More on those lenses

Fast lenses, and why do you need them for portraits?

“Fast” lenses mean lenses with a large aperture, i.e. a low minimum “f-number”.  Like an f/2.8 lens, or even an f/1.4 lens. These lenses allow shallower depth of field, but they also allow in more light.

Imaging shooting in a studio. Like this, at today’s Imaging Show, at which I spoke about lenses again:

All sorts of lights, operated by Pocketwizards. Yes, true, you do not need a fast lens for this. A simple f/5.6 lens will do since you will shoot at f/5.6 – f/8. (Though a fast lens stopped down will be sharper than a slow lens wide open).

But. Imagine you want to shoot there using available light. Not the flashes, but the available modeling lights. Or perhaps window light in your room.

This you can do only if you have a fast lens. Set it to f/1.4 and it lets in so much light that in that situation above you can shoot at 1/100th second at 100 ISO (or if you wish,  1/400th second at 400 ISO):

Isn’t that amazing? handheld, Canon 7D, prime 35mm f/1.4 lens, set to f/1.4 at 400 ISO and 1/400th second. And it looks like a studio shot. Due to my use of a fast lens.

(Oh – why did I shoot as I was, at f/1.4 and 400 ISO? Because I was carrying a heavy bag with speedlights and lesens, and two cameras, and a laptop. So I had no spare hand. That’s why!)


Use the right tool.

“You can only use a 50-150mm lens for portraits”.

Nope. You can use any lens, just about. It’s a matter of matching the kind of portrait to the most suitable lens. Somewhat like this:

So you do not shoot a headshot with a very wide lens. But as you see, almost any type of lens can be used for portraits of one sort or another.

  • For stand-alone portrait, the longer the better. But you may not have space to use a 200mm lens.
  • For groups, wide or very wide is OK . Keep people away from the edges or they will stretch.
  • A Macro lens makes a good portrait lens.
  • For available light photos, you use a fast lens.
  • For environmental portraits, you use a wide lens, making sure your subject is not too large in the image.

I am going to be at the Henry’s Imaging show in Mississauga all three days, Friday to Sunday, talking about “the right lens for the job”. Come see me if you like!




Why you use good lenses

Lenses are worth the money you spend on them. At the risk of repeating myself, let me show you why.

A good lens focuses fast. It is well-built and strong. It has little aberration and edge distortion. It is silent. It has better coatings and resistance to flare. Most importantly, it has a larger aperture (a smaller “f-number”), hence more glass.

But also very importantly, it is sharper.

Look here. Click on this image and then click on “orginal size”, and then view it at original size. Make sure you follow all those steps.

(24-70 lens at 24mm, at f/8, 1/125th second, 100 ISO; using studio strobes).

When you do that, you basically get to DNA-level.

“But I do not want my face to be so sharp!”.

Yes you do. You want your eye, eyelashes and soon, to be sharp. Skin you can blur later if you wish, but the basic image must be sharp.

And that is why a good lens (e.g. in the Canon-world, an “L”-lens, where “L” stands for “Luxury) is worth every penny. (And they cost a lot of pennies – but the lens will last you twenty years, both technically and in economic terms).

I am repeating myself, I know – but this is important. In lenses, there are few shortcuts (except an affordable 50mm lens, which is why if you do not yet have one, go get one now!)

Aperture effect

Here’s an effect we forget sometimes. When a lens is wide open, it vignettes.

My 50mm lens at f/1.2:

And here is that same lens a stop and a third closed down, at f/2.0:

Can you see the difference? The first picture, wide open, shows significantly more vignetting.

Now I like vignetting – a lot, in portraits. But shooting portraits with a lens wide open is rather dangerous, since depth of field is very shallow and may not be sufficient. So I add vignetting in Lightroom – Post Crop Vignetting is one of the best controls in Lightroom for when you are shooting portraits.

And when you are not shooting portraits, avoid vignetting like this – so in those cases, avoid shooting with your fast lens wide open.

The SUV of lenses

I like to shoot with many lenses. Wide (16-35 on full frame), long (70-200 on crop), and fast primes.

But the one “general purpose” lens I keep going back to is the 24-70 f/2.8L. First of all, this lens is sharp:

Michael Willems - self portrait, detail

Self portrait, detail (view at full size)

You like crazy sharp? This lens is crazy sharp.

The main thing about this lens, however, is that it can be used for almost any shoot. For instance, for music school portraits like today’s:

Michael Willems - demo portrait

Michael Willems - demo portrait

But also for headshots, environmental portraits, events, travel, low-ish light shots, and much more. Its fast speed (i.e. the low f-number, a constant 2.8 throughout its zoom range) allows you to blur backgrounds well, and allows its use in low light. This is why photojournalists keep that lens in the bag and on the camera.

Today’s shoot was a music school and tomorrow’s is the same – all day. If you wonder how the shots above were lit: three Bowens studio lights; an umbrella, a softbox and a snoot. Here’s the softbox:

Softbox during music school shoot

Softbox during music school shoot

A softbox gives you a large area and hence soft light. For studio I use a large softbox; for on-the go shoots I use the Honl Traveller 8 softbox on a speedlight. (As you know, Dave Honl will be helping me teach a course in Toronto on March 19; he is in London today, where yesterday he taught a course to Matteo, a young friend and student who has taken a number of my courses. Small world!)