laptoprob
back to basics
This speed booster is optimized optically for APSC, but mounted with a m43 bayonet. With APSC, the original field of view is almost unchanged, with m43 there remains a 1,44 crop factor, instead of the 2 without the optics.
I just received the adapter and changed the EOS mount for an Alpha mount, because I have some manual focus Minolta glass adapted to the Alpha mount. Here is a quick first test.
Wow! The 58/1,2 (on the glassless adapter it's like 118/1,2) becomes a 84/0,83! The dof and bokeh aren't changed. First photo is the 58 on an 'empty' adapter, then on the Roxsen speedbooster. Last one is the Navitron 75/1,3. The first one is on minimum shutter speed wide open, the last two are a bit overexposed... You can also see the 75/1,3 fits the m4/3 sensor well, because the overexposure is somewhere between the '84/0,83' and the '118/1,2'. Without booster, clearly a lot of light is lost.
The booster does add some vignetting. By f4, that vignetting is almost gone. Sharpness doesn't really seem changed. The original 58/1,2 isn't a winner in the corners wide open anyway. By f4 the sharpness is good, center and corners.
I just received the adapter and changed the EOS mount for an Alpha mount, because I have some manual focus Minolta glass adapted to the Alpha mount. Here is a quick first test.
Wow! The 58/1,2 (on the glassless adapter it's like 118/1,2) becomes a 84/0,83! The dof and bokeh aren't changed. First photo is the 58 on an 'empty' adapter, then on the Roxsen speedbooster. Last one is the Navitron 75/1,3. The first one is on minimum shutter speed wide open, the last two are a bit overexposed... You can also see the 75/1,3 fits the m4/3 sensor well, because the overexposure is somewhere between the '84/0,83' and the '118/1,2'. Without booster, clearly a lot of light is lost.
The booster does add some vignetting. By f4, that vignetting is almost gone. Sharpness doesn't really seem changed. The original 58/1,2 isn't a winner in the corners wide open anyway. By f4 the sharpness is good, center and corners.
