But! ^^ My God, what are these for .... Just take it with 35mm wide, it fits. Or in high format, take 10 pictures that overlap 20% and add it up (Panorama Free google), then you have a landscape with depth of field. 

You can of course choose shorter exposure times because of the open aperture, which may be an advantage in the shade, in the evening or in dark corners, especially if you are taking photos without a tripod. Where desired, the bokeh is also a dream. The depth of field can really play off best in strong foreground-background contrasts, such as in portraits. It's possible that the crop factor, e.g. with small format cameras like my 550 D, ensures that you get a slight telephoto effect, i.e. you might not get a complete sky on it at all. 

But! ^^ My God, what are these for .... Just take it with 35mm wide, it fits. Or in high format, take 10 pictures that overlap 20% and add it up (Panorama Free google), then you have a landscape with depth of field. 

Unfortunately this is for adapting lenses to Olympus' modern digital Micro 4/3 cameras. It won't work with the Pen FT or similar half-frame film cameras, and you most likely won't find anyone making adapters for these. 

1. You could consult us or search the mount information online
2. You could find the mount information on your instruction book when purchase the lens/camera
3. The mount information may be showed on front of the lens, side of the lens, rear of the lens or on the lens cap, usually it is a 2 or 3 letter code such as: CN, FD, OM, MAF, NK, N/AIS or F/AX