Backgrounds and sharpness and white balance: oh my!

I thought I would chat about some of the things that go through my mind when doing a portrait, like this one last night:

Questions like:

  • What camera and lens? In this case, the Canon 7D and a 50mm f/1.4 lens.
  • What settings? Well, manual at 100 ISO, 1/125th second, f/5.6 is my standard start point, as it was here.
  • What lighting setup? In this case, a standard two main lights (softbox main light on camera left, umbrella fill light on camera right) with a snooted hair light behind left, and a gridded gelled background light. Note that while the main lights were monolights, the background light was a small speedlite fired by a pocketwizard through a Flashzebra hotshoe cable.
  • What lighting ratio? In this case pretty flat, but usually more like a 3:1 key:fill ratio.
  • What body position? Usually angled, in this case toward the softbox.
  • What head position? In this case, straight on since the subject wanted it that way.
  • What colour background? In this case I used a blue-green gel from the new Honl Photo “Autumn” colour gel set.
  • What viewpoint? I carefully choose this by moving myself left and right, up and down, until the person looks best to me for the portrait wanted. If in doubt, I take multiple views and choose later.
  • What white balance? I set it to “Flash”, even when shooting RAW, just so I get OK views on the back of the camera.

That’s all there is to a quick snap like this, which took a few minutes – if that.


Photography is about composition/subject + moment + light. I reckon I got several of these right here:

From earlier this year. Using a 35mm lens on a 1.3 crop camera (meaning it’s 50mm), set to f/2.8 at 1/160th second.

Moral of the story: a “standard” lens is great. This is equivalent to a 50mm lens. Do take lots of pictures and do not forget the “moment” aspect.


Portraits? Then use a 50mm f/1.8 lens (affordable, fast, sharp) and shoot in Aperture (A/Av) mode with it wide open (preferably by window light).

Look at this recent available-light shot of a student:


This gets you the dual advantages of low-light ability (no flash needed!) and blurry backgrounds. As long as you make sure the closest eye is the sharpest.

So, set your camera to the widest aperture (the smallest F-number), use high enough ISO (indoors this might be 400-800 ISO), and use one focus spot, and aim that spot at the closest eye. Click!

Do I need a fast lens?

When students ask me “should I really buy a fast lens?” (For beginners, that’s a lens with a low “F-number”, like f/2.8), my answer is “it depends.”

What are you shooting? Landscapes (no need for a fast lens, since you will shoot at f/16 or above) or nightclubs (which need a fast lens for low-light abilities), portraits (which need a fast lens for blurry backgrounds) or sports (which need a fast lens for fast exposures)?

And if you like blurry backgrounds, does it make sense to get a pro lens like an f/2.8, or is my kit f/5.6 lens enough? That’s an easy one to answer. It depends. On whether you like this, taken yesterday during a course at f/5.6:


..or whether you prefer the same shot at f/2.8:


You decide. View them full size to really see the difference.

Know that every stop faster (from 5.6 to 4, or from 4 to 2.8) doubles the lens price. But if you like the blur (“Bokeh”) in the bottom shot, there’s no substitute for fast.

And I did not say expensive – at least not necessarily so: while some lenses like my f/1.4 35mm cost $2,000, an excellent 50mm fixed (“prime”) f/1.8 lens (a “nifty fifty”, which on a crop camera is  great portrait lens) can be had for as little as $150 or less.

So yes, low f-numbers make a difference and that’s why photographers are willing to pay lots of money for them. But don’t worry: good lenses keep their value.

f/1.8 lens, stopped down, shot with f/1.4 lens, open

I have many times recommended 50mm f/1.8 lenses, and I’ll try to inspire you once more to go out and get one right now. Most manufacturers have a cheap lens like this:


As you will have heard me say many times, this lens is cheap, small, light, fast and sharp.

Ideal for portraits or for low-light subjects or images where you want to dramatically blur the background. If this lens is not in your kit yet, I recommend you add it immediately.

As you will have seen in the previous post, I shot Prof Dawkins yesterday with just sich a lens (my 50mm f/1.4).