Way to ftell within a Tiff object?

I'm writing a function to quickly identify the number of IFDs in multiple Tiffs that contain thousands of IFDs. In most cases for our usage, the data in each file is structured the same so we could save a lot of time just by comparing to the earlier file, which I could do using basic file I/O rather than using the Tiff class, which has to jump from each IFD to access the later ones and is thus slower. Is there a way to get the current file position for a Tiff object, or to get access to the file identifier that the Tiff object is using?