Which Zoom fisheye lens for MFT?

[WS007]

With the use of adapters, such as Metabones speed booster 0,71x or smart adapter 1x, FF or APS-C lenses can be used on MFT cameras. Nauticam supports housing of these adapters.

I plan to use a Canon mount fisheye zoom lens with Oly EM5MII UW (native MFT FE zoom lenses do not exist) and wonder wich combination may be better:

#1.: Canon 8-15mm FE (FF) with x1 adapter. Diagonal angle of view (AOV) would be 175-80 degrees.
Optimum AOV, but lot of light is lost as only fraction of image circle used for sensor image.

#2.: Tokina 10-17mm FE (APS-C) with x0,71 booster. AOV: (200, so cut off circle)180-105 degrees.
gain of aperture, because booster, but vignetting may be strong as more of the image circle of the lens is projected to sensor (crop 1,42x) compared to APS-C sensor w/o booster (crop 1,53x-1,62x depending on model).


Grateful for comments. Maybe someone tested out such combinations already...

Wolfgang

 

[bvanant]

I am not sure you will be happy with either. Focus is a real PITA with the metabones and the tokina. You will also lose the advantage of the circular fisheye since the 2x crop will cause some issues. Why not just get one of the 8 m fisheyes from Panasonic or Olympus?
Bill

 

[WS007]

Hi Bill,
I have the Zuiko 8mm FE and it is very good. The advantage of Zoom FE is that one can zoom out, when the objects do not allow the close approach required with the 8mm FE.
The Canon 8-15mm will not be circular at 2x crop, but instead approx. 175o-85o, depending on zoom (it starts at 8mm, so should be similar to the Zuiko 8mm FE). The Tokina with x0,71 booster (crop is 1,42x then) will cover approx. 180o-100o, simlilar to APS-C cameras (with pure x1 adapter it will be a partial circular fisheye at shorter focal length (=not attractive)).
For circular FE on MFT one would need the Sigma 4,5mm with adapter (0,71x in any case, but maybe the 1x is already enough to project the full circle on the sensor...).

One of the few shortcomings of the MFT format is, to my opinion, the lack of a native FE zoom lens and also circular FE. Therefore the urge for adapter...

Wolfgang

 

[Chris Ross]

A lot of light might be lost but the illumination on the sensor in light/unit if the same so there is no issue as you are just cropping to the centre of field. As for vignetting the m43 sensor is smaller than APS-C and sits up front close to the lens flange so vignetting seems unlikely to be a problem. They may well work but adapted lens never seem to work as well as you would hope.

I would think that one of the zoom through wet wide lenses would be a better option or even try the panasonic fisheye converter with the 14-42 lens, it fits the same dome as the Pany fisheye and only requires an extension ring to be added to you current dome. Nauticam make a zoom gear for it. A brief test is here: Panasonic Lumix G X Vario 14-42mm with Fisheye Converter DMW-GFC1 It doesn't seem like it quite gets 180° but it is pretty close