Powered zooms?

[Marcus Rowland]

In the last couple of weeks I've had a play with surprisingly similar 28-80mm powered AF zooms made by Pentax and Minolta for 35mm SLRs in the nineties, and seen a similarly-specified though different in appearance Canon zoom - couldn't try it because the seller didn't have a battery in the camera and wanted way too much money for me to buy it.

While I suppose powered zooms make some sense in video cameras, where you might want smooth zooming, and in bridge cameras etc. where the energy needed is relatively small, they don't seem to be very sensible in an SLR. I'd guess they were at least 10-20% heavier than non-powered equivalents, mechanically complex, and must have drawn a lot of power from the camera. It's notable that Pentax digital bodies won't power the zoom in these lenses, though AF etc. still work. It's also notable that the most common fault in the Pentax version is one of the switches falling off!

So... did Nikon ever play with this concept, and how bad were the results?

[Bjørn Rørslett]

Only for the mirrorless CX format to the best of my knowledge and this with an aim to provide a feature useful for video.

[Marcus Rowland]

Yes, it makes sense in mirrorless cameras which have smaller lenses etc. I just don't understand how anyone ever thought it was a good idea for 35mm SLRs at a time when batteries cost a couple of pounds!

[Akira]

Hi, Marcus, welcome to NG.

The auto-zoom might have been conceived for the surveillance purpose.  So long as the zoom optics is parfocal, you can change the angle-of-view from a remote place.

Or, the designer might be so lazy that he want to use the zooming-while-exposure technique automatically to get the radiating effect.