12mm Heliar on Micro 4/3?

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I'd like to see any images taken with this combo, with particular attention to corner sharpness, as well as images of the camera with the lens on it. I have been contemplating the new Oly 9-18 zoom, but for the same price could get the LTM version of this lens, with finder, and use it both on m4/3 and on my Leicas. That is, if the images and handling are up to snuff on m4/3.

Anyone?
 
I tried one on my daughters gf1 and was disappointed by the corner softness, but to be fair I have no idea if I had it set-up correctly and I only had it briefly, she snatched it back when she realised I was playing with it (I’m not trusted with technology at home)
 
I tried one on my daughters gf1 and was disappointed by the corner softness, but to be fair I have no idea if I had it set-up correctly and I only had it briefly, she snatched it back when she realised I was playing with it (I’m not trusted with technology at home)

Ha!, you created a monster! ;)
 
yep ... starting to look that way ...



… not sure I can cope with the competition
 
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cv 12 on ep1

cv 12 on ep1

Here's a shot with the cv12 on my ep1... wide open and focused midrange. I don't think corner softness will be a problem since your just using the center of the lens.


4087865146_cac8c2835d_b.jpg
 
Here's a shot with the cv12 on my ep1... wide open and focused midrange. I don't think corner softness will be a problem since your just using the center of the lens.

Thanks! That looks pretty good. The m4/3 sensor is notoriously corner-smeary with Leica-mount wides--the sensor isn't designed for oblique light rays the way the M8 and M9 sensors are.
 
You need to realize the DoF scales are two stops off for m4/3. At f/11, use the f/5.6 scales.

I tried to get smeary for you. My dog is "smeary," but that is not the lens's fault. That was taken at f/5.6 at 0.7m (today). I have the tree photo where the camera is really close to the tree and stopped down. The second pic is of the top and bottom corners on the right side of the frame--there is some CA in the branches, but the softness could just as well be DoF.

Corners are soft, but I don't think they are "smeary." In a sense they are worse on a computer as you can pixel peep. I have made 16x20 prints from a 12mm image and it was very nice. I would compare this lens to the Olympus 17mm in terms of sharpness.

All with an E-P1. (All full frame. Except for the crops.)
 

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The m4/3 sensor is notoriously corner-smeary with Leica-mount wides--the sensor isn't designed for oblique light rays the way the M8 and M9 sensors are.

I wonder if folks have not give these lenses a bad rap in part because they do not use the DoF scales correctly.
 
'Sides, the lens looks good on the camera. And lookin' good is half the fun...
 

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What happens when you shoot a brick wall with a CV 12 or 15 on the u4/3 sensor?

Or what about infinity photos (> 1 km)?

Why does the DOF change? Isn't it the same lens, you just have a cropped image result, relative to FF 35mm film/sensor?
 
I didn't try cv12mm on my GH1 but I've tried zm 21mm f/4.5 and cv 15mm f/4.5 on both GH1 and Leica M8.
The corner sharpness of RF lens on GH1 is disappointing.
I tested them on a tripod with same focus distance setting.
Both lens show better corner sharpness on M8 (please note that M8 has a much larger sensor).
I think the problem is on the sensor of m43 camera, which is not desinged to handle oblique light.
My conclusion is to use native M43 wide angle lens if you want better corner sharpness.
 
Yes, I am well aware of that. But different lenses behave differently, and the 12mm is thought to behave better than the 15 on m4/3. And I have the 15 and the corners are ok to me.

As for the DOF scale, I don't concern myself too much with that, on a system where it is easy to see it directly on the screen or in the EVF.
 
What happens when you shoot a brick wall with a CV 12 or 15 on the u4/3 sensor?

Or what about infinity photos (> 1 km)?

Why does the DOF change? Isn't it the same lens, you just have a cropped image result, relative to FF 35mm film/sensor?

DoF is related to the circles of confusion. Since the m4/3 is half a 35mm frame, the image is effective enlarged 2x for the same display size. Those circles are too. So for a m4/3, the permissible circle of confusion (a spot that looks sharp) needs to be twice as small as one on a 35mm camera. So when using a 35mm lens with DoF scales on an m4/3 camera, you need to use the scales for two stop more open than what the aperture is set to.

I just wish the 12mm Heliar had f/4 and f/2.8 scales. But for some reason Cosina did not put them on their f/5.6 lens...
 
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