How many motors in Nikon AF bodies?

[subhasis_laha]

Please pardon my ignorance here: are there two separate motors in Nikon AF bodies - one for autofocusing and the other for film transport OR there is only one motor with approprite gears to perform both functions?

 

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I am particularly curious because the newly announced N80 body has a continuos film advance speed of 2.5fps while that figure for N70 is 3.7fps. If there is only one motor, then it could mean slower autofocus speed with the N80 (compared to N70) though the N80 does focus detection and lens movement in parallel (I do not think the N70 does that). Thanks in advance.

[bruce_rubenstein___nyc]

There almost has to be at least two in the body. Film transport and AF

make different demands on the motor and control system, and they also

have to work independently. The N80 is based on the N60 chassis which

accounts for the slower transport speed. Regardless of the design

details, I can't imagine introducing a camera with slower AF than the

model it was replacing. Nikon has probably determined that fast AF is

more important, to most people, than fast film transport.

[chuck]

Although N60 and N80 has similarly inadaquate meter coupling, the

differences in weight, dimension, and changes to internal arrangement

dictated by the big differnce in sizes AF condensor lenses and AF

modules suggests N80 is not built on the N60 chassis. It looks like

a entirely new chassis to me.

[paul staton]

The F4 and F5 have four motors in the bodies, film advance, film

rewind, focus, and shutter charging. I don't know the number in the

N-series bodies.