Many photographers buy a wide-angle lens thinking its primary purpose is to take sweeping panoramas, to get the entire scene into the frame. It definitely does that, of course, and if you stand on the rim of the Grand Canyon with a 14mm lens, you will encompass most of this giant chasm.
However, I think the real power of a wide angle - as evidenced by the pictures in this article - is to distort reality. The word distortion has a pejorative connotation, so let me rephrase. I will say it this way: A wide-angle lens is most effective when it (1) exaggerates perspective, (2) makes the foreground disproportionately large compared to the background, and (3) makes the background seem much further away than it really is.
For instance, the photo above shows my wife in a pool in Budapest, Hungary, and I was about two feet away from her. That's why she seems unusually large in comparison to the background.
Another example is the picture below of the driftwood on a beach in South Carolina near Charleston. The wood seems huge compared to the background, and this occurred simply because I placed my 14mm lens very close to the wood. In this case, the camera was about 18 inches away from it.
Of course, our eyes never see images like this. So what? No one ever said a camera must capture what we see. Sometimes it does and sometimes it doesn't. We are dealing with a visual, artistic medium, and a wide-angle lens is a tool at our disposal to create some extremely unique images. The wider the angle, the more extreme will be the distortion.
The closer you place the lens to the foreground, the more distortion you'll see. The large leaf in front of the waterfall I shot in Costa Rica, above, was only about two feet away from my lens.
The flowers below that I found in the Swiss Alps didn't seem this large compared to the sky when I stood there looking at them, but a 16mm focal-length lens placed about three feet away from the foreground flowers created this type of look.
The formula, so to speak, for achieving this style is:
2. Place the camera very close to the foreground (between 2 and 5 feet),
3. Use a small lens aperture for complete depth of field,
4. Use a tripod.
I learned a lot about lenses from my years with photo magazines and contact with all camera and lens manufacturers. This affects how I look at lenses and a lot of it is not common knowledge. I also believe that the best lens is one you can afford and does the job you need it to do, not the lens that has the best "test pattern" scores (how often do we photograph test patterns?) or the one that Bill at the camera club thinks is the only good one. So I thought it would be interesting to talk a bit about lenses.
This started when I began working with Tamron and their new 18-270mm VC ultra zoom. With comments and questions I got, especially from one especially prickly venue, this reminded me to think about lenses in ways I had not done for a while. First, though, why I decided to work with Tamron and to use their lens for a while.
Canon, Nikon, Olympus and Sony are big sponsors of photographers. Yet most people don't know that when a sponsored photographer is talking about his Canon or Olympus camera gear, for example, that is the only gear he or she can use or talk about. I know these people, on both sides, and I think they are honest caring folks who really do like the gear they are shooting with. To think otherwise is, to be blunt, mean-spirited, cynical and naive - manufacturers don't pay that well and no pro will jeopardize their work with crappy gear.
Still, that creates a very unfair market for companies like Tamron, Sigma and Tokina. It gives the impression that a photographer is a "purist" and that somehow these "non-manufacturer" lenses are not as good. The fact that the photographer can only shoot with the manufacturer's gear is never mentioned. In addition, there are a lot of high-profile photographers who desperately want a relationship with a major manufacturer and so will never work with a lens like the Tamron, no matter how good it might be, because they think it might affect their chances of getting picked up by a major.
So when Tamron approached me for a short term relationship, I thought this was an opportunity to provide some balance, plus I know the Tamron folk and why not shoot what I want and explore what a lens really might be able to do? And Tamron did not require me to only use their gear, nor did they ask for a positive review, nor did they ask to keep this relationship quiet.
Can a Cheap Lens Match a Pro Lens?
Let's think about lenses. There seems to be a myth that lenses are "one thing", so you can hunt for that great bargain and buy an inexpensive lens that will match an expensive lens. Now in what product world would that true?! Sure, go buy a cheap Chevrolet and expect it to match a BMW!
Oh, wait. I can take a cheap kit lens that comes with a low-priced camera and beat any professional, expensive lens. How is that possible? I use a tripod and the person with the expensive lens does not. Or I pay attention to the craft of my shooting, carefully choosing f-stop and shutter speed for sharpness, watching how I hold the camera and squeeze the shutter, and the person with the expensive lens does not.
Think those are unusual conditions? Not at all. I see folks with expensive lenses and cheap tripods at places like Yosemite all the time - they wasted their money on the expensive lens. I see people handholding cameras badly all the time. I have done some tests with a variety of people and find that most photographers over-estimate their ability to sharply hold a camera, especially with moderate shutter speeds.
Manufacturers roughly divide cameras and lenses into three groups: entry-level, mid-range and pro. If you compare similar lenses within any group across manufacturers, you will find that today's lens technology is so readily available that the lenses are pretty similar in quality. While price is involved, you have to compare the same technology, design, focal length and maximum f-stop for price to be comparable, too.
Kit lenses from camera companies are very similar, as well as low-priced lenses similar to them from Tamron, Sigma and Tokina. But a kit lens is designed for that entry-level market, not for a pro market. So what can you usually expect from them and other very low-priced lenses? Decent image quality, but the lenses will definitely be distinctly less sharp wide-open and also stopped way down (such as f/22 and smaller). Also, you will often find significant barrel distortion at wide-angle settings (this is the curvature of straight lines near the edges of the frame - though frankly, this is not as big a concern for nature photography where straight lines are not common).
These lenses are not built for harsh use and are not sealed at all against rain and dust. They will also be typically more sensitive to lens flare. And they will be slow, meaning their maximum f-stop will not be very wide. You will also find that there is often vignetting when such lenses are shot wide-open with the widest f-stops.
Now I think it is unfair and unrealistic to think everyone is going to be able to afford something else if they have an entry-level lens. I know when I got started that buying lenses was difficult, and when our kids were young, impossible. So if you have such a lens and want maximum quality from your images, what do you do? Complain you don't have a more expensive lens? NO! Shoot at middle f-stops, such as f/8 and f/11, be very careful about handholding the camera and lens, and use a GOOD tripod whenever you can. Always use a lens shade and block bright lights from hitting the lens when you can. In other words, pay attention to the craft of your photography. And if the barrel distortion bothers you, correct it in Photoshop or Lightroom (which is very easy to do).
An aside - a GOOD tripod is a better investment than a high-priced lens and will more likely give you consistently better results.
This category is an important part of the photo market. The Tamron 18-270mm VC ultra zoom is in this category. These are quality lenses that are often designed for maximum versatility. There is a great deal of price pressure on this market (the profit margins are very low compared to pro lenses), so cost is often surprisingly low. The Tamron 18-270mm offers a very big zoom range in what is to me, an amazingly small and lightweight lens.
"But Rob, you have to say that because of Tamron." You don't have to be a rocket scientist to figure this out. Just look at the specs. First, the zoom range is remarkable - no lenses have anything close in its size of 3.8-inches long and weight of less than a pound. If you don't think all of that is amazing, then you have not been paying attention to the photo gear market.
For example, the Canon EF-S 18-200mm is a very comparable mid-level lens (which I have shot and find has similar qualities to the Tamron) that has less focal length range (though slightly wider max aperture) in a larger lens (6.4 inches and 20 ounces). Nikon's 18-200mm is also comparable, again with less focal length, and is a 3.8-inch, 20 ounce lens that focuses to 20 inches.
So what can you expect in a mid-level lens? Better image quality than entry level lenses, though you will still see a difference from wide-open/stopped way down with the mid-range f-stops.
These lenses often incorporate very modern optical designs that were extremely expensive to produce not all that long ago. There is usually less barrel distortion when the zoom range is not too extreme. However, all extreme zoom lenses I have tried typically have some of this edge distortion, though I was surprised to find how much this was reduced in the Tamron.
While mid-level lenses are better sealed against rain and dust than entry-level lenses, still, that is minimal and I would not recommend taking these out into the rain unprotected. Since the market for mid-level lenses wants smaller and lighter lenses, these lenses are designed with that in mind rather than dealing with rough use. I have no idea what that means for the Tamron. I tend to be very careful in how I handle my lenses and cameras. That is one reason why, I think, I can safely rely on my Canon 60D rather than taking out the "better made" 7D that I also own - I love the tilting LCD of the 60D. Gear that meets my needs is more important than some arbitrary "better" standard such as the 7D vs. the 60D.
Mid-level lenses will typically be less sensitive to flare, though all complex zoom lenses will have their challenges simply because of all of the glass involved inside the lens. I have found the new Tamron 18-270 to control flare very well. How fast the lens is depends on the focal length range of a zoom and its physical size. Optically, it is simply impossible to create a small, compact lens with a big zoom range and get a wide aperture. Physics does not allow it. So mid-level zooms with shorter zoom ranges will be faster (wider max f-stop) than mid-level zooms with big ranges. Sometimes you will find vignetting in these lenses, but this is often more of a function of the age of the lens design (older designs tended to be really susceptible to this) and how big the zoom range is. I have found some slight vignetting with the Tamron, for example, but only at extreme zoom positions with the widest f-stop.
So if you have a mid-range lens and want maximum quality from your images, what do you do? Complain you don't have a more expensive lens? NO! That comparison to a more expensive lens starts to break down with the mid-level lenses because you start to have features here that simply don't exist in the most expensive lenses.
A good example of this is size and zoom range. Small size and big range do really well in the mid-level market, so lens manufacturers make lenses that meet that need. Pros typically are less interested in small size and big range, plus they want faster lenses (wider max apertures), so lens manufacturers make few lenses with those specs for them. If you want the features of small size, big zoom range, you have to look in the mid-level lenses.
You need to again practice your craft as a photographer and do exactly the things I mentioned in the entry-level section about getting the most from a lens. This is not a secret formula - those elements of craft have been around for a very long time and you can find the same ideas in photo how-to books of 50 years ago. They are both timeless and that important. I will be a little harsh here - a lot of photographers are more interested in buying a "pro lens" than in putting in the effort to master their craft as a photographer. The "pro lens" must be good, so they are willing to spend the extra money rather than working on their craft, and then they think they have a great lens just because it cost a lot rather than working to get the best possible results from any lens (including that one).
Finally, there are the pro lenses. Pro lenses are made to the highest standards, there is no question about that. They have the best in image quality and will often have excellent image quality with all f-stops. That said, I don't want someone saying, "But such and such a pro lens is not that sharp." There are exceptions and there can be a "lemon" in such a product. Barrel distortion is highly corrected in pro lenses, though you will still sometimes see it with some extreme wide-angles.
Pro lenses are designed for harsh use and most are well sealed against rain and dust. You can take these out in a moderate rain and shoot with them without damage. And the lenses can be handled roughly and still keep working well. This level of lens is extremely well corrected to minimize lens flare. Does that mean you will never get lens flare? No! Optics are always susceptible to flare, these lenses just keep it to a minimum. Finally, vignetting is also minimal to non-existant with such lenses (though you will often still find it with very wide-angle focal lengths, which is why Lightroom has a control to get rid of this problem if you want to).
The Best Lens
So what's the best lens? The lens you can afford and can use. A lens on the camera used to capture the subjects and scenes you care about is always superior to the one that anyone else has but is not on your camera! I literally grew up loving photography and being able to afford nothing, so maybe that is why I love and appreciate every lens that is on my camera. I am more interested in how a lens helps me photograph than in camera-club arguments about which is "best." The best lens is the lens most appropriate to your needs, that you own and that you use.