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Any favorite PDF viewers (pay or Free) you can recommend that can measure nicely?
Acrobat and PDF-xChange viewer are OK but the measuring ability is horrible.
Depending on the file - you can run the PDF through Ghostview and export as a dxf. However, PDF typically reduces curves and arcs to line segments, so one loses the ability to directly locate the center unless cross marks are built in.
Other than that, GIMP and Photoshop can render the files to bitmaps and there are rulers available in both of those for making measurements in either pixel space or scaled by rulers.
I have used BlueBeam Revu for the past several years and I like it. They do have a free version with limited functionality that I believe can also measure.
The picture shown above is a PDF generated by Creo 3.0. I used the Calibrate and Measure tools in BlueBeam Revu to insert the dimension in red.
Wow this Bluebeam looks really promising! Calibration, precision, YES!!! I will dig into it and see how it works with our processes, but so far its the best viewer I've ever seen. Re-exporting the current PDF is not an option. These are all being auto created by my toolkit, I could easy just create a dxf at the same time but I don't want to have two copies of exports to maintain.
The full version (Pay For) "Revu" is around $250 and it can save everything.
Another feature that I like is that I can filter the markups during printing so that I don't print the notes/measurements unless I want to.