PDF to Tiff in Adobe Acrobat Standard or Pro

Converting a PDF to TIFF in Adobe Acrobat and reducing size (when normal convert still isn’t enough)
(Optional) Isolate the files you want to convert
Document | Extract Pages

Saving the file and reducing resolution
File | Save As
save as type, change to Tiff, then click Settings button

Colorspace – Monochrome (or grayscale.. Monochrome makes it 1 bpp and half the size of grayscale. Grayscale makes it 8 bpp.
Resolution – changing from 300 to 150 reduces size even more (and moves faster).

You can play with other options, but this change only makes it much better.