I got an email today from someone asking about portrait lenses.

Looking at her Flickr stream, she seemed to be using a Nikon D-80, which is a DSLR with a cropped sensor, so my answer leans a bit towards users of those cameras. For a long time, I used a Nikon D-100, which has a similar sensor.

Basically, the most important factor in a good portrait is not the lens or the camera that you use, but the level of connection and intimacy you can create between your subject and the viewer.

She asked for a recommendation for a prime lens, but in the end, it wasn’t my first suggestion. Shooting with primes is great, but it can be a lot of work. If you’re shooting a few hundred frames in a session, this can lead to a lot of pictures that look quite a lot alike. Getting something good in a short amount of time often requires a lot of different compositions.

In general, I despise most discussions about gear. No matter how much you try to speak in very general terms, someone will undoubtedly chime in to argue that the new Smegron 3-1500mm f:13.5 zoom that they heard will be announced at Photokina two years from now is the obvious best choice for portraits. These things are a matter of taste, which is really impossible to quantify. For example, one of my favorite portraits ever is one of the painter Francis Bacon, shot by John Deakin. I like it because it’s raw and unflattering, shot in close with a wide lens. In effect, he did it wrong and it works astoundingly well because of it.

Anyway, here’s what I wrote to her, perhaps some of you may find it useful as well:

Hi -

It depends a bit on the camera you use. If you are using a camera with a cropped sensor, like most of the digital SLRs on the market, you may find some of the more traditional portrait lenses to be a bit tight in composition. Still, if you like a close-cropped face in the portrait, something like an 85mm lens is still a good choice with a lot of flexibility. The 85 is a classic portrait lens for 35mm film photography. Being a slightly telephoto lens, it adds a bit of compression to the features of the subject, which is very often flattering. Wider lenses, especially those below 35mm, can be a bit unflattering, at the extreme making the subject appear moon-faced.

The kind of telephoto compression to which I refer is the effect you may have seen with a long telephoto lens, say a view down a crowded street from far away where the people appear almost stacked upon each other. When you read about lens equivalents with cropped sensors, they may say something to the effect of “a 50mm lens becomes an 80mm lens” but this is deceptive. A lens with a 50mm focal length will not have the telephoto compression of an 80mm lens, so you can’t expect the little bit of flattering that you’d get with an 80 or 85 millimeter lens.

That said, a 50mm lens is capable of taking excellent portraits, on any DSLR, regardless of sensor. You just need to get up and move your feet to do your composing. The same with an 85mm lens. It’s a lot of work to shoot a dynamic portrait session with a prime lens, but the benefits can be worth the effort. With any prime, you’re going to get good optics and a wider maximum aperture than on most zoom lenses. The wider the aperture, the more control you have over “bokeh” or out-of-focus blur, which can be good for isolating your subject from a distracting background. Wider apertures also let more light into the camera, allowing you to not only shoot in lower light, they help autofocus do it’s thing better and faster.

So for a good prime, I’d recommend getting the fastest 50mm prime you can justify getting. A 50mm f:1.8 can be had for between $80 and $120. That’s a simply fantastic price for a lens that fast. A bit faster f:1.4 will run you about $300. Canon makes a f:1.2, but it costs about $1,500. I have one of these and while it’s a real beauty, it’s a beast as well. It weighs a heck of a lot more than the others, which is a real consideration when shooting all day. I shot a model in my little studio the other day using that lens and others and after a couple of hours, my shoulders were simply aching. Still, the simply creamy blur it makes in out of focus areas makes it worth the pain—sometimes.

But you know what? If I had one lens to use for a portrait session where there’s be a lot of different poses and styles, where I need a lot of flexibility in composition, I honestly wouldn’t be shooting with a prime. For one thing, I often work in small spaces—my studio in Tokyo is about the size of a 1-car garage. Other times, shooting dancers, I’ll be on stage with them, with not a lot of space to move around.

In these cases, I use a zoom. On Canon, I like the 24-70 f:2.8 L zoom and on Nikon, I like the 28-70 f:2.8.

Both lenses are real workhorses. F:2.8 is about the fastest you can get in a zoom and they are pretty expensive and heavy, but I find them to be a good trade-off between price, weight and performance.

First, I’d take a good look at the lenses you own now. Even the “kit lenses” that come as an option for most DSLRs are often great, flexible lenses for portraits. After all, the makers know that a good percentage of new users will be soon taking their cameras to weddings or pointing them at newborn babies, so I suspect they optimize for those situations. In that case, you might best improve your portraits by getting a good flash with a diffuser or working on your composition. Get on your feet and engage your subject—your portraits will improve.

Shooting in your camera’s RAW mode makes a big difference as well. With that, you can go back and make subtle corrections to lighting and white balance, which is crucial for getting good skin tones.

Still, if you want a good prime, I’d try out a good 50mm. They’re just too much of a good value to pass up.

Good luck!

Jim