LF zoom lens. Or am I nuts.

Didn't Schneider or Rodenstock make a zoom lens for a short time a few years ago? If I remember right it had a very small amount of zoom and was made for only one or two years as a special order.

What was the lens and why would you want a LF zoom? Or is my memory going. Now what were we talking about?

Once upon a time, I had a Rietzschel Telinear lens, which I sold to a collector. As I recall, it seemed to have 4 elements, with variable separation between the front and back groups, giving effective focal lengths (I think) between about 200 and 600 mm (it was NOT strictly speaking a zoom, since it didn't stay in focus as you changed focal lengths). Have never seen another one, so I presume the idea didn't catch on, and I've never seen a zoom or vari-focal lens from Schneider or Rodenstock!

Regards,

David

It seems to me that such a thing would be really, really impractical. To really be a zoom at all (apart from the focus requirement - as David pointed out) it would be expected that the effective focal distance would stay constant. For THIS to be the case, the lens would, logically and by definition, be a retrofocus design. These usually require many elements to get the job done through a reasonable range of magnification. As such, a lens like this would necessarily be REALLY REALLY big(!!) and therefore probably very, very expensive.

There have been sveral variable-focal-length lenses, including many of the early telephoto lenses. But "true zooms" would be uselessly big, heavy and expensive, without coming close to the image quality of a simple meniscus lens.

Yes I do remember that there were large format zoom lens . . . .

However they were enlarger lenses, easier to make and modest apertures.

Ian