Plain TeX magnifications

Question

Can I use a magnification like \magnification=2700 in TeX? Or is it restricted to multiples of 500 like \magstephalf, \magstep1 and so forth?

Answer 1

Yes you can use any number, although note the magsteps are based on powers of 1.2 not multiples of 500:

\def\magstephalf{1095 }
\def\magstep#1{\ifcase#1 \@m\or 1200\or 1440\or 1728\or 2074\or 2488\fi\relax}

\magstephalf= $\sqrt{1.2}$ , \magstep2=${1.2}^2$ and so forth.

The reason for sticking to known sizes originally is it avoids needing to generate the bitmaps at non standard sizes, but these days you are probably using scalable type1 versions of the fonts and even if not, you can probably afford the disk space.