Ultra wide angle: fisheye or rectilinear?

Without going too much in to detail about the whys, I can see myself having a need for an ultra wide angle lens in the near future. Essentially for wide interior shots, also some exterior. I've never much been a fan of wide angles, much less ultra wides and with the move to APS C digital, this is one area where my lens collection is severely lacking.

 

Once upon a time, this would have been an easy decision, if you wanted the fisheye look, you got a fisheye, otherwise you didn't.

 

In these days of easy digital manipulation, I'm thinking maybe it's not so clear cut anymore?

 

Does the ability to "defish" a fisheye make it a more versatile choice?

 

I'm looking at the Samyang 8mm fisheye or the 12mm rectilinear, in Fuji X mount if that makes any difference. They're both around the same price, so the decision really comes down to which is more versatile.

 

Thoughts?

 

If it makes a difference, my next lens up, in terms of focal length, will be a 35mm equivalent. I don't currently see a need for wider, except when it really has to be wide, hence the UWA.

If you defish an image the quality would be degraded but of course it may be OK for you. In which case you get much wider angle with the fish eye.

I'm a rectilinear guy who has owned but never kept a fisheye.

 

Even though "defishing" algorithms exist now, my biggest obstacle is being able to "see" what the final result will be after de-fishing. I'd rather deal with the weight/bulk/cost of a rectilinear and get a more-or-less what you see is what you get approach.

 

That's just me, though. I routinely shoot down to 14mm on full frame.

As far as I know, you can't defish at 180 degrees or more.

If you shoot with the fisheye you will have to correct the image AND likely have to crop the resulting image. I think . . . In any case, as noted above, you will not see, on the camera back, what you will get as your final image. If your final need is corrected images, I would go with the rectilinear lens hands down. But, for all that you wrote, you haven't told us the WHY, what it is that you are planning, so it's a little tough to give solid advice.

On rare occasions there is a perfect opportunity for Fisheye - I have seen a few dozen images at most in a lot of decades as a photography enthusiast. Rectilinear is a more useful lens across a broader scale of situations. Given the in camera and post processing capabilities available, I can't see much advantage to going the Fisheye route. The other factor at play can be an interest in experimenting with a particular lens - a while back I bought a PC Nikkor for that very reason.

For architectural interiors there's no argument. Rectilinear is the only way to go, and you'll still likely need to correct some substantial distortion at the widest settings. Technique will make all the difference, as one must keep a UWA plumb and level in order to avoid converging/diverging verticals. This is why a PC lens is so useful for architectural subjects, but that's a different discussion. In APS-C format, 12mm or wider is needful for interiors, or 16mm (or wider) in full frame. For other than architectural subjects, particularly interiors, there's less of a case for rectilinear over fisheye, but my preference still runs to rectilinear. You can use fisheye for interiors, but it becomes a creative treatment, and will not serve more documentary/communicative purposes.

The why is interior shots for clients, showing a wide sweep of an office, factory, castle, etc. It's not the main thing I'm proposing (corporate head shots and reportage), but it's something I can see clients asking for. I'd discounted panning and stitching as there may be people and movement.

 

Thanks, I hadn't thought about the difficulty in visualising the finished image, so it looks like rectilinear is the way to go then. Ideally I'd like to have a play with both, but that's not much of an option here.

When you defish, apart from the worsening of image quality, you also lose quite a bit through cropping. A better approach I think, is to take multiple shots from the same spot by rotating the camera at different angles both horizontal and vertical (a tripod with a ball head works best), then combining the frames in Photoshop. That way, you get better (undistorted, without soft edges or chromatic aberrations that fisheye lenses suffer from) image quality and also better coverage than a single ultra wide angle lens.

When you defish, apart from the worsening of image quality, you also lose quite a bit through cropping. A better approach I think, is to take multiple shots from the same spot by rotating the camera at different angles both horizontal and vertical (a tripod with a ball head works best), then combining the frames in Photoshop. That way, you get better (undistorted, without soft edges or chromatic aberrations that fisheye lenses suffer from) image quality and also better coverage than a single ultra wide angle lens.

Personally I prefer stitching with Microsoft ICE, which generally does a seamless job with no fuss (and it's free - unusual for Micro$oft)It's even coped with handheld shots taken from a moving boat :cool:

Re de-fishing: the effect of the deterioration is also dependent upon the size and display of the final image. As already mentioned, you'll lose (a substantial amount of?) image from the crop.

 

Here is an example to show what you lose . . .

 

15mm Fisheye Lnes 135 Format Camera

 

*

 

Defished

 

***

 

If I were shooting interiors with APS-C Format I would choose wider than a 12mm Rectilinear for my UWA Lens.

 

WW

Edited September 12, 2019 by William Michael

Personally I prefer stitching with Microsoft ICE, which generally does a seamless job with no fuss (and it's free - unusual for Micro$oft)It's even coped with handheld shots taken from a moving boat :cool:

 

I don't have experience with the Microsoft app, since I am on the Mac platform. So, my only option right now is Photoshop. I suppose, Microsoft will implement it's technology on mobile devices to automatically stitch the images taken in succession, like an extended panorama mode.

For extremely wide shots, you can take several shots with a rectilinear lens, overlapping about 25%, and stitch them together. The rendering can be rectilinear if the horizontal angle is less than 180 degrees, keeping all straight lines correct. For interiors, For more than 180 degrees, the rendering must be cylindrical, where vertical lines remain straight and vertical, but horizontal lines curve downward from the center. it's important to keep the camera absolutely level, and use (nodal) rail which allows you to pivot around the front node of the lens.

 

You lose about 10% of the image height by cropping, more if the camera is not level.

 

I use PTGUI for stitched panoramas. It has all the features you need to produce high quality, rectilinear interiors. It will also render multi-row shots, if you need added height, but getting the geometry right in a small space takes a dual-axis nodal fixture. The process can be automated with a DJI Ronin motorized gimbal.

Edited September 12, 2019 by Ed_Ingold

Just for reference, here's a couple of field documentary images I made last Friday using my Nikon D810 + Nikkor 16-35mm/4, at 16mm. I was documenting existing conditions in an old public works facility as part of a master plan I'm preparing. All of the images were hand-held, so some have a bit more converging line issues than if I had done a careful tripod setup for every shot. I've found 16mm (11-12mm on APS-C) to be sufficient for just about every interior situation, supplemented by careful stitching in really tight conditions (as in the second image). I use PS5 to stitch. I've never found a desire for a fisheye lens in the work I do, though I know there are others for whom they are a critical creative tool.

 

And here's a basic stitch of a tighter space:

(Oops! I forgot to flatten the layers before saving, so you can see, faintly, the stitch seams.)

Edited September 12, 2019 by DavidTriplett

This is an extreme example of a stitched panorama rendered as a rectilinear image. Notice that the rows of seats are straight, as are all other architectural features intended to be straight. There is a great deal of perspective (convergence), as one would expect with a wide angle lens. The balconies are supposed to be curved. The panorama consists of 5 frames, captured with a Nikon D2x (APS-C) and a 17 mm lens. With PTGui, no stitch lines are visible in the finished product.

 

The individual frames are rendered as cylindrical projections, in order to eliminate any steps at the boundaries. Once stitched, the image is stretched at the ends in a bow-tie fashion to render it as a rectilinear projection. Since I used a leveled tripod, nothing was cropped from the image height. Stretching and croping at the ends reduces the resolution to some extent. In practice, I generally crop panoramas to a 3:1 ratio. I left this one at about 5:1 for demonstration purposes.

 

Concert Hall, Seoul, Korea

Thanks, all, some really good advice.

 

I'll be going with the rectilinear lens for now, though I'll maybe pick up a fisheye for my own amusement at a later date.

 

Looks like the one thing I really am going to have to do though, is practice, as this is way, way out of my 35-50-85 comfort zone. So I'll get the lens and play with it until I understand it a bit better.

 

Thanks.

IMO, a rectilinear lens is the right solution. If you want something super-wide (< 21 mm), Samyang makes several which won't break the bank. The image quality is not that great, but you have to spend 3x as much for something better.

 

With one frame or many, you must level the camera for interiors. You can tilt it up or down as long as the camera remains level from side-to-side. Tilting the camera will cause vertical lines to converge, but since the center remains level, it is easy to correct the convergence in Photoshop (or Lightroom). When you correct convergence, you will lose a significant at the sides due to cropping. You will also shorten the apparent height of objects unless you adjust the top and bottom symmetrically (squeeze one, stretch the other), which closely emulates use of a rising front view camera.

Thanks Ed, it's the Samyang 12mm f2 that I'm looking at. The 10mm isn't much dearer, but it's twice the weight. Regardless, either is cheap enough that I should be able to sneak it past the matrimonial purchase review program. Manual focus doesn't bother me in the slightest, actually I prefer it, not that you really focus a lens this wide anyway.

 

The Fuji's have an electronic level, so I'm hoping that will be sufficient, as said, now I need to get my hands on one and play with it.

 

I use darktable and it has a variety of tools that should be useful, lens correction, keystone correction etcetera.

It's not enough to level the camera. The axis of rotation when you pan must be vertical, which means you must level the tripod legs, or have a leveling device between the tripod and the base of the head. If key objects are close enough (e.g., 75' or less), parallax will result in "ghosts" when stitching. To prevent this, the axis of roration and the front node of the lens must intersect. That's easy to set. With a nodal slide, turn the camera back and forth sideways, and move it along the slide until near objects don't move against the background.

 

The concert hall photo represents a significant challeng getting the images to overlap without loops and visible junctions. In the twelve years since it was taken, this was the first time I did a credible job creating the panorama. PTGui is not free, but it is the only program I can recommend for architecture, especially interiors. It works equally well for scenery, where there usually aren't any straight lines to manage. Even the seams are adjusted and irregular, so that moving objects don't make double images (ghosts). If you leave enough room, top and bottom, for cropping, you don't need a tripod for scenery.

In my experience, the main difference between the two lenses is that you will grow bored with the rectilinear lens in about two weeks and the fisheye in about two days.

Sanford has a point.

However a rectilinear lens can be more useful longer, maybe even a little longer than Sanford says.

 

The fish-eye lens is basically a one-trick pony.Most people can satisfy their yearning for this one with one of the auxiliary lenses. Some are terrible, but a few are good enough for "fun". (see Spiratone 180º Fish Eye (auxiliary) Lens)

 

In any case, I personally feel the results from doing it in the camera are still vastly superior to fussing around with angles and such in Photoshop or DxO etc.

 

If you are serious about interior and exterior architectural shots you need a tilt-and-shift lens or a view camera.

Edited September 13, 2019 by JDMvW

A super-wide lens may include too much ceiling and floor, making rooms seem much smaller than a stitched panorama. In my opinion, 20 mm is as wide as I care to use, when 24 mm doesn't do the job. In the example above, using a 17 mm lens on a DX camera is the equivalent of 25 mm. On the other hand, I would have used wider, since the ceiling is an integral part of the overall ambience of a concert hall.

A super-wide lens may include too much ceiling and floor, making rooms seem much smaller than a stitched panorama. In my opinion, 20 mm is as wide as I care to use, when 24 mm doesn't do the job. In the example above, using a 17 mm lens on a DX camera is the equivalent of 25 mm. On the other hand, I would have used wider, since the ceiling is an integral part of the overall ambience of a concert hall.

 

Isn't this an issue easily solved by cropping? This would allow showing the full width of the room, without too much of the floor or ceiling and void the need to be concern with stitching issues.

Crop, and lose all those precious pixels? Never! If I want more sky and dirt, I turn the camera on end.

 

Stitching is pretty easy, once you develop a routine, they're just not easy to print or display. Now that my portfolio is an iPad, I find stitched panoramas work pretty well. You can show the whole width, tap and enlarge, then drag to see the edges. Outdoors, I seldom use or need a tripod.

 

Mt. St. Helens, WA

Sony A7Riii + Batis 25/2 - Three stitched (horizontal) frames

Edited September 13, 2019 by Ed_Ingold

Stitching can work pretty well. I've taken panning shots on slide film and stitch the images together many years later.

 

You can also stitch verticals and even odd, non-linear, overlapping frames.

Edited September 14, 2019 by JDMvW