19 " Artar, (about 481 mm), the 450 fugi C (compact) tiny little lens, the 355 G Claron, these all cover at infinity and can do group portraits as well as head shots and can be used on larger formats and smaller...

however, as it has been mentioned... think 1:1, for portraits, head and shoulders etc. the lens does not have to cover at infinity, this gives you lots of possibilities......move the camera closer and pull the bellows, a lot of lenses cover...some of the process lenses i.e. nikor 360 mm and ronar 360 will cover, when the bellows are pulled...they will cover 16 x 20 at one to one!

I would like but do not own yet the fugi 600 mm (compact) it covers at infinity...

the nice thing about 11 x 14 for head shots is
it is the SMALLEST format you can use to photograph the human head at a one to one ratio....

makes a great and most impressive contact print portrait and I feel is unsurpassed for detail using the modern lenses like the fugi and the clarons and various process lenses, taking advantage of the film format and the ability of the lens to show sharp detail.....you need lots of light........