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How Shift Lenses Change your Life
be true for any "old" mount with manual aperture control, because it would take Rube Goldberg
hardware to translate the mechanical movement at the mount to movement at the aperture, when half the
lens moves up and down.
You will be paying quite a bit extra, both for the optics that make a larger, shift-able image, and the
hardware on the lens that let you move the glass up and down. Even then, the lens will probably have a
smaller maximum aperture than you'd expect. For instance, a Canon 24mm/2.8 is about $500 while the
shifting 24mm/3.5 is more like $1200 on the street. If its any consolation, the makers are probably losing
money on every one they make due to the low volume of production. You'll see all three Canon TS-E
lenses for the same price, even with their vastly different optics, because Canon is offering them to
complete its lineup, and not attempting to price them to recoup their cost.
Tele-Converters
A tele-converter (TC) is a lens group that attaches between your objective lens and camera body. They
typically magnify the image size by a factor of 1.4x, 1.5x, 2x, or 3x. TC's also (sadly) increase your fstop
by the same factor. Generally any older TC or 2x TC with less than seven elements will be crap.
On shift lenses, a TC will also (for practical purposes) increase the amount of your shift. The Canon TS-
E lenses go from 11mm shift to 15.4mm (1.4x) or 22mm shift (2x). Looking at image #3, guess where
you can now place your ground level. The horizontal format can suddenly lose the bottom third of your
building, when the centerline moves to 10mm below the bottom of the frame with a 2x. The vertical
format can move the centerline to 4mm below too. (Just as lens specs are not exact, teleconverter specs
can be pretty loose. A nominally 2x converter may be 1.8x or 1.9x. Never seem to be better than
advertised, even for Leitz and Zeiss.)
Now, compare the Canon TS-E 45mm/2.8 vs. the TS-E 90mm/2.8. With a 2x TC, the 45mm/2.8 turns
into a 90mm/5.6... but with 22mm shift possible instead of 11mm. Which sounds like more fun?
Since TC's in effect take their picture from the center of the objective lens' image, they avoid problems
that tend to arise in the corners of the objective.
But Wait! That's not All!
Any Shot with Lines!
The example buildings can be replaced with trees. Show those forest canopies while avoiding the "acid
trip trees" look. Or any other shot where there are two parallel lines... and if that sounds like "most
shots" you get the picture. Back before rolls of film were invented, there was a time when all camera
lenses shifted, and truing perspective was considered as important as focus and selecting shutter speed
and aperture. (Back then, they also used a variety of terms for shift: rise was shift up, etc. Archaic people
still do so today 8-)
With the first professional-use "box" cameras (as opposed to bellows cameras), a generation of
http://www.photo.net/photo/canon/tilt-shift (4 of 9)7/3/2005 2:24:04 AM