[Marktax]

Just bought a 60-250. I find no increase in zoom -- angle of view is no more narrow -- from slightly about 200 to 250. Any similar experience?

[narual]

Just bought a 60-250. I find no increase in zoom -- angle of view is no more narrow -- from slightly about 200 to 250. Any similar experience?

Are you focusing on something close or far away? Should be about 7.7 at 200 and 6.1 degrees at 250. That's not really very much, but it should be noticeable. I seem to remember something about internal focus zoom lenses not zooming so much when focused closely. I'm sure someone will chime in if that's the problem.

---------- Post added 09-26-14 at 04:23 PM ----------

Here's an explanation from the web

IF works by twiddling many internal factors to allow focusing without the whole lens having to move in and out. Standard lens design equations tell us that even if you extend a 200 mm lens by an extra 8" (200 mm) to focus more closely that it only focuses as close as 32" (800 mm). Do you really want your 18 - 200 to poke out an extra 8" as you focus, and then only focus to three feet? Of course not. This would be in addition to the extension you get when zooming to 200 mm.

IF works by deliberately shortening the focal length as you focus closer. Shortening the focal length internally has the same effect as moving the lens out to focus. Focal length is 200 mm at infinity where you need it and shortens as you focus closer.

IF lens are supposed to appear to have shorter focal lengths when compared to traditional lenses at close distances. Don't drive yourself crazy comparing since every IF design is a little different.