Creating a High Resolution Bitmap file for Stamping/Emboss Plates

Is the artwork for making metal plates in zinc, magnesium, copper etc, for letterpress foil blocking?

I never have a need for bitmap files and happlly avoid them. Would need to work at 2540 or 3386 dpi to match vector quality,  files get slow or get errors about too many pixels adn in bitmap mode some important Photoshop tools do nto work..

For flexo or roto gravure printing on plastics we have a very high minimum dot, so will take a gradient or drop shadow and make that bitmap, but only 300 dpi since we do not need a hard edge, just to make a fake stipple dot gradient with spaces in between solid 100 ink rather than screening the ink.

Initially back around 1985 we would get a logo on RC paper or film and scan that at 2400 (as that the setting the scanner had to closest match the the 2540 dpi available at the time). But noone works that way anymore as everyone has vector logos, or on rare occasion we will hand trace that to vector or use image trace.  RIPs are much more powerful nowadays so you do not get crashes, as when for example the L100 was the best expose scanner out there. Bitmap though can cause very slow printing, so that is why we avoid the bitmap format as would cost us more time and less profitable in long run.

If you do not have vectors graphics  resizing will be done via interpolation if you are keeping the print size the same.  Going from 300DPI to 1200DPI is a 1600% increase in the number of Pixels 16x.  Try all the different Interpolation methods on your content see if one works better that the rest. 16x  is quite a large increase in size.   Why do you need 1200DPI?