
at 100%) I have to scale to 160% in TeXshop or Preview.
This is a pretty accurate comparison --- the attached
image shows it as 600 : 960.

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>
> Anyone have any suggestions?

No. Just more questions.

Ahah. Adobe Reader has a Preference for "Resolution"
of  "Use System setting": 115 pixels per inch.

Now 115/72 = 1.597222222222222
which looks like my 1.6 factor.

But you would think from the name that this would
scale the other way. Can someone explain?


>
> William
>


Cheers,

	Ross

> -- 
> William Adams
> senior graphic designer
> Fry Communications
> Sphinx of black quartz, judge my vow.



------------------------------------------------------------------------
Ross Moore                                       ross at maths.mq.edu.au
Mathematics Department                           office: E7A-419
Macquarie University                             tel: +61 (0)2 9850 8955
Sydney, Australia  2109                          fax: +61 (0)2 9850 8114
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