push pull

[molestrangler]

Please forgive me if this is an obvious question, but this is all new to me, why are push pull lenses cheaper than twist type ?

[Simpo Two]

Possibly because they're older, or don't have AF? Not sure.

Years ago I had a 'one-touch' Vivitar Series One 70-210 f3.5 - great lens.

[horacethefrog]

Mmmm, not sure I'd call the Canon 28-300L or 35-350L cheap! They're very tricky to use and, considering the amount of negative comment they attract, Canon must have a very good technical reason for making them that way although I have no idea what it is. I've never heard a positive comment about that aspect of their design. I think the 100-400L is the same?

[RobDickinson]

Push/pull is a lot quicker to get fast zooming, people dont tend to like the 100-400L for it because 'it sucks in dust' IMO thats bks, the lens has to extend the same distance irrispective of the mechanics.

[bashful]

I don't know about 'cheaper', but I'm guessing the issue with something like my Canon 100-400 is that the front element has to move eight or ten inches. Bearing in mind your wrist can only comfortably handle a twist of 120-180 degrees, a twist-zoom mechanism would have to be pretty highly geared to move the element that far. That would make it harder work and less precise.

[Goldeeno]

I love the 100-400, the push pull doesn't bother me, you get used to it

[molestrangler]

The reason for the question was there was a chance for a Nikon 80-200 f2.8 push pull in mint condition for sensible money, and as I've only just started and have only a prime 50mm I thought it might be worth a go.

[Simpo Two]

As i understand it the Nikon 80-200 is a very good lens optically, but now overhsadowed by the 70-200 VR, so it's not as 'desirable' as it once was. There have been several versions of the 80-200; perhaps the one you're looking at is not AF-S but screw-drive AF, which is slower. Again this would reduce the desirability of the lens.

[EmmaP]

I thought that this was going to be a thread about push and pull processing. As you were...