It is not a measurement of the actual length of a lens, but a calculation of an optical distance from the point where light rays converge to form a sharp image of an object to the digital sensor or 35mm film at the focal plane in the camera. Please fix this. Lenses with the fewest number of moving parts (i.e., internal focus and internal zoom) are generally ideal, since it allows for fewer points of failure. Brand name, lens type, focal length (in mm), maximum aperture, other lens features/abbreviations.For example, the official name for one of Nikon’s professional zooms is the “Nikon AF-S 24-70mm f/2.8 E ED VR” lens. Some are better, some are worse. (At focal lengths in between, your maximum aperture gradually changes from f/3.5 to f/5.6.). There are dozens of image quality factors that make some lenses better than others. Selecting a new camera lens requires time and research because you have to consider several factors; desired focal length, lens speed, compatibility with your camera… A few specialty lenses on the market fit somewhere between primes and zooms, such as the Leica 16-18-21mm f/4 lens. If you have any questions or comments, feel free to let me know below and I will try to get back to you! Some lenses have better bokeh than others. This lens covers three specific focal lengths – 16mm, 18mm, and 21mm – but none of the focal lengths in between. Not all lenses have autofocus, and not all autofocus lenses are equally fast and accurate. Spencer great article, wish I had the information you provided when I started buying lenses, I can think of several that would not have made the grade. Are these ever worthwhile choices? What about the abbreviations at the end of the lens name? The other critical term in a lens name is the “f/number” term, which stands for the lens’s maximum aperture. In truth, this is usually more a function of sample variation AND people not taping into the camera’s capacity to address these issues – AF Fine Tuning. Right or wrong, the top feature on everyone’s mind when a new lens comes out is sharpness. The lens is what focuses light from what you see through the viewfinder into a tiny, (typically) 35mm spot on the back of your film, DSLR, or mirrorless camera. I don’t care about small differences, but a bad lens here will not end up in my bag. If one in ten copies of a lens is bad, most reviewers will never notice, but a high percentage of users will. Most of the time, the user has failed to evaluate the combo and make the correct AF Fine Tune adjustment. So, don’t avoid variable aperture zooms by default. The three main types of distortion are pincushion, barrel, and mustache. You can calculate the exact amount simply by multiplying your lens focal length by your crop factor. Is it worth saving that money, or are you paying for third-party lenses another way – through their lack of quality? Most will just conclude the teleconverter is “a bad one”. Our ad network periodically gets “bad advertisers” who sneak in ads like that. Your camera lens’ maximum aperture number, measured in “f-numbers” or “f-stops,” is usually indicated in the same manner on every lens. It’s especially visible if you use a wide angle lens, since you need to get much closer to your subjects than with a telephoto: This is why most portrait photographers prefer an 85mm lens rather than a 24mm lens for headshots. Zooms usually max out at f/2.8, while plenty of primes on the market go to f/1.4 and sometimes wider. In this 9 part video series, you'll learn about lens basics and the various lenses available. There are tons of other lens features that matter in photography. Lens Basics. This really gets messy when one starts using teleconverters. Personally, my primary concern with sharpness for landscape photography is that the lens remains sharp in the corners at f/8 to f/11, my most common aperture range. For example, if a 10X optical zoom lens on a digital camera has a minimum focal length of 35mm, the camera would have a 350mm maximum focal length. Do they work on the assumption that many of us might not notice and if we do, that is why they provide a warranty? Performance & security by Cloudflare, Please complete the security check to access. (Milky Way photography is one exception. You may need to download version 2.0 now from the Chrome Web Store. Just like the pupil in our eyes, the aperture in a lens will let in more or less light. Some photographers may consider 35mm to be wide angle rather than normal, or vice versa, and it’s not a big deal either way. It would be very frustrating to read a good review of a lens online and find that yours isn’t nearly as impressive. This is called minimum aperture. Alongside lenses made by camera manufacturers like Nikon, Canon, Sony, and so on, countless third-party companies make lenses, too. My favorite wide angle zoom is a Tamron lens (the 15-30mm f/2.8), and my sharpest lens is a Sigma (the 50mm f/1.4 A). There are some bad third-party lenses floating around, just like there are some bad name-brand lenses. (I’ve got a full section later on each one and why it is so important.). Lenses. However, if the digital camera offers … In that case, the third party lens is usually (though not always) less expensive. Each part of the lens serves an important purpose: Not every lens has all seven of these features, and other lenses have many more than this. Personally I’ve been free from those ads for several months, for whatever reason.