When using the BIRT Reporting facilities to generate PPT reports, I consistently have quality issues with the molecule images reported.
They are setup using Dynamic Images, and the "Data to Report" node I have enabled custom scaling to 1000 x 1000 and it still doesnt give crisp images of molecules. They can be quite difficult to visualise on an overhead projector.
I tried changing the renderer from Marvin to Indigo/CDK etc, and to SVG without success.
But, I have just had a breakthrough and found a solution. In case others want the answer..
I was using Marvin renderer anways, but what I found is in the KNIME preferences, under KNIME, and then Marvin is where you can tweak the Marvin renderer in many different ways.
Simply increasing bond thickness and atom label size did the trick.
There are loads of other options in there, but didnt need to play around with them.