How to output files to another directory (Poppler - pdftotext)

I have a directory with a very large number of PDFs that I am converting to *.txt documents with Poppler pdftotext. I have the following command that does the conversion of all the files. for f in *.pdf; do pdftotext $f; done The PDFs are on an external storage device without any additional space. How can I redirect the output to a different directory? That is, when each PDF is converted, it is written to another location rather than the same directory as the PDF.