"The image resolution of a JPEG/TIFF image saved from SolidWorks is dependent on the screen resolution (within Windows Display Properties or the graphics card settings). Thus minimizing the SolidWorks screen or maximizing it will give a different display resolution, although the DPI settings will remain constant (since this is determined by the Windows/GPU dpi setting)."
The following are some examples of different settings and their resultant output.
The following is the same defaults, just with SolidWorks set to Full Screen and drawing area maximized vs. the display:
Notice the image is larger and the fine print is now legible.
The result of just modifying the compression to HIGH is:
Here is the resultant title block at 1200 DPI, actually scaled DOWN to fit.
It is very easy to see the clarity difference. You need to consider the file size and generation time if you are going to batch print a lot of drawings. You can find a happy medium if you play with the DPI setting vs. the end quality you need. The two drawings that generated the title blocks above had the following end file size: