Hey guys, all of the info above has been very helpful.
I am picking up my new E-PL2 Oly housing PT-EP03 rig tomorrow and I was wondering what the wide angle options are for the stock port. They state on line that the current port fits the M.ZUIKO DIGITAL ED 9-18mm 1:4.0-5.6.
Has anyone tried this set up before or know of anyone that has? I am looking to avoid the extra cost of adding another port so it would be good to know how others have used this set up.
Thanks,
Lee
Remember that Olympus does not make the
Panasonic 7-14mm or 8mm fisheye lens, so they can't be expected to be extremely helpful about it. They only tell you
their 14-42 and 9-18 will fit their standard port, which is fact, they do fit and they do work. But the 9-18 will work a lot better in a dome port. Olympus does not sell a dome port for M43 lenses, so they don't tell you the many advantages of a dome. But you should know that a properly designed dome will give you both a wider field of view and sharper edges, and a dome becomes more necessary as you go to wider angles.
That is why Zen, Athena and 10bar make dome ports for the M43 lenses -- and they sell well because the domes really help widen the field and sharpen edges. One critical thing about the design of a dome is to place the nodal point of the lens coincident with the nodal point of the dome, if possible. Doing so keeps the focus the same in center as at edges, for a sharper image overall. That means the the optimal dome for a given lens may have a different length than one for a different lens with a different nodal point. For this reason Zen offers two different dome ports for the 9-18 and 7-14 lenses -- those two lenses have very different nodal points so need different length domes. So you might be able to physically use the 7-14 lens with a 9-18 dome, but might not work ideally. You probably need unique dome ports for optimal performance with ultra wide lenses. The 14-42 and 9-18 seem to work well sharing the 9-18mm Zen dome however, so Zen recommends the same dome for both, and that makes it a bargain among dome ports.
The Panasonic 8mm is a special case. This tiny lens needing a very short port body but a true hemispherical dome --- because it's field of view diagonally is 180 degrees and all points on the surface of the dome should be equidistant from the lens nodal point. To keep costs down, the dome is made small, with say a 2.5 inch radius. Still, an optical grade dome port for the 8mm lens from Zen or 10bar is expensive, about $800, which is 60% more than others cost.
Some say the 7-14 could benefit from a more hemispherical dome at 7mm too. If you read the post by Wisnu preceding, he comments that he might need the hemi dome instead of what he was using, to sharpen focus at edges at 7mm. Stopping down will help some.
