Introduced in 1986, the Canon T90 was one of the last and most advanced manual focus cameras Canon made that used their FD system of lenses.  Within a year the T90 would be supplanted by the rise of Canon's autofocus EOS system.  With that being said, this makes the T90 arguably the pinnacle of Canon manual focus design.

Despite its appearance, in that it looks like an autofocus camera from the 1990s, the T90 is really a manual focus camera.  It uses the FD system of lenses that has been the staple of Canon 35mm SLRs since the F-1 in 1971.  The T90's design incorporates a number of notable high points.  Since most camera controls no longer required mechanical buttons or switches, and were now controlled via electronic buttons, the camera's interface was completely redesigned with ergonomics in mind.  The placement of controls on the T90 is incredibly intuitive and can still be seen in part on Canon DSLR cameras to this day.  If you use a Canon DSLR, then a T90 will feel very familiar to you.

While the T90 does not necessarily add many functional innovations, it does combine several functions found in other cameras in ways that no other Canon to this point had done.  For example, the T90's metering modes include center weighted, partial area (a 13% measuring) and spot metering (2.7% spot).  In addition, the T90 emulated the multi-spot mode of the Olympus OM-4 that allowed up to eight spots to be metered and then averaged.  Additionally, the T90 has the ability to measure and compare highlights and shadows.

The T90 also has several exposures modes starting with full manual and including aperture priority, shutter priority and a couple of different Program modes for full camera control of shutter and aperture.  The aperture and shutter priority modes also have a safety switch that can be turned on in the event that the camera cannot balance off the manually set parameter.

Honestly, this list could go on and on.  We'll link the Wikipedia entry on the Canon T90 in the footnotes section and we highly recommend that you check it out.  

There are not many negatives regarding the Canon T90 but we should point out a few.  First off, as mentioned, it is manual focus only.  We only reiterate this point because if you see or are holding this camera, it is really easy to think it must be an autofocus camera.  It is not.  Second, while the T90 has a reputation as being a tank and highly durable, time wears down even the strongest mountain.  T90 cameras have begun to show their age.  The shutter in particular is prone to age-related failure.  This camera, due to its complexity, has become nearly impossible to repair.  There is a distinct lack of experienced technicians out there with the necessary spare parts to overhaul or fix these cameras.  Owning a T90 feels a bit like living on borrowed time these days and if you have the opportunity, we recommend having a spare body on hand as backup.

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