A colleague asked me recently: when would you/do you use a 24-70mm lens?

Here’s when: always.

That is to say: the 24-70 range is the most versatile range. Any type of portrait can be made in that lens range. Other lenses are great too, but none offer the versatility of a 24-70 on a full frame camera.

Here’s a recent simple portrait setup in a small room. This was intended for family pictures (the occasion was a Bat Mitzvah celebration):

Portrait setup

You can see:

1. A backdrop with a narrow white background paper roll
2. Two 400 Ws Bowens studio lights with umbrellas
3. A speedlight with a Honl speed strap and a Honl Photo 1/4″ Grid fitted to it
4. All lights are fired via Pocketwizards

I used a Canon 1Ds Mark 3 camera with the 24-70 f/2.8 lens set to f/8.

This gives me 50mm portraits:

Sisters (50mm)

And another one – where I ran out of space:

50mm group shot

This lens also gives me the ability to take 65mm portraits like this:

Portrait at 65mm

65mm group shot

Can you see these are closer up?

Photographers often say “you need 85mm or longer”. As a blanket statement this is nonsense. Plus, for much longer lenses I would have needed a larger room.

Now a few notes.

1. In all my numbers, I am taking about “real” lens length. If a lens is marked “50mm” or “24-70mm” this means “this lens is a 50mm lens or a 24-70 mm lens on a full frame camera”, i.e. on a camera whose sensor is the same size as a negative.
2. On a crop camera, a lens “behaves longer” proportional to the crop. So on a small Nikon camera (1.5 cop), a 50mm lens behaves like a 75mm lens, and a 24-70 like a 36-105. On Canon, the crop factor is 1.6. Still in the range!
3. You can use a 50mm fixed lens (or a 35mm fixed lens on a crop camera) to get this same 50mm effect. Affordable, small, and great quality.

I hope note 3 in particular inspires you to go get a prime lens or two.

For me, I also have a Canon 1D, with a 1.3 crop, and guess what? The 50mm is like a 65mm on that camera.

So I can put the 50 on the 1Ds to get 50, or on the 1D to get 65. Who needs zooms? Yes, the 24-70 is my lens of choice for these portraits, but sometimes it is nice to not zoom, and to work with one length instead.

I am often asked “Can I not just bring one 18-300 lens instead of bringing all these multiple lenses?”

Well, of course you can. There is some benefit from carrying just one lens. Convenience is important.

So why do we often forgo that convenience and use multiple lenses instead? What is the drawback to a “one does it all” type lens?

There are several.

1. Aperture. Your standard kit lens says “1:3.5-5.6” on the front. Or even “1:4.0-6.3”. That means when zoomed out to a wide angle, the lens can open its aperture to f/3.5 or f/4; and when zoomed all the way in, it can only go down to f/5.6 or f/6.3.
2. Sharpness. General purpose lenses tend to be less sharp than specialized lenses.
3. Distortion. General purpose lenses distort more at then far ends, and show more vignetting. They are neither a great wide angle lens nor a great telephoto lens.
4. The lens hood has to be the right shape for the widest angle, so at a zoomed-in setting, it will be less effective.
5. Size. They are big and heavy when they do not necessarily need to be – you always carry around your longest lens.
6. Build quality. These lenses tend to be less sturdy than “professional” lenses.

So the convenience comes at a cost. and the secret is to see when you need the benefits above, and when you do not. When you are on a vacation outdoors, a general lens may well do. But to take product photos, sports photos, night shots, or pictures for a magazine, I would go with a better lens.

Remember:the picture is not made by the camera, but by the lens (and by you!).