The Nikon N55 is similar to the N75 in many respects. However, there are a few features that are present on the N75 and not on the N55.
Some things the N55 Lacks compared to the N75:
TTL Flash
AF-S Autofocus
Aperture Preview
Two Focus zones (3 instead of 5)
Custom Features
Metal Lens Mount
Display Illumination
Exposure Lock Button
However, the N55 is still a vey capable camera, packed with other features like fast autofocus, Matrix metering, built-in flash and winder, shutter speeds from 30 sec to 1/2000 including "T," multiple exposure, bracketing, exposure compensation, A, P, S and M exposure modes, self timer, AF assist illumination, focus lock and more.
The AF-S lenses still work with all the metering modes, including Matrix.
The N55 can still be used with external flash, as long as the external flash has its own non-TTL sensor.
Here is an example of a configuration that works great and gives good results.
SB-28 in non-TTL Auto works great.
AF-S 24/1.4 lens gives focus confirmation with manual focus.
Also, a non-documented feature; the external 4-AA battery pack for the N75 works with the N55.
In general use, sometimes the lack of features is a plus. Operation is simpler. Perhaps less complexity can lead to improved freedom from failure in the long run.
Some things the N55 Lacks compared to the N75:
TTL Flash
AF-S Autofocus
Aperture Preview
Two Focus zones (3 instead of 5)
Custom Features
Metal Lens Mount
Display Illumination
Exposure Lock Button
However, the N55 is still a vey capable camera, packed with other features like fast autofocus, Matrix metering, built-in flash and winder, shutter speeds from 30 sec to 1/2000 including "T," multiple exposure, bracketing, exposure compensation, A, P, S and M exposure modes, self timer, AF assist illumination, focus lock and more.
The AF-S lenses still work with all the metering modes, including Matrix.
The N55 can still be used with external flash, as long as the external flash has its own non-TTL sensor.
Here is an example of a configuration that works great and gives good results.
SB-28 in non-TTL Auto works great.
AF-S 24/1.4 lens gives focus confirmation with manual focus.
Also, a non-documented feature; the external 4-AA battery pack for the N75 works with the N55.
In general use, sometimes the lack of features is a plus. Operation is simpler. Perhaps less complexity can lead to improved freedom from failure in the long run.