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bobwysiwyg
5-Feb-2010, 07:31
I'm learning with a 4x5. I currently have three lenses, 135, 150, and 210. Recently, I found myself out with only one lens, because I wanted to try it, the 210. Unfortunately, it was way too narrow for a situation I found myself in and I could not back-up any further. Took the shot, though not what I wanted.

It did get me thinking though, since I'm not into any sort of distortion, for 4x5 what would be considered the widest without noticeable distortion in a final print?

Gem Singer
5-Feb-2010, 09:35
Probably a 90mm wide angle lens.

I say probably, because even a 90 will distort if not used properly. For example, close up portraiture.

bobwysiwyg
5-Feb-2010, 09:44
Thanks, that's kind of what I thought. It wouldn't be used for portraiture. I'll have to keep an eye out for something affordable.

Ed Richards
5-Feb-2010, 09:53
I use a 90 a lot, and while you can manage the distortion, you cannot manage the perspective effect - everything in the foreground is emphasized. If I was going to use one lens - and I did for a while when the rest of my kit was stolen - it would be a Nikon 120mm SW. It gives a normal perspective, but with a decent field of view, and it has unlimited movements on 4x5, so you can really adjust things like the foreground.

Kirk Gittings
5-Feb-2010, 10:03
I agree with Ed.

Mark Woods
5-Feb-2010, 10:36
Well stated Ed. That said, I use the 90 more than any other lens in my 4x5 kit.

Drew Wiley
5-Feb-2010, 11:50
Mark - there is a terminology problem here. Distortion is a function of lens design, not
focal length. On the other hand, the effect of diminishing perspective becomes exaggerated as focal lengths get shorter and shorter. Is this what you mean? It is
difficult to design wide angle lenses which are truly rectilinear and have a large image circle at the same time.

jb7
5-Feb-2010, 12:41
I agree with Drew.

Stretching around the edge of a large image circle is to do with projection, not distortion-
Although I don't know which particular lens you're referring to, of course-

Mark Woods
5-Feb-2010, 13:21
Hello Drew,

I think if you examine Ed's post he's describing the perspective issue -- which I really enjoy using. At the edge of the lens, there will be distortion and lens aberrations. The lens isn't designed to be used on the very edges and the design compromised can come into play. I don't enjoy those. I understand the difference between lens "distortions" (or lens defects, e.g., comma, chromatic aberrations, barrel distortion, pin cushion, etc.). None of that has anything to do with the perspective achieved with a wider lens that is sometimes mistaken by some people as "distortion." And I agree with your post on lens design and the difficulty with the wider lenses.

Drew Wiley
5-Feb-2010, 13:22
Comparing apples to apples, if I take a 120 lens with about 105 degrees of coverage,
like a Super Angulon or one of its clones, versus a wide-normal like my 125 W with
about 80 degree coverage, the Super-Angulon will show much more curvature of field
toward the margins of the print, creating that "stretched" look. But it will give me much
more coverage, especially rise, which is often vital in architecture. Yet both lens styles
appear free of barrel or pincusion distortion, so if your view camera back is aligned
parallel, your vertical will stay straight in either case. And because these two lenses
have almost the same perspective, being similar focal lengths, the convergence of lines
toward the horizon will recede at about the same rate. Eveness of illumination will differ, with the wider coverage lens often requiring a center grad filter. So it just depends on what you need the lens for. In architecture, I'd reach for the wide-normal
lens first if a lot of movement isn't needed - but often it is! A similarly constructed
90 mm lens won't necessarily distort any more, but will give a more rapidly diminishing
perspective. It's hard to make just one lens be the best for everything, especially when photographing interiors, where one simply can't always back up enough.

Drew Wiley
5-Feb-2010, 13:27
Sorry, Mark - I was apparently entering my above post just when you were. Personally
I gravitate toward the 120- look more than the 90, but often find the 90 necessary to
have on hand when architecture is involved. And frankly, unless space confinement is
the issue or there are depth of field problems, I prefer to avoid wide-angle lenses
altogether!

jb7
5-Feb-2010, 13:40
In my experience, the issue has more to do with how you populate the edge of image circle-
I have plenty of ultra wide pictures where you would be hard pressed to see any 'distortion'.

To me, it's just geometric projection-
if you choose to place an object on the edge of the circle, it's going to get stretched-
it's the same if you do a drawing.

You can choose to place nothing but space and light on the edge of the frame,
in which case, no attention is drawn to the lens.

It's not so much an inherent effect of a lens, it's how you choose to use it-

Bruce Watson
5-Feb-2010, 13:59
Mark - there is a terminology problem here. Distortion is a function of lens design, not focal length. On the other hand, the effect of diminishing perspective becomes exaggerated as focal lengths get shorter and shorter. Is this what you mean? It is difficult to design wide angle lenses which are truly rectilinear and have a large image circle at the same time.

Indeed. Distortion is a broad term. When you think about it, all photography is distortion -- the rendering of a 3D scene down to a 2D representation. How this is done can create more or less obvious discrepancies, but they are all distortions of reality.

In fact, this is the whole point of photography: to distort reality in a way that works for the purposes of the photographer. You'll find that some like certain effects to the point that much of their work involves their favorites. You'll find wide angle people, long lens people, people that like a normal perspective only, people that specialize in near-far shots, people who like to level and plumb their film planes to avoid keystoning, people who like rear tilt to make the foreground loom and don't care a wit about keystoning. And many more I'm sure.

Optical distortion, OTOH, has a specific definition, typically a deviation from rectilinear projection. And by that definition some very wide angle lenses for LF are in fact very low distortion. Typically more modern lens designs are better at this than older designs. I'm thinking I read somewhere a while back that the venerable 72mm super angulon was considered a very low distortion lens. But I've never used one, so what do I know?

I guess what I'm saying is that it's typically not the lens, but how you use the lens. You can almost always find a way to make the photograph you want with the equipment available to you, if you have the skill and the patience of course. ;) That's the joy of LF -- the huge amount of control the photographer has over the resultant image. This control is typically not intuitively obvious however; it's a hard won skill that is the result of months-years of work and practice. Well worth learning IMHO.

Drew Wiley
5-Feb-2010, 14:12
Joseph & Bruce - you are making some very relevant remarks. In fact, my whole attitude toward wide-angle and composition is completely different with an MF SLR than with a view camera, simply because the same correction parameters do not exist.
Whole different ball game.

bobwysiwyg
5-Feb-2010, 14:17
Didn't mean to start anything. :) My original reference to 'distortion' was when, for example horizontal and vertical lines are no longer either vertical or horizontal.

Drew Wiley
5-Feb-2010, 14:37
Bob - with most of the name-brand modern wide-angles you're going to be able to keep verticals and horizontals parallel if you correctly use the movements on your 4x5.
Virtually all of these lenses are now well engineered to prevent barrel or pincushion
distortion, at least within the recommended coverage of the paticular lens. But the overall "look" and angle of perspective will obviously differ with different focal lengths.

bobwysiwyg
5-Feb-2010, 14:40
Oh, I have to correctly use the camera movements? Still working on that one. :)

Kirk Gittings
5-Feb-2010, 14:51
Bob in trying to figure out exactly what you mean, there is distortion and then there is exaggerated perspective. If you look at my web sight you will see tons of work with a 90 that has no distortion but have very exaggerated perspective. For my color commercial work that adds a kind of dynamism to the image, but for my personal work I don't like it because it screams "shot with a wide angle lens" and IMO is a diversion to the message. So on the personal work I rarely exceed a 120. Make sense?

Bruce Watson
5-Feb-2010, 15:00
Didn't mean to start anything. :) My original reference to 'distortion' was when, for example horizontal and vertical lines are no longer either vertical or horizontal.

As in, parallel lines in the subject aren't parallel in the photograph? That's usually a problem with keeping the film plane parallel to the subject. This is why some people like to level and plumb the film plane. For example, in landscape work this is done to keep the trees parallel to each other instead of leaning in toward each other in the photograph.