Small & Ultrawide Prime

wjiang

Mu-43 Legend
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Sep 7, 2013
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Christchurch, New Zealand
A stereoscopic reprojection would be better for faces in corners. I tend to prefer to reproject to something like Panini for such a wide FoV.

Fisheye are just as serious as rectilinear - I've never really used mine as a toy. You can't really replace one with the other. I'll never use a fisheye for architecture when I have a rectilinear UWA.
 

Naptown Gaijin

Mu-43 Rookie
Joined
May 4, 2018
Messages
10
People complain about the "distortion" of fisheye lenses, when a rectilinear is equally "distorted," of a different sort.

Rectilinear preserves angles, at the expense of areas. Fisheyes preserve areas, at the expense of angles.

Some notable uses for fisheyes include surveying objects, since you can count one square area of the image, and multiply to get an accurate overall count. Also, fisheyes are notable for not distorting people's faces that are in the edges and corners — something rectilinear fans often forget!

Check out the faces in the corner. You could not get away with this with a rectilinear lens!
View attachment 733389
The face in the lower right corner is grossly distorted...
 
Joined
Dec 31, 2012
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1,161
Could always just pick up the Rokinon or Samyang 7.5mm since both have a lens correction profile in lightroom..

The Laowa 7.5 would be the better choice, just having a hard time with that $500 price tag...

Thanks everyone for posting....

FYI, Rakuten.com/shop frequently has a 15% off coupon (max $60). Authorized camera dealers like Adorama sell on Rakuten so you can get the Laowa for $440 from an authorized dealer.

If you can go up to 9mm, the Oly 9-18mm is a great lens. You can find it used for $400. The PL 8-188 f2.8-4 is another option, though it is a bit pricier than the Oly 9-18. If you pay a little more, you can get a much more versatile lens.
 

wjiang

Mu-43 Legend
Joined
Sep 7, 2013
Messages
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Location
Christchurch, New Zealand
The face in the lower right corner is grossly distorted...
That particular shot is with a circular fish-eye giving a full 180 degree FoV (not just diagonal FoV), so it's the most extreme example possible. A more typically 180 diagonal FoV fish-eye is a lot tamer. A rectilinear lens trying to approach such a FoV would look ever more stretched at the edges as the FoV approached 180 degrees.

The point is that you can get away with those sorts of shots with a fish-eye. Try re-projecting a fish-eye shot to rectilinear and you'll usually get a completely unusable image.
 
Joined
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Salt Spring Island, British Columbia, Canada
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Jan Steinman
The face in the lower right corner is grossly distorted...
That is probably more due to being 86 years old than due to the fisheye lens. :)

Well, anything other than a focal length equal to the hypotenuse of the sensor (50mm for Fool Frame, 25mm for µ4/3rds) is going to give you a "distorted" image in some manner.

The faces in the corners have areas preserved, at the expense of angles. If you convert that image to rectilinear, angles will be preserved at the expense of areas. I think you'd perceive the rectilinear projection to be even more "distorted" than the ones in this image!

With either projection, the disconnection with what we call "reality" is not bad in the centre, but gets progressively worse toward the edges. If you run your prominent horizontal (like a horizon) through the centre of a fisheye scene, and also your prominent vertical (like a building corner), you can hardly notice the difference, until you move further towards the edges.

Either type of projection "distorts." If you understand what it does, you can choose the sort of distortion that is appropriate for your subject material. Landscape photographers generally prefer rectilinear. Scientific photography generally prefers fisheye.
 

Paul C

Mu-43 Regular
Joined
Oct 29, 2017
Messages
95
"Try re-projecting a fish-eye shot to rectilinear and you'll usually get a completely unusable image"

My advice is Yes - try it......and with the availability of excellent and free de-fishing software and a level horizon for shooting my experience is that "you'll usually get a completely usable image".

There are plenty of great photos posted online (and on the forum) taken with the popular 8mm F3.8 c-mount lens that has been available for several years now: with prices in the $50-65 range

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But the arrival of native M4/3 F2.8s at the current prices of $110-125 new raises the game for affordable M4/3 fisheye photography.

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Yes I'd love the 9-18mm Olympus zoom, and yes, shooting 3-4 overlapping panorama photos with the kit zoom at 14mm in the vertical format works great - but the first is still expensive and the second can't be done successfully when there is a lot of movement in the picture or significant forground objects in the composition.

Best of luck if you try this out - and don't forget to post the results for us to admire !
 

wjiang

Mu-43 Legend
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Sep 7, 2013
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Christchurch, New Zealand
I do a lot of re-projecting fish-eye, and full rectilinear reprojection usually looks horrible. There are better options.

Original
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Rectilinear. The people at the sides look very stretched. Note that you'll have to decide to crop it somewhere if you don't want something at such a wide aspect ratio, but then you lose a lot of the image.
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Custom Panini General - still have pretty much the whole width of the original, but at a more manageable aspect ratio, plus the people don't look too stretched.
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Dave in Wales

Mu-43 All-Pro
Joined
Nov 5, 2011
Messages
1,086
Location
West Wales
De-fish programmes which I have used for years.....
Fisheye Hemi, not free, I have the cheaper one and it's very easy to use.
Hugin, free, has a learning curve, but with the help of Youtube it's well worth persevering with.

The examples above are from Hugin I believe.

I use a Samyang/Rokinon 7.5mm FE, excellent IMVHO.
 

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