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Full Version: New Lenses from Olympus Coming
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frank

http://www.43rumors.com/ft5-first-images...us-lenses/

 

I am particularly interested in the 9mm fisheye cap but a slightly larger aperture would be better. Not sure how strongly the diffraction will affects the IQ.

Guest

Amazing how many 12-14 to 42-45mm zooms there are now. I'd be interested in one of the pancake ones, if the IQ is high.

Sylvain

Well,

 

Given how poor the other body cap was, I wouldn't give it a look. Eventhough it's a fun idea, I'd end up super quickly annoyed by its smeared images :-)

 

For the others, I'm curious about the 25mm, and I am disappointed to see YET another 14-42. I was happy with Panasonic 12mm wide idea.

 

I can't explain why, but I have a rather bad feeling about the E-M10 (if the rumours are true) and what these new lenses represent. Feels like that old time unsorted Olympus.

frank

Don't know if it's a roundish fisheye or a square fisheye. Will be cool if it's a roundish fish.

Yeah, that 9mm lens cap is quite cool. While I really like fisheyes I'm not that positive to carry one for seldom usage. That could be an option.

 

The 14-42 ... well, it has no IS and you know what I think about it ;-)

One possible advantage of the fisheye being f/8 is that you don't have to worry about focusing at all! It has been a long time since I used my E-P1 but from memory diffraction can be detectable at f/8, but unless pixel peeping the overall image was more than good enough.

 

From the focal length I'd imagine it'll cover the whole frame. Could it even give a 180 degree diagonal?

The diffraction on image level (and I guess that is what matters) is in the f16 on FF ballpark. With some smart sharpening one can get very usable results. Just not a lens for pixel peepers...

 

Do 16mm FF fisheyes give 180 degree view angles? I guess they do.

frank

Just checked: 18mm, F16, focused at 20cm (the minimum focus distance), then DoF = 12cm. Then the fisheye can even produce a blur background in some situation. (I have assumed that the DoF formula can be applied to a fisheye lens.)

On 180 degree diagonals, Canon and Sigma both seem to think 15mm is needed on FF. It gets more complicated in APS-C land. For example, we have the Samyang 8mm, and I see there's also a Sigma 10mm diagonal fisheye. Perhaps there's something in the way effective focal lengths are calculated (particularly with distortion) which means it is less clear cut. A nominal 9mm isn't too far out of the ball park. Based on the other cap lens, it is likely to be cheap and not the highest quality.

 

If anyone wants to bother, what would be a ball park hyperfocal distance for such a lens?

frank

Quote:If anyone wants to bother, what would be a ball park hyperfocal distance for such a lens?
 

69cm, according to the DoF formula.
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