I have a somewhat difficult graphics job to do in collaboration with another graphic artist who is using Corel Draw X3. I am using Inkscape as one of several tools to make up for some deficiencies in Corel Draw. One problem that Corel Draw has and that Inkscape shares (as far as I can tell, correct me if I am wrong) is that it is not very good at putting text on a curve. It can arrange the letters appropriately, and turn them to various angles so that the baseline of a character is tangent to the curve. What it cannot do is bend the characters to make them precisely follow the curve. This is not a huge problem for ordinary text fonts, but it is a severe limitation for some decorative dingbat fonts. Some of these fonts have characters that may have a width that is 10 times the height. To make these fit well on a curved object like a circle, they must bend to fit.
Corel has another tool that can bend font characters around a curve - paint Shop Pro. Unfortunately, even several years after absorbing Jasc and taking over Paint Shop Pro, Corel's programmers have not made it possible to export vector drawings from Paint Shop Pro to Corel Draw. Only bitmaps can move from Paint Shop Pro to Corel Draw. In order to move my curved characters from Paint Shop Pro to Corel Draw, I must trace them into vectors. The problem here is that Corel Draw's trace is terrible.
Enter Inkscape - Inkscape's trace is MUCH, MUCH better that Corel's.
I export the drawings from Paint Shop Pro as 1200 pixels/inch PNG bitmaps and import them into Inkscape. Then I trace them. The traces are PERFECT (almost). Corel Draw should cringe with embarrassment.
There is only one problem. Inkscape thinkks that the PNG bitmaps are done at 90 pixels/inch and produces traces that are exactly 13-1/3 times too large. How can I convince Inkscape that these are 1200 pixels/inch bitmaps so that the traces come out the right size?