bad image export from Premiere

I tried exporting a jpg then a tiff file from Adobe Premiere for a screen capture.  I’ve never noticed a problem before, but maybe I just never exported a screen capture that included text.  The export files came out horribly pixilated. I tried a few different adjustments, but it didn’t work. I never figured out the problem, I just took a screen capture of the image using my Mac (Shft+Cmnd+4). Easy fix, though not the preferred.