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5 key points to know when choosing a cine lens

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When we start taking pictures, we soon realize how important it is to choose the right lens to accompany us in every situation. Among all the elements of our equipment, it is the cine lens that will be the star, we will spend the most time on it and even to choose it, we will pull out some hair…

You have to know which one to buy since it is not exactly one of the most economical photo accessories to put in your backpack.

And it will be just as decisive in providing quality and character to our images. Given all this, what are the elements to consider before buying one? We present here the 5 key points to choose your lens. \ 1. Compatibility of the lens with my camera

Choosing a cine lens that is compatible with your camera may seem obvious but it is not that obvious. Many photography enthusiasts who are just starting out often get caught up in a maze of trying to find the compatibility of the lens they want for their camera.

The brand

You may well have already clearly chosen the brand. If, for example, your camera is a Canon, then you will need an original Canon lens or a compatible cine lens, such as DZOFILM , Tamron, Samyang, Sigma… That is to say the brands that design lenses compatible with the most popular camera mounts on the market. So far, nothing complicated: an original lens or a lens compatible with your camera brand.

The mount

On the other hand, you need to know which mount it is: Canon EOS or Canon M? Let’s suppose you have a Canon EOS 1200D camera, you now know the brand and the mount (Canon EOS ) but what about the sensor?

The sensor

We must also ensure compatibility with the sensor. If we take the example of the Canon EOS 1200D camera, we will then be dealing with a camera with an APS -C sensor. A lens designed for cameras with a Full Frame sensor can therefore serve you, as well as a lens for cameras with an APS -C sensor. Click here to learn more about sensors.

But beware: if you are lucky enough to have a Full Frame camera, you will not be able to mount it on a lens designed for APS -C cameras because of two things: either it will not be possible to install it because of the design since it may clash with the camera mirror or simply, if you manage to install it, you will get images with vignetting.

This is because the amount of light that the lens can transmit is less than that of the sensor, so there will be parts of the image without information, without light (the edges). If we apply this combination, we can obtain something like the image below:

As mentioned, the reverse does not happen: a lens designed for Full Frame sensors will get enough light to an APS -C sensor. The only drawback is that you will lose information on the way and it would be a shame to invest in a Full Frame lens (more expensive) if it is not to be able to take advantage of it …

But with an FF lens, you will always have the assurance of knowing that you can always use it on APS -C as well as Full Frame cameras if you have several. And you will be able to switch from one to the other without any problem.

2. The focal length of the lens

The compatibility of the lens with your camera is the first step and the second is clear: what focal length to choose? Cameras usually come with a short zoom lens in the basic packages. You can decide to upgrade to a zoom lens with a longer focal range or take the plunge into fixed focal lengths. What do you think?

Zoom lens vs. fixed lens Should I choose a zoom lens or a fixed lens? There are two known principles here: zoom lenses are generally more versatile and convenient to use, while fixed focal length lenses are characterized by better optical quality.

On the other hand, fixed lenses are well known to better “train” photographers by forcing them to move around, in addition to giving unity to the angle of view if you are doing a photo series. This step is a very personal decision, many photographers usually have both options on their equipment and choose one or the other depending on the specific situation they will be facing.

Wide angle, telephoto… ?

We can also look at it from another angle: what kind of picture do I like to take? In other words, choose the focal length according to the main use you are going to make of it (it is not the same thing to make landscape as portrait, in the same way that the choice will be different if we talk about nature or studio photography).

So whether it’s a zoom or a fixed lens, you’ll know what type of lens you’re going to choose among the different possibilities: fish eye, wide angle, standard, telephoto or super telephoto.

Not sure which focal length is ideal for each case? No problem: take a look at the article where we explain everything about focal lengths and their uses, then come back here so that we can see together the other key points to take into account when choosing a cine lens.

3. The diaphragm, an important element of the lens

Another element that will largely influence the result of your photos and especially that of some specific types of photos, such as social photography, night photography and portraiture, is the maximum aperture. This subtle fact is decisive in the play of depth of field and brightness of the image.

Maximum aperture

The DZOfilm cine lenses with maximum apertures greater than or equal to f/2.8 are called “bright lenses” because they allow more light to pass through the sensor, but they are also known as “fast lenses” because by opening the aperture wider, you will have a greater shutter speed range.

A bright lens can help you in low light situations, such as night scenes or interiors, but also to achieve images with a shallow depth of field, which is quite useful and striking in some specific cases, such as portraits and foregrounds.

The number of aperture blades

Another aspect to take into account with regard to the diaphragm is the number of blades that compose it. In theory, it is said that the more blades, the better. Why? Because the quality of the bokeh is improved, since the blur is produced by defragmentations of light in perfect circles, unlike a diaphragm with few blades.

To obtain an almost perfect circle, we will mention diaphragms with at least 9 blades in their construction. Of course, this characteristic of the lens rightly increases its cost.

4. Does the lens have an image stabilizer?

Now we come to another important point in choosing a cine lens, namely whether it has an image stabilizer or not. This system consists of a set of lenses added that corrects the movement. You can even use up to 4 or 5 slower shutter stops without blurring the image. This is a real advantage when you find yourself in low light situations and you want to compensate for this by extending the exposure time.

Nikon calls this system IS (Image Stabilizer) while Canon calls it VR (Vibration Reduction). As for Tamron, it has chosen the name VC (Vibration Compensation). Be aware that you will have to face a higher budget if you decide for a cine lens with an image stabilizer.

If you choose a lens without image stabilizer and you face situations where you have to use shutter speeds slower than 1/60, then it is better to use a tripod but this is a “problem” that has a solution anyway…

5. Other specificities of the lens

In addition to the aspects already mentioned, lenses have other elements that may be important in your purchase decision. I have presented the most general elements, which are important for almost all types of photography, but what about if you want to practice a certain discipline?

If you want to take pictures of flowers or insects, for example, you will probably be interested in a lens with a macro function and a very short minimum focusing distance. And if, on the other hand, you want to shoot video, then you’ll be looking for a cine lens with a quiet focus motor or even a smooth and quiet aperture transition and integrated gear rings to accommodate a follow focus system.

This talk is part of the Photography series.

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