I am unable to get a high resolution export.
Use PDF Creator, an open source print driver which exports in many formats. I got a 6600 px image from this.
1. In CC3 set Tools >> Options Resolution Divided by to 2.
2. Print >> Set the printer to PDF Creator.
3. Click Properties >> Advanced, set the resolution 1200dpi, and the paper size to letter.
5. When you see the PDF Creator dialog, click Options and choose PNG, set the resolution to 600 dpi.
6. Click Save, pull down the file type to be PNG and and type a file name.
It might vary from drawing to drawing and system to system, but it's seems to give good high res results.
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