Pho­to: Pho­tos by Lan­ty / flickr.com

Buy­ing your first lens is a great joy, but also a great respon­si­bil­i­ty.

Many cam­eras are imme­di­ate­ly sold with a lens in the kit (such lens­es are called “whale lens­es”) — this is a good option to start your cre­ative jour­ney. But if you want to unleash the full poten­tial of your cam­era and your own cre­ativ­i­ty, at some point you will have to con­sid­er buy­ing one or two addi­tion­al lens­es. The new “glass” (as pho­tog­ra­phers call lens­es) will help improve image qual­i­ty or start shoot­ing in a new genre.

How to choose the right mod­el, giv­en the vari­ety of options avail­able? In this guide, we will go over the main spec­i­fi­ca­tions to look out for before buy­ing your first lens.

Lens name

For begin­ners, the names of lens­es are incom­pre­hen­si­ble abra­cadabra. For­tu­nate­ly, you can ignore most of the obscure let­ters and num­bers, but a few of them are very impor­tant. They indi­cate the most impor­tant char­ac­ter­is­tics, which we will con­sid­er.

  • For­mat — the size of the sen­sor for which the lens is designed.
  • A mount is a lens mount that deter­mines if a giv­en lens will fit your cam­era.
  • Focal length is a para­me­ter that affects how wide or enlarged the image will be.
  • Aper­ture — denot­ed by “F” or “f /” and deter­mines how fast the lens will be and how much it can blur the back­ground.
  • Image sta­bi­liza­tion — some mod­els help sta­bi­lize the image to get rid of “shake” when shoot­ing hand­held.
It is easy for a begin­ner to get lost in a bunch of num­bers and spe­cial sym­bols, but in real­i­ty every­thing is not so dif­fi­cult.

Matrix and lens

The same lens on cam­eras with sen­sors of dif­fer­ent sizes will show dif­fer­ent pic­tures.

Today, the most pop­u­lar cam­eras on the mar­ket are those with three main sen­sor sizes: 4:3, APS‑C and full-frame. The largest for­mat is full frame, APS‑C is small­er, and 4:3 is even small­er.

When choos­ing a lens, it must be borne in mind that some glass­es only work with cam­eras of a cer­tain for­mat. Quite often, cam­era man­u­fac­tur­ers make the same mount for their APS‑C and full frame cam­eras.

At the same time, in most cas­es, full-frame lens­es work fine on APS‑C cam­eras, but APS‑C lens­es lim­it full-frame cam­eras to shoot­ing in cropped (cropped) APS‑C mode.

You can find out for which for­mat this lens is designed from the name. You will find the main des­ig­na­tions in the table below.

Some­times pho­tog­ra­phers start with cheap­er APS‑C cam­eras but buy full-frame lens­es that will be com­pat­i­ble with the full-frame cam­era they plan to pur­chase in the future. We advise you to use lens­es that suit your needs today, not those that will bet­ter suit your dream cam­era.


Each cam­era man­u­fac­tur­er uses its own bay­o­net mount, which makes one brand’s lens­es not suit­able for anoth­er brand’s cam­eras: for exam­ple, Canon lens­es will not fit a Nikon cam­era and vice ver­sa.

How­ev­er, there are excep­tions for 4:3 cam­eras, which are joint­ly devel­oped by Pana­son­ic and Olym­pus, as well as for the L‑mount, which is com­pat­i­ble with full-frame cam­eras from Leica, Pana­son­ic and Sig­ma.

Most com­pa­nies today have focused on mir­ror­less cam­eras and lens­es for them. How­ev­er, many DSLR lens­es work with mir­ror­less cam­eras from the same brand via an adapter. Mir­ror­less lens­es do not work with SLR cam­eras.

Bay­o­net Cam­era type Matrix For­mat Pecu­liar­i­ties
Canon EF Mir­ror full frame
EF‑S Mir­ror APS‑C Canon EF‑S lens­es are not com­pat­i­ble with the com­pa­ny’s full-frame SLR cam­eras, but APS‑C EF-mount lens­es from oth­er brands are.
EF‑M Mir­ror­less APS‑C EF and EF‑S lens­es work with EF‑M cam­eras via adapter
RF Mir­ror­less full frame Most EF lens­es work with RF cam­eras via an EF/RF adapter
4:3, Olym­pus, Pana­son­ic Micro 4:3 Mir­ror­less 4:3
fuji­film X Mir­ror­less APS‑C
Bay­o­net L, Leica, Pana­son­ic, Sig­ma L Mir­ror­less Full frame, APS‑C (TL) Cam­eras and lens­es with TL mount (APS‑C) are made only by Leica
Nikon F Mir­ror full frame Only mod­ern AF‑S lens­es sup­port aut­o­fo­cus when used with Z mir­ror­less cam­eras
Z Mir­ror­less Full frame, APS‑C (DX)
Pen­tax K Mir­ror Full frame (FA), APS‑C (DA) As with Nikon, there are K‑mount options, but most lens­es work with the lat­est DSLRs.
Sony E Mir­ror­less Full frame (FE), APS‑C (E) Oth­er lens man­u­fac­tur­ers use the E des­ig­na­tion in the name for both APS‑C and full frame lens­es, so it’s worth check­ing which for­mat they cov­er.

A num­ber of third par­ty man­u­fac­tur­ers, includ­ing Tam­ron, Tok­i­na and Sig­ma, make lens­es for cam­eras from oth­er brands. Most options are avail­able for DSLRs.

Sony allows third-par­ty man­u­fac­tur­ers to make lens­es for its mir­ror­less E sys­tem, unlike Nikon and Canon — there are very few third-par­ty options for their mir­ror­less Z and RF sys­tems.

Focal length

The first num­ber in the name of a lens is its focal length. Com­bined with the size of the sen­sor, it deter­mines the “angle of view” of your lens. The small­er the val­ue in mil­lime­ters, the wider the view­ing angle you get. Zoom lens­es use two num­bers that indi­cate the max­i­mum and min­i­mum focal lengths avail­able for that mod­el. For exam­ple, a typ­i­cal kit zoom lens has a focal length of 24–70mm. Lens­es with a fixed focal length (“fix­es”), which do not know how to zoom, have only one num­ber in the des­ig­na­tion, for exam­ple 50mm.

In the image below, you can see how the pic­ture changes depend­ing on the focal length. At the same time, the small­er the matrix for­mat, the nar­row­er (cropped / cropped) view­ing angle will be obtained. As a result, the focal lengths that you use with a cam­era of one for­mat will be dif­fer­ent from those that you need to use for the same pur­pose on a cam­era of anoth­er for­mat.

How the pic­ture changes depend­ing on the focal length of the lens. Pho­to: Dave Black / nikonusa.com
Lens type 35mm (full frame) APS‑C 4:3
ultra wide angle 24 mm and wider 16 mm and wider 12 mm and wider
wide angle 28 mm 18 mm 14 mm
Nor­mal 50 mm 30 mm 25 mm
Long throw (tele­pho­to) 80 mm and longer 55 mm and longer 42 mm and longer

When talk­ing about the focal length of a lens, a val­ue often used is the 35mm (full frame) equiv­a­lent — the so-called equiv­a­lent focal length (EFF). For exam­ple, an 18–55mm kit lens for an APS‑C cam­era would have an EGF of 28–90mm.

This means that an 18–55mm lens on an APS‑C for­mat cam­era cov­ers the same angle of view as a 28–90mm lens on a full frame cam­era.

Zooms and fixes

From left to right: adapter, prime and zoom lens Canon EF‑M. Pho­to: decltype / commons.wikimedia.org

At first glance, zoom lens­es are an extreme­ly con­ve­nient thing, and buy­ing a prime lens may seem strange.

But fix­es still have a num­ber of advan­tages:

  • small­er size and weight;
  • more aper­ture;
  • sharp­er pic­ture.

This makes primes the pre­ferred option for some appli­ca­tions, such as shoot­ing in low light or for por­traits with pro­nounced bokeh.


Aper­ture deter­mines how much light a lens can cap­ture, or, in oth­er words, its aper­ture ratio. Aper­ture val­ues ​​are record­ed in one of the for­mats: F4, f / 4 or 1: 4 — all this means the same thing.

The small­er the f/number, the larg­er the aper­ture and aper­ture of the lens. For exam­ple, an aper­ture of f/2.8 lets in twice as much light as f/4.

Aper­ture stops

f/1.4 f/2.0 f/2.8 f/4.0 f/5.6 f/8.0 f/11 f/16

Pop­u­lar aper­ture val­ues ​​that are one “stop” or “step” away: from left to right, each suc­ces­sive val­ue lets in half as much light as the pre­vi­ous one.

A lens with a larg­er max­i­mum aper­ture (small­er f/number) can shoot in low­er light and take indoor pho­tos with­out a flash. The aper­ture val­ue affects the depth of field — the area of ​​​​the pho­to in which the sub­ject will be clear, not blur­ry. This is an impor­tant aspect for por­trait and cre­ative pho­tog­ra­phy.

The faster your lens, the more blurred the back­ground can be — this helps to high­light the sub­ject. Pho­to: maxpixel.net

Longer lens­es give a shal­low­er depth of field for the same aper­ture val­ue and when focus­ing at the same dis­tance. To achieve the same shal­low depth of field on APS‑C and 4:3 cam­eras as on full-frame cam­eras, you will needaboutbig diaphragm.

Lens­es are des­ig­nat­ed by their max­i­mum aper­ture. If the lens is labeled with an aper­ture range (e.g. f/3.5–5.6), these are the max­i­mum aper­tures at the wide end and tele­pho­to end, respec­tive­ly. You can always low­er the aper­ture size (close the aper­ture) if you need more sub­jects to be in focus.

Usu­al­ly, the larg­er the lens aper­ture, the more expen­sive it is. For most sit­u­a­tions, you’ll be fine with a max­i­mum aper­ture around f/3.5. For por­traits with pro­nounced bokeh, fix­es from f / 1.8 are best suit­ed. There are also super fast glass­es with f/1.0 and even low­er — they are a real rar­i­ty and are very expen­sive.

These rec­om­men­da­tions are valid for full frame sen­sors. If you have a crop, you need to remem­ber that the larg­er the matrix, the more light it cap­tures. Accord­ing­ly, cam­eras with a small­er matrix need a faster lens. So you can take bet­ter pic­tures when shoot­ing in poor light­ing.

Image stabilization

The image sta­bi­liza­tion sys­tem allows you to get sharp­er shots when shoot­ing hand­held, min­i­miz­ing the “shake” and jud­der in the frame.

Some­times there is a built-in sta­bi­liza­tion sys­tem in the cam­era itself (in the “car­cass”), but many lens­es are equipped with their own opti­cal sta­bi­liza­tion sys­tem. Such sys­tems are espe­cial­ly effec­tive with tele­pho­to lens­es, for which the built-in sta­bi­liza­tion in the cam­era usu­al­ly does not work effec­tive­ly. Many cam­eras can com­bine the built-in sys­tem in the body and the opti­cal sys­tem in the lens for even more effec­tive cor­rec­tion.

Dif­fer­ent man­u­fac­tur­ers of sta­bi­liza­tion sys­tems are called dif­fer­ent­ly. For them, dif­fer­ent des­ig­na­tions are used in the name of the lens­es:

  • Canon-IS;
  • Fuji­film and Pana­son­ic — OIS;
  • Nikon — VR
  • Sony OSS;
  • Sig­ma-OS;
  • Tam­ron-VC.

A small summary

So, when choos­ing a lens, you need to pay atten­tion to its for­mat and mount — they must be com­pat­i­ble with your cam­era.

Next, you need to fig­ure out the main char­ac­ter­is­tics that you need: focal length and aper­ture (max­i­mum aper­ture). Decide whether you want zoom or prime, whether you need image sta­bi­liza­tion — it is not so impor­tant if your cam­era itself is equipped with this func­tion.

We will talk more about pop­u­lar lens types and some addi­tion­al features/features in our next arti­cle.

* when prepar­ing the arti­cle, mate­ri­als from the resource dpreview.com were used