After purchasing my Panasonic GF1, I thought it’d be fun to exploit the small form-factor and smaller sensor and try some of the c-mount lenses that are out there on the micro 4/3rds camera. I purchased an adapter off of ebay that had both c-mount and M42 threads. I tried it with a TV lens that I bought off of ebay, and then an 8mm lens that I already had for my canon.
computar 8mm f/1.6:
I tried the 8mm computar first:
It’s a fixed-aperture lens that only cost about $5 or $10 from ebay. I didn’t have high hopes – just wanted something to play with.
Here’s a sample image taken with that lens:
The image circle isn’t very large, and it’s not very sharp. oh well. The lens could still be useful for video – the GF1 gives a 2x or 4x digital zoom option, and with 2x digital zoom there’s no vignette. the 2x digital zoom results in an 32mm 35mm-equivalent focal length though, which isn’t much wider than the standard 20mm f/1.7 kit lens.
peleng 8mm f/3.5 fisheye:
The Peleng is a little larger than the computar. I had to buy some cheapo M42 extension tubes to get the flange/sensor distance within a correct range. I used the wikipedia table to guesstimate how much more distance I needed, and the 9mm + 16mm extension tubes did the trick just fine.
It’s a bulky lens, and turning the aperture and focusing rings isn’t so easy on such a small-bodied camera. You have to grip the body really tightly in order to turn the damped focusing ring and the detented aperture ring. Luckily, at 8mm and f/3.5, everything’s basically in focus.
Photos with the fisheye are still fun in a fisheye sort of way:
and it’s still plenty-wide. The grill belongs to the Primo’s Parilla truck in Emeryville.
I think I took this photo near f/3.5, but I don’t remember. Sharpness is pretty much the same across the entire image, since the sensor is already only capturing part of the image circle. I’ll post 100% crops anyways:
There’s some standard sharpening and so on in lightroom.
here’s a corner crop:
and I’ll throw in a shot with the peleng on a 5D Mark I for crop-factor comparison:
conclusion:
The 8mm computar lens isn’t very useful at all, but it was fun to play with. The peleng on the GF1 is a pretty interesting combination with fisheye distortion, a wide field of view and sort of cumbersome handling. The image quality looks fine to me.