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What is a Fast Prime Lens

What is a fast prime

A fast prime lens combines a fixed focal length (no zoom) with a large fast aperture. As a result, fast primes tend to be smaller and more affordable whilst delivering vastly superior image quality.

On the other hand, you lose the versatility of being able to zoom in and out. While this may sound like a difficult compromise, fast primes are the best choice for many kinds of photography and a great way to develop your skills as a photographer. In this post, we look at fast primes and the 5 reasons why you need one. Jump to Conclusion

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The definition of a fast prime lens

A fast prime lens has two defining characteristics – a fixed focal length and a larger aperture.

Fixed Focal Length

A fast prime lens features a fixed length. In other words, you are unable to zoom in or out. Whilst this may seem like a show stopper, fast prime lenses are the best option for many kinds of photography.

For instance, if you shoot portraiture, macro, or any other kind of photography where you have full control of the distance between you and your subject, a prime lens will give you a far sharper image for less money. In fact, I use a 50mm as my everyday lens whilst my heavier zooms sit at home waiting for their moment in the sun.

Large Aperture

Fast Primes feature large apertures enabling more light to pass through your lens towards your camera’s sensor. Because your camera is getting more light, you can avoid camera shake by using faster shutter speeds and suffering less motion blur when shooting moving subjects.

Best of all, larger apertures produce a shallower depth-of-field. Therefore, you get to melt those backgrounds into a glorious goo.

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5 Advantages of a fast prime lens

Sometimes, you need a zoom but here are 5 reasons why you might prefer to use a fast prime lens.

1. Image Quality

Fast primes have superior image quality to comparable zoom lenses. In fact, in terms of image quality, a budget 50mm lens will out-perform a thousand-dollar zoom.

Fast prime lenses deliver superior image quality because they lack the complexity of zoom. In other words, a fast prime can be designed to excel at its one and only focal length. On the other hand, a 24-70mm zoom lens has to be good enough throughout its whole range.

2. Larger Apertures

Fast primes such as the humble 50mm feature large F1.8 apertures that pass 8-times more light than the F5.6 aperture within many kit lenses.

As a result, you can use faster shutters speeds to avoid camera shake-induced blur whilst avoiding high image-degrading ISOs. What is ISO

Of course, you can get zoom lenses with large apertures. For example, pro-grade zooms such as the Nikon AF-S 24-70mm feature large F2.8 apertures. Yet these sorts of lenses are large, heavy, and cost thousands of dollars.

But if you can live with a fixed focal length, you can buy a cheap, compact 50mm prime lens with an even bigger aperture for just a hundred bucks.

3. Size

Fast primes are much smaller than comparative zoom lenses. If you find yourself using your zoom at the same focal lengths, you might be able to shred a little weight by using prime lenses instead.

4. Background Blur

Because fast primes have large apertures, they are better able to blur those backgrounds. If you’re still shooting portraits with your kit lens, try stepping up to cheap background-melting 35 or 50mm F1.8 prime. Trust me, you’ll never go back. I didn’t.

5. Price

Even a cheap 50mm fast prime will deliver the pro-grade image quality and background blur. Unfortunately, you’ll need to spend thousands to get an equivalent zoom lens.

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What are fast prime lenses used for

Fast primes tend to be used in situations where you can control the distance between you and your subject. For example, 35mm lenses tend to be handy for street photography whilst I like to use a 50mm as my everyday lens.

On the other hand, super-sharp background-blurring 85mm primes are ideal for portraiture whilst light-staved astrophotographers like a super-fast wide angle such as a 14mm F2.

Of course, you can use zoom. But if you know what you like to photograph and you are able to set your own distance, a fast prime might give you better results for less.

Fast Prime lenses for beginners

In many ways, a fast prime lens is optimal for beginners. When I first began using DSLRs, I only used the kit lenses that came with them. Although I was aware that prime lenses were much sharper, I was reluctant to invest in one since I thought I’d miss the versatility of a zoom.

Finally, I bought my first prime lens, a Nikon AF-S DX 35mm F1.8G, and I was blown away. Although I knew the image quality would be better, I was surprised by how much better it was.

But I was more surprised by how much I enjoyed the fixed perspective as it forced me to think more about composition and angles. As a result, I found the experience more engaging and began producing photos that looked different from the mainstream. In retrospect, the constraint of a fixed focal length might be the best thing that ever happened to my photography.

In the end, my kit lens went into a draw never to come out. Even today, my main lens is a cheap Nikon AF-S 50mm F1.8 and I’m able to work it into 90% of my photography. I even take it on professional portrait shoots because it’s so unintrusive and so damn good.

Of course, I still use zooms. For example, I like zooms for landscape photography since the scene is out of my control. And, I love a good 70-200mm for chasing down moving subjects.

Best fast prime lens for a beginner

The best place to start is a nifty-fifty. These 50mm primes (or equivalent) are practical, affordable, and super sharp and a low risk-way to find out whether fast primes are for you.

If you are a Nikon shooter, I can personally recommend the Nikon AF-S DX 35mm F1.8G for your D3500, D5600, etc as it’s super sharp, small, and compact. For full-frame, I still use and love my AF-S 50mm F1.8G as it’s a US$200 lens you can use on a professional shoot.

If you are looking for your first fast prime lens for a different camera system – check out this list.

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Fast Primes are lenses with a fixed focal length/perspective and a large fast aperture. They come in all sizes and there’s one to suit any budget. In comparison to an equivalent zoom, a fast prime will feature a larger aperture, superior image quality, and a smaller and lighter body. It’s also likely to be more affordable.

Of course, the downside of a fast prime is its fixed focal length. But if you shoot portraits, macro, or any other kind of photography where you can control the distance between you and your subject, a prime lens could be a superior option.

Fast Primes Improve your photography

In fact, a fixed focal length can be a relief. Without the temptation to simply zoom into an ideal composition, you are forced to get creative, find new angles and compositions. As a result, you’ll stretch photography muscles you never knew you had.

And it’s for this reason I recommend fast primes to beginners. But beyond developing your skills, a cheap fast prime such as a 50mm will finally give your camera’s sensor the image quality your kit lens never could. This includes a sharper image, better contrast, and vastly superior background blur.

Of course, sometimes you need a zoom. If you like to photograph birds in flight, your ideal focal length is dictated by the bird. But you might be surprised how often you can go without. For ten years, I have used a 50mm as my everyday lens whilst my heavy zooms sit at home awaiting their special occasion.

If you are thinking about buying your first fast prime lens, a nifty-fifty (or equivalent) is a great place to start as they are affordable, practical, and so, so sharp. If you’re unsure which is the best affordable fast prime lens for your camera system, I’ve listed them all here. Happy shooting.

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