Oly 45 1.8 with Pana GTC1 converter... works !!!

Started May 17, 2012 | Discussions thread
Great Bustard Forum Pro • Posts: 40,681
Re: Rather different than how you put it.

kenw wrote:

Great Bustard wrote:

It makes the lens a 90 / 3.6, which is equivalent to a 180 / 7.2 on FF. Big, big difference between a 90 / 3.6 and a 180 / 1.8.

As already discussed in the thread it is a front mounted teleconverter so it is not a 90/3.6 (which would be the case for a rear mounted teleconverter). It would be a 90/1.8 for a properly sized front mount teleconverter.

Interesting. So a front end TC changes the diameter of the entrance pupil? Makes sense, I guess, since the entrance pupil (virtual aperture) is the diameter of the iris (physical aperture) as it appears through the front element, thus it makes sense that a front mount TC changes its size.

However, in this case it appears the front element may be undersized for a 90/1.8 so it probably isn't quite that either.

The FE would have to be 50mm to make the 45 / 1.8 into a 90 / 1.8. Even then, however, it would be equivalent to a 180 / 3.6 on FF. Still pretty good, though!

Post (hide subjects) Posted by
MT
MT
MT
MT
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow