Originally posted by gokenin I assume that she has a Pentax DSLR? if she does than all she would have to do is pick up any k-mount SLR that Pentax ever made and all her lens will be able to be used. Film is not going away anytime in the near future as there is a growing trend of people using film again not as much as pre-digital but it has increased in popularity as of late. I would guess that if the class is requiring a film SLR then developing the film would also be covered in the course as well.
Not quite true. While dslr lenses will mount on a k-mount film camera, there are at least two potential problems with using a new lens on an old camera.
First, many new lenses (all the DA series lenses), have no aperture ring. This is not a problem on the cameras that used A-series, or later lenses, such as the Program Plus or Super Program, or any of the film autofocus cameras. An older k-mount lens such as the K-1000 (famous as a student camera) or any of the M-series cameras (ME, ME Super, MX, MV, MG, etc.) will have no way to operate the aperture.
There aren't as many different film emulsions to choose from, and fewer retail locations to buy from, but there is still plenty of film available. Kodak has even introduced new emulsions in the last couple of years. Kodak and Fuji still have several color print films to choose from, plus slide film, as well. Kodak and Ilford each have several B & W emulsions.
If you are going to shoot B & W, just make sure that it really is B & W. Kodak and Ilford both make "chromagenic" B & W film that is developed in the same C-41 chemical process that is used for most color negative film. This is useful for those who want to shoot B & W, but can't or don't want to develop their own film. You just take this stuff to Walgreen's or Costco and treat it just like color film. This film is not usually used for film-based photography classes. They usually require students to develop their own film, and traditional B & W, such as Tri-X are considerably easier than C-41.
One notable loss, is Kodachrome. Kodak announced last September that the last run of Kodachrome had been produced and that when it was sold out, it was gone forever. For about the last five years or so, there has been only one lab in the entire world that could process it, Dwayne's in Parsons Kansas. Dwayne's has promised to process any Kodachrome that they receive on or before December 30 (not the 31st, they're closed that day) of 2010. After that, Kodachrome will be completely gone.
The other problem is that DA lenses are designed for the smaller APS-C sensor. When used on a 24 x 36mm frame film camera, severe vignetting may results. Not all lenses will do this, but many will, especially at shorter focal lengths. I have a K10D, with the 18-55mm DA kit lens. I tried it on my SF1 autofocus film camera. The lens functioned perfectly, but at 18mm up to about 30mm, the corners were vignetted completely. Above that focal length, the image filled the frame.
All that being said, the older Pentax cameras can be a joy to use and are available at very reasonable prices. Any lenses that she gets to work with her film camera will work on her dslr. Even screw mount lenses work, with an inexpensive adapter.