If you had to choose between a good camera or a good lens, what would you choose? Many of us would naturally go to for the camera body, full of gadgets and innovation. However, it is not necessarily the best choice.

The lens is the centerpiece of your camera: it is the lens that allows you to capture the light. Put a lousy lens on an excellent camera, and you soon realize that your body won’t reach its full potential. The opposite is also true to a lesser extent, and there is no point in putting a very high-end lens on an entry-level body.

The lens is the element which has the most significant impact on the quality of your picture (sharpness, contrast, resolution). It is characterized by its focal length (in mm), its aperture, and its viewing angle. The offer is overwhelming, and the choice of one or more lenses depends on the type of photography you are going for – sport, landscape, portraits, reportage – and of course your budget.

Remember: it is always better to use a good lens, especially since, unlike the camera body, whose technology is evolving very quickly, the objective is a sustainable investment with little obsolescence.

APS-C or Full Frame?

Before going any further, you need to think about one important point: will you use an APS-C camera or a full-frame camera? This question is crucial because it determines your lens choice. Each brand offers lenses dedicated to APS-C (and incompatible with a 24×36 body) as well as a full-format range that works with both full frame and APS-C sensors.

Optics compatible only with APS-C camera are often low-priced and with sufficient quality for this type of sensor.

On the other hand, if you want to use a full-frame SLR, you need to buy compatible lenses, often more expensive and heavier but ensuring optimal quality.

Here are the abbreviations used by the leading manufacturers:

  • Canon: EF-S for APS-C / EF for 24×36
  • Nikkor: DX for APS-C / FX for 24×36
  • Sigma: DC for APS-C / DG for 24×36
  • Tamron: Di II for APS-C / Di for 24×36
  • Tokina: DX for APS-C / FX for 24×36
  • Pentax: DA for APS-C / D -FA for 24×36
  • Fujifilm: XC or XF, both in APS-C format

The focal length

The focal length is expressed in millimeters and designate the distance between the sensor of the body and the optical center of the lens. This focal length affects the magnification of the subject and the viewing angle. The shorter the focal length, the wider the viewing angle. For example, 16mm results in a very wide-angle, and a 400mm in a small angle of view (close-up).

There are two categories of lenses: the fixed focal length lenses and the variable focal length lenses (zoom). For example, a Canon 24-105 f/4L lens has a focal length ranging from 24mm (wide angle) to 105mm (small telephoto lens). A zoom is often more convenient to use, especially when it is not possible to move around the subject, but the quality of a fixed lens is usually much better.

Advantages of fixed focal lengths

  • Quality: Zooms have improved considerably, but for the same budget, a fixed focal length produces sharper and more precise images.
  • Price: Fixed focal lengths are generally cheaper, which seems logical since they are way easier to make. There are of course expensive fix lenses but only in the professional range. The 50 mm f/1.8 is known to be extremely cheap and yet offering fantastic quality.
  • Weight: Also due to their simpler design, fix lenses are lighter. Do not underestimate this point especially when traveling.
  • Maximum aperture: They generally have a greater maximum aperture than zooms.
  • Creativity: It may be more personal and a little less objective, but by forcing you to move to frame correctly, a fixed focal length forces you to be more creative and find other angles of view.

Advantages of zooms

  • Versatility: Zooms cover a broader focal range, they allow you to take pictures of several different types. Depending on the lenses you take with you in your bag, they can even be an advantage in terms of weight and cost. Like I said before a zoom is often more convenient to use, especially when it is not possible to move around the subject.

The focal length of a lens is given for a 24×36 sensor (silver SLR or high-end DSLR such as the Canon 1DX and 5D, or the Nikon D4s and D800). On most DSLRs, the sensor size is smaller than a 24×36, so the crop factor enlarges the final image. This crop factor is 1.6x for Canon and 1.5x for Nikon.

Let’s see with simple examples: On a Canon APS-C body (example 80D or 7D MK II), a lens with a focal length of 200mm becomes 200×1.6 = 320mm. Depending on the type of photo you are going for it can turn as an advantage (users of long lenses for shooting sports, animal photos), or disadvantage (amateurs of wide angles a 14mm becomes a 22mm).

This focal length allows you to define lens categories:

  • Standard: It simply means that what you see in the lens corresponds approximately to what you see with your eyes. The focal length corresponding to the human eye is about 50 mm (full-frame), and 35 mm for a crop sensor. Basically, all lenses with a focal length of approximately 35 to 85 mm fall in this category. Kit lenses usually are 18-55 mm, which covers this category and even a little bit of the next one, so beginners can photograph a wide variety of subject.
  • Wide angle: Optics of 28 mm or less fall in this category. This type of lenses is handy for landscape photography for instance.
  • Telephoto lenses: Anything above 100 mm. Useful for sport, animal, portraits photography. After 300mm, lenses fall into the super-telephoto category.

The different types of lenses

Wide angle, 50mm, telephoto lens? The choice of an objective depends on the use you want to make of it. Here is a summary of what each type of lens can do for you:

  • Wide angle: Photojournalism, nature and landscape, concerts, people and everyday life.
  • 50mm: portrait, street photography, studio, still life, people and life scene. A 50mm (on a full-frame camera) corresponds roughly to human vision.
  • Standard zoom: Versatile, photojournalism, wedding, family use.
  • 85mm: Portrait, wedding, studio, close-up.
  • Zoom telephoto lenses: Versatile for sports, wildlife, concerts, weddings. A 70-200 lens set at 200mm allows, for example, to isolate a subject with a shallow depth of field.
  • Fixed telephoto lenses: Sport, portrait, animal, concerts, shows. Higher quality zoom, but less flexible to use. When using a fixed lens, you need to know what you are going to photograph!
  • Tilt-shift lenses: Architectural photography, creativity. This type of lens allows you to correct the perspective and depth of field. Usually, very expensive very few photographers own one. Although they are made for a very particular use, they are fun to play with and renting one for a day could be a great idea.
  • Macro lens: Photography very close to the subject, animal, insects, still life.

The Aperture

An f/n value indicates the maximum aperture of each lens, which determines how far the lens diaphragm can open. In other words, the larger the opening, the better the lens in low light condition and the shallower the depth of field.

On most zoom lenses, the focal length varies: a Canon 70-300 f/4.5-5.6 has an aperture of f/4.5 at 70mm and an aperture of f/5.6 at 300mm.

The high-end zoom lenses often offer a constant aperture – like the Canon 70-200 f/2.8. Although it offers you great flexibility, it is a complex and expensive technology.

The maximum aperture you need depends on the situations in which you are shooting:

  • Indoors, especially in dimly lit situation (concerts), f/2.8 or more is a great choice.
  • For covered days, especially in conditions where you need to use fast shutter speed, you can settle for f/4 or faster.
  • Finally, in sunlight, any opening could do the job.

The image stabilizer

Some lenses offer an image stabilizer. Every manufacturer has it owns abbreviation: IS (Image Stabilizer) for Canon, VR (Vibration Reduction) for Nikon, OS (Optical Stabilizer) for Sigma, or VC (Vibration Compensation) for Tamron. These technologies work with sensors located inside the lens that detect and measure the mechanical vibrations caused by the photographer. The system then compensates for these vibrations by moving a group of lenses that stabilizes the image.

Depending on the photographer, it is possible to gain 1 to 4 Stops: for example with a 200mm, rule of thumbs state to shoot at a minimum 1/200 sec to avoid blur. With the active stabilizer, you can easily go down to 1/50 while being sharp.

The minimum focusing distance

A lens has a minimum focusing distance, for example, 1m20 on a Canon 70-200 2.8 L IS II. Below this distance, it is impossible to focus and therefore obtain a sharp subject. You have to take care of that especially if you are into macro photography. In this case, you should look for macro lenses which allow you to focus way closer to your subject.

Tips: Choose lenses with ultrasonic autofocus, a technology that offers fast and quiet focusing: it is called USM for Canon, AF-S for Nikon, HSM for Sigma, SDM for Pentax, SWD for Olympus, or SSM for Sony.

The brand

Although you can’t put a Nikon lens on a Canon body, third party brands such as Sigma and Tamron make lenses for both systems. Sometimes these manufacturers offer lenses with a much better Quality/Price ratio than the “big” brand, and when looking for a new lens, you should definitely check their offers. Often, the quality difference is minimal, but the price difference is significant.

The jungle of acronyms

Canon lens acronyms (example: Canon EF 70-200mm f/2.8 L IS USM)

  • EF for Electronic Focus. Canon lens mounts compatible with all Canon SLRs (since 1987) regardless of the sensor size.
  • EF-S for Electro Short Back Focus: A Canon mount designed since 2003 for APS-C crop sensor. Incompatible with 24×36 and APS-H (1D, 5D) enclosures.
  • IS for Image Stabilizer: Lens equipped with an optical stabilization system.
  • L: L for Luxury. A Canon L-Series lens is a very high-end lens for professionals or demanding amateurs.
  • USM for Ultra Sonic Motor: Autofocus (AF) lens with a fast and quiet “Ultra Sonic” motorization.
  • UD for Ultra-Low Dispersion: Lenses with a very low dispersion which reduces chromatic aberrations.
  • DO for Diffractive Optics. A DO lens has different lenses to reduce weight and chromatic aberrations significantly.
  • TS-E for Tilt-Shift Enabled: Shifting and tilting lens. Allows you to correct the perspective and depth of field. Ideal for architectural photography.

Nikon lens acronyms (example: Nikon AF-S 70-200mm f/2.8 ED VR)

  • DX Digital: A Nikon mount for crop sensor. Incompatible with 24×36.
  • VR for Vibration Reduction: Lens equipped with an optical stabilization system.
  • AF-S for AutoFocus Silent Wave Motor: Lens with Autofocus (AF) with a fast and quiet “Silent Wave” motorization.
  • AF-I for AutoFocus Internal Motor: Lens with internal Autofocus.
  • ED for Extra-Low Dispersion: Lenses with a very low dispersion which reduces chromatic aberrations.
  • PC for Perspective Control: Shifting and tilting lens. Allows you to correct the perspective and depth of field. Ideal for architectural photography.
  • IF for Internal Focusing: internal focusing system. With the IF the front lens remains fixed and does not rotate.

Sigma lens acronyms (example: Sigma 24-70mm f/2.8 DG EX HSM)

  • DG DiGital: Lens optimized for digital cameras, but also compatible with a 24×36 silver SLR.
  • DC Digital Camera: Lens designed for small sensor cameras (Canon APS-C, Nikon Dx). Incompatible with 24×36 body.
  • OS Optical Stabilizer: Lens equipped with an optical stabilization system.
  • APO: Lenses with a very low dispersion which reduces chromatic aberrations.
  • HSM Hyper Sonic Motor: Autofocus (AF) lens with a fast and quiet “Sonic Motor” motorization.
  • EXCELLENCE: Lens with superior performance. An equivalent of the Canon L series.

Tamron lens acronyms (example: Tamron SP 17-50mm f/2.8 XR Di II VC)

  • Di for Digitally Integrated Design: Lens optimized for digital cameras, but also compatible with a 24×36 silver SLR.
  • Di II for Digitally Integrated Design II: Lens designed for small sensor bodies (Canon APS-C, Nikon Dx). Incompatible with 24×36 body.
  • XR for Extra Refractive Index Glas: High-end lens using high refractive index lenses.
  • USD for Ultrasonic Silent Drive: Autofocus (AF) lens with a fast and quiet “Ultrasonic” motorization.
  • VC for Vibration Compensation: Lens equipped with an optical stabilization system.
  • LD for Low Dispersion: Lenses with a very low dispersion which reduces chromatic aberrations.
  •  SP for Super Performance: Lens with superior performance. An equivalent of the Canon L series.

Sony lens acronyms (example: Sony 24-70mm f/2.8 ZA SSM)

  • DT: Lens designed for small sensor housings. Incompatible with 24×36 boxes
  • SSM for Super Sonic Motor: Autofocus (AF) lens with a fast and quiet “Super Sonic” motorization.
  • APO: Lenses with a very low dispersion which reduces chromatic aberrations.
  • G: Top-of-the-range professional quality lens
  • ZA: Autofocus lens mount designed by Carl Zeiss for Sony.

Pentax lens acronyms (example: Pentax DA 50-135mm f/2.8 ED AL IF SDM)

  • DA: Lens designed for small sensor housings. Incompatible with 24×36 body.
  • SDM for Super Direct-drive Motor: Lens with Autofocus (AF) with fast and quiet motorization.
  • IF Internal Focus: Lens with internal focus. With the IF the front lens remains fixed and does not rotate.
  • AL for Aspherical Lens: Lens equipped with aspherical lenses.
  • ED for Extra-low Dispersion: Lenses with a very low dispersion which reduces chromatic aberrations.

Lenses suggestions

You can find in the tables below, the most relevant choices according to the brand of your camera, your desired focal length and your camera body type (APS-C or Full-Frame). It is by no means an indication of what you should buy but rather a list of suggestions that you should investigate before taking a choice.

Canon Lens suggestions:

Canon Lenses Guide
Canon Lens Guide

If your budget is tight, for less than 100$ the 50mm f/1.8 from Canon is an excellent choice, just like the Tamron 17-50 2.8 which despite the somewhat indiscreet noise of its engine during the focusing remains a relevant choice for less than 300$. If, on the other hand, your budget is not an issue, turn to the L series to get the best from Canon.

Nikon Lens suggestions:

Nikon Lenses Guide
Nikon Lens Guide

A little more expensive than Canon, Nikon’s 50mm f/1.8 is an excellent choice for small budgets (about 140$), as is the Tamron 17-50 2.8.

Pentax Lens suggestions:

Pentax Lenses Guide
Pentax Lens Guide

Sony Lens suggestions:

Sony Crop Sensor Lenses Guide
Sony Crop-sensor Lens Guide
Sony Full Frame Lenses Guide
Full-frame Lens Guide

Sigma Lens suggestions:

Sigma Lenses Guide
Sigma Lens Guide

Tamron Lens suggestions:

Tamron Lenses Guide
Tamron Lens Guide

One word on neutral density filter:

When you use your lens in a place where conditions are difficult (dust, mud, water droplets, sand, seaside) or if you want to protect the front lens against scratches and unfortunate impacts permanently, there are neutral filters. Neutral? Not entirely, since a protective filter transmits about 99% of the light received and can act minimally on the color temperature. To the naked eye, of course, this remains invisible, and the most important thing is to protect your lenses. There are several neutral filter models to choose from, depending on the diameter of your lens (from 37 to 82 cm) and the quality of the glass. Just avoid buying a low-end filter on a 2000$ lens and vice versa.