What lens should I use for taking a portrait photograph of someone’s face? You will see this question asked time and time again by aspiring photographers. The reason it is asked is that they often don’t have long enough lenses and are disappointed when they use short focal length lenses. Or they can’t believe it is a good idea to step back and use a long focal length lens.
I took this photograph of a young Asian woman with a 105mm lens on a DX camera. That is equivalent to a lens with a focal length of 157.5mm in full frame. That is not a short focal length lens.
You can see more portraits here on the Portrait Gallery page.
My Recommendations
At the end of this article I’ve put some of my recommendations for Nikon portrait lenses.
Why Step Back
The reason it is a good idea to step back and use a long lens is because otherwise you get unflattering perspective distortion.
What Causes Perspective Distortion
Distortion is a function of how far the camera is from the subject – the closer to the subject, the more you will get the kind of distortion that doesn’t look flattering in a portrait.
Unflattering distortion is not a function of the focal length of the lens. It is only a matter of how far the camera is from the subject.
That is all there is to it.
What Perspective Distortion Looks Like
The effects of distortion are easy to see.
Let’s suppose you are photographing someone who is looking straight at the camera. If you stand close, the subject’s nose will look bigger than it really is. It will look a mile long and the eyes will look set closer together than they really are and will seem to disappear around the sides of the face.
If the photographer shoots from a greater distance however, the face flattens out, the nose looks smaller and the sides of the face almost seem to unwrap. Eyes look bigger, noses look smaller, and faces look more attractive.
Why You Should Use A Long Focal Length Lens
Of course, you could step back even with a short focal length lens. That’s true, but then the subject is only going to cover a small part of the frame.
You could then crop the photograph later. This will work but of course there is a limit to how far you can crop a photo before it starts to lose definition because there are not enough pixels to produce a good looking image.
It’s better to use a longer focal length lens and use all the pixels you camera has to offer.
Of course if you are taking a full body shot, then you can use a shorter lens, but even here you will get a more flattering shape with a longer lens. I have taken shots with a 50mm equivalent lens for full body shots or even head to waist shots but a longer lens is still preferable.
When You Do Not Need To Use A Long Focal Length Lens
Babies usually have fairly flat faces, tiny noses and big eyes, so they look good even when photographed from close up with a short lens. I have seen lovely portraits of babies taken even with a very short 28mm lens.
Cats photographed straight on look great with a shorter lens. I photographed this cat with a Nikon 60mm AF-S macro lens on a Nikon D60, so that was the equivalent of a 90mm lens full-frame.
The Effect Of A Normal Viewing Distance
Actually, the amount of perceived distortion of the resulting photograph is also a function of how far away the viewer stands from the photo.
Our perception of what looks correct and what look distorted is based on looking at things from what is called a normal viewing distance. Change that distance and our perceptions change.
Rather than take an unflattering photograph of a model, I took a photograph of a motor car. I think you will agree that this photo makes the car looks distorted.
Red Car Photographed With 18mm Lens
But bring your face within a couple of inches of the screen and I am pretty sure you will agree that there is less distortion. There is a larger version of this photograph here on this page entitled Perspective Distortion and it is easier to see there.
Leave a comment here to let me know whether this is your experience.
Lenses
I am only recommending lenses that I have used. I have read reviews of other lenses but I cannot endorse lenses that I have not used myself. The Nikon 105mm F2.0 DC lens is one of the sharpest lenses that Nikon ever made. It has the added advantage of incorporating a control to allow the background to be defocused even more than in its neutral state, which helps to separate the subject from the background.
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What about the NIKKOR 105mm 2.8? I know the aperture isn’t quite as wide, but it does have the added function of the macro. What are your thoughts?
James recently posted..Coffee for one
The extra one stop of light is worth it, for its light gathering ability but I don’t think it is that important for separating the subject from the background in most situations.
The nice thing about portraits is that you can usually set them up so that the background is neutral and far behind the subject.
However for environmental portraits where the background cannot be controlled, every bit of assistance is making the background less dominant is worth it, in my opinion. The depth of field of the 105mm at f2 is already quite shallow, but a bit more always helps.
You are right of course about the macro facility of the 105mm. I have the Nikon 60mm AF-S macro lens and that works well enough. I used it for some of the shots for the Details In Nature section at Quillcards, and I don’t need to think about macro in a longer lens. Having said that, if I had to make a choice of one long lens that could also do macro work, I would choose the lens you mention.
and what about Nikon AF 85mm F1.4 ? I saw some photos that has great bokeh using it and what about the sharpness ? is it still sharp at widest aperture ?
ricare recently posted..DOF Calculator For Blackberry
I’ve never used the 85mm f1.4 but I have used the f1.8 and that is definitely sharp enough.
I don’t think sharpness is an issue with portraits because the individual elements that make up the subject are so large compared to the total frame that they will look sharp even with a less than perfect lens.
Therefore any of the lenses I mentioned would be good enough to use wide open and I am sure the 85mm f1.4 would be excellent also except that I think it is a bit on the short side for portraits even for use on a DX camera body.
A much bigger concern is focus accuracy because the depth of field is so shallow with long focal length lenses. It doesn’t matter whether the lens is sharp if the point of focus is the end of someone’s nose and the eye is out of focus.
On a DX camera like the Nikon D90 for example, (that is, one with an AP-C size sensor) at f1.4 and taking a shot 6 feet (2 metres) from the subject, the depth of field is one and a half inches (3cm).
On a full-frame camera like the Nikon D700, the same set-up would give a depth of field of almost 2 inches (5cm).
That doesn’t give much leeway for getting the focus wrong, so you see that focus accuracy is very important and sharpness runs second to that.
Hmn yes, I agree with you. Focus accuracy is important since the DOF is very shallow at widest aperture.
ricare recently posted..How Much Do You Need Image Stabilisation On Your Lens/Camera ?
So I actually didn’t know the rule about distortion being only a function of distance from the subject. I was thinking it was a function of focal length.
If I’m understanding you right, I could use a 50 mm lens on a 1.6 crop factor camera and it would have the same distortion as an 80mm lens would have on a full frame sensor. Does that sound right?
TJ McDowell recently posted..Wedding Photography Tips To Get Amazing Images
Yes, that sounds right.
most portraits i tend to use either my Nikon 50mm f1.4 or my Nikon 70-200mm 2.8. Longer lens also means you can have a lower DOP without losing the sharpness of the main subject.
Andy recently posted..Maternity Portrait Photography and Pregnancy Photography
I am coming to the conclusion that the absolute best thing I like about my Nikon D700 is the viewfinder. I can see what is in focus.
I sold the D60, but there are plenty of shots taken with it that are elsewhere on this site. No direct comparisons though
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