Comparing Zoom Lens
Study and Compare Lenses Carefully, go for Quality!
Hopefully we can help by doing most of the donkey work for you whether you are comparing zoom lens makes, models, manufacturers, features or prices!
Why do I sometimes prefer a zoom lens as opposed to a "Prime" lens?
If it is a matter of quality, I prefer the fixed focal length lenses. However, for the convenience and "less to carry", I would rather use quality zoom lenses.
Although the prime lens, if of a certain quality, will normally give superior shots, there is so much you can do with a zoom lens. For example, if you are tracking wildlife or sports subjects, it is incredibly handy to keep re-framing as you are shooting. For this example I had to drag myself to the beach and watch the moto x event all day. So I hope you appreciate it ; )
Check out the GIF animation above of a competitor.
To illustrate what I mean, this series of pictures was quickly taken using the Canon EOS 5D Mark IV at 7 FPS (frames per second).
I also used the Canon EF 70-200mm F2.8 L lens.
It is to show how you can track a moving object while keeping it in the frame using a zoom lens.
Imaging you are photographing at a Grand Prix event (lucky you!), and the car is coming towards you. If you were simply using a fixed telephoto lens, it wouldn't be long before you were just photographing the bumper as the car got nearer.
The beauty of a zoom lens is that you have that flexibility. The ever-so-very-slight loss in quality is more than made up for by its usefulness in my opinion!
Comparing zoom lens: Types
Ok, you want to buy a zoom lens. Just like any other aspect of photography, think about what you want it for. Don't just buy an expensive 16-35mm lens because your friends have one. It will be a costly "keep up with the Jones's".
Are you building a set of zoom lenses that will get you from say, 16mm to 200mm? that way, you will cover all angles at wedding or portrait photography. The lenses I would recommend would be maybe;
The latter of the two is great you want to cover 100-500mm for sports or nature/wildlife photography.
Whatever you choose, I would say to try and stick with the same brand. It isn't that important, but you will become familiar with certain makes. That can help when switching from one to the other in a flash.
As I have said in other parts of this site, don't go for poor quality glass, you will regret it! If you can't afford new, buy second-hand. Lenses are easy to check for damage or dust. Just look through it and check that all the moving parts still operate smoothly.
It might even be worth buying a damaged lens and getting it repaired. I just had (in 2021) a Canon L 24-70 f2.8 lens repaired for £92. Well worth it in my opinion.
If the branded lenses such as Canon, Sony, Panasonic S-Series or Nikon are out of your budget, I will always recommend "Sigma" when comparing zoom lens manufacturers.
The quality of their products and the amount of research and development behind them, makes them a top competitor for the larger brands. Their lenses will fit most of the larger makes and models of SLR, digital or film.
Go to their website and have a browse, read forums and check the reviews from owners at Amazon.com.
Comparing zoom lens: Quality
This is important. Please check users reviews, forums or test them yourself before buying. Look for photographs taken by various lenses and listen to what more experienced photographers say.
I say that because I read a few reviews from beginners in the past that absolutely slated the Canon EOS 20D on release. Great camera and still is in 2021. It is more often than not, that they have bought too big a camera for their experience, and haven't learnt how to use it properly yet.
As much as I love them, Canon released many older DSLR's with the sh*tty EFS 18-55mm lens. Now, admittedly, for people on a tight budget, this lens will do until you can afford a better one. However, if you were looking at buying this separately, I wouldn't. Again, this is just my opinion.
The lens on the left is the Canon EF 50mm F1.4, on the right is the EFS 18-55mm.
The 50mm has a steel bayonet mount, whereas the EFS lens is plastic, which is also made in Taiwan. As opposed to Japan for the 50mm.
The focussing ring on the new EFS is virtually non-existent and fiddly for manual focussing. It feels light and "Cheap". I hate to say bad things about Canon, but try and buy the "body only" DSLR from them if you are considering it.
I only say all this because if you are getting serious or want to earn a living from photography, and if you buy cheap now, you will only replace it all later anyway. You are better off just getting one better quality zoom lens (like the Canon EF 24-70mm IS USM or slightly cheaper 24-105mm), instead of 2 or 3 cheap lenses.
So, when comparing zoom lens quality, this advice also applies to Nikon, Olympus, Minolta or whatever make of camera you have. A quality lens will always feel heavier, more sturdy, will operate smoothly and have better quality glass. The lens and your own imagination are what make a good photograph, the camera make or type is not so important.
Comparing zoom lens: Features
When you are comparing features, what are you looking for?
Most modern lenses have autofocus and work in conjunction with your camera. However, it is sometimes nice or necessary, to switch to manual focus (e.g. for macro work). Make sure the lens has this.
One touch or two touch zoom
There are 2 ways of altering the focal length when using a zoom lens. The more common is for the lens to have separate focussing and zooming rings. The other (such as on the Canon EF 100-400mm), is for the lens to incorporate the focussing and zoom functions on the same ring. This means you can focus and zoom at the same time as the zoom is on a push-pull basis. For the focussing you twist the barrel. It is purely personal preference as to which you choose.
This is a nice feature to have, especially for the longer zoom lenses. These lenses have a motor inside which detects your movement (when the shutter is partly depressed) and counterbalances it. It means you can hand-hold the camera for up to 2-6 extra stops (when used with sensor stabilisation) before you need a tripod. Again, personal preference here, the feature can sometimes be a hindrance but is mostly of benefit.
USM or HSM
Most of the larger manufacturers now put this into their better lenses. Ultrasonic or hypersonic movement means the lens has another motor which allows it to focus quickly and silently. If you are shooting weddings or anywhere quiet, this is an excellent feature. You just have to worry about the shutter noise ; )
Lastly, when comparing zoom lens features, check the speed or largest aperture of the lens. This should be F.4 or F.5.6. Any larger such as F.8, and you will struggle to get a reasonable shutter speed.
The highest quality lenses can keep F2.8 throughout the entire zoom range but, yes you guessed it, they cost a lot more. Most of the Canon "L" series lenses, Nikon VR series, Panasonic and Sony all have this feature. That is why they are so popular with press and sports photographers.