An advantage of retrieving patent drawings electronically is the ability to manipulate and transfer them. Some patent attorneys paste drawings into opinion letters rather than appending a photocopy. Drawings can also be enlarged and printed for litigation work. Each patent may have multiple drawing sheets, and each drawing sheet may contain five or six figures. Each drawing sheet comprises an individual file, but you can extract individual figures from those files.
All patent drawings are black and white line drawings.
Not all providers furnish separate images and text. Display results in KWIC format to see if you're on target. You may not wish to limit your search to captions just in case numbers are mentioned in the text. Doing so scans the full text, even though your results appear as tables of contents only. Only when you link to the actual text from the table of contents will you be charged.