mikegreenwald Loc: Illinois

My reference will be lenses for interchangeable lens cameras only.
I have experience with Canon ILC equipment only. Feel free however, to comment on Nikon, Sony, aftermarket and other OEMs as well.
Zoom lenses have become excellent in terms of IQ in the last couple of decades. With the shorter ratio zooms, certainly down to 3:1, possibly 4:1, most images are useable even up to very large prints. Certainly low light impacts IQ. The extremes of range, sometimes at one end, sometimes at the other, often at both ends, IQ is mildly impacted. At zoom ranges greater than 4:1 I have not been happy with IQ.
What is your experience?

larryepage Loc: North Texas area

I had a detailed reply put together, but accidentally wiped it out by hitting the "Back" button on my phone. Here's a quick summary of what it said.

I have a mix of relatively modern Nikkor fixed focal length and zoom lenses. Except for an older 18-200mm DX zoom (11:1) which has failed, all are less than 5:1.

The 18-200 lens was used for a couple of very specific situations. It always did OK, despite being a "flaky" lens in several respects. With one exception, all of the other zooms have done a fine job for me. The exception was a first-generation 18-70mm Nikkor DX (4:1) from about 2006 that was just an unacceptably poor lens. It was never sharp, and it was sometimes inconsistent from one area of the frame to another. I've since given it away.

I believe it is true that zooms which include both wide angle and telephoto focal lengths with only a single zoom motion generally perform less well than those for which two sets of zoom motions are visible...one on the wide-angle side and a different one on the telephoto side. This is easily visible in the Nikkor 24-70mm f/2.8 (3:1).

Having said all this, except for the 18-70mm DX lens, honest assessment of any unsharp images tracked back to me, not a particular lens. And I use cameras with high sensor densities. If we're really honest, I suspect that the same is true of unsharp images posted here...something that the photographer either did or did not do.

I photograph railroads and industrial installations and other subject matter where I do not get to choose my vantage point for shooting. And i have a number of nice fixed-length lenses that cover from 35-300mm. They are mostly not entry-level lenses. They don't get used very often. The flexibility of the zooms, which cover 14-500mm, trumps any real or imagined extra sharpness.

Tomfl101 Loc: Mount Airy, MD

My 24-105 L Canon lens produces very sharp images at all focal lengths. Unless I need the speed of a fixed focal length I find little IQ decrease with the zoom. Same with my 70-200 2.8.

jjanovy Loc: Lincoln, Nebraska

From an artistic perspective, I find the flexibility of zoom lenses to be the overriding positive aspect.

ELNikkor

My friend who has the 18-300 Nikon DX lens on his D7500 gets very sharp images at all focal lengths. For some amazingly sharp photos taken with wide-range zooms, check Ken Rockwell's site.

billnikon Loc: Pennsylvania/Ohio/Florida/Maui/Oregon/Vermont

Generally speaking is your not getting sharp images with todays zooms you better check your shooting techniques.

yssirk123 Loc: New Jersey

The Nikon Z 24-200 zoom is an incredibly versatile lens with excellent sharpness in the center and good to very good sharpness in the corners. I've had no problems making very large prints that can easily withstand close scrutiny.

Jimmy T Loc: Virginia

All of my Canon camera lens are “L” glass.
I find that my 24-70 f2.8, RF 24-105, RF 28-70 F2, and my RF 100-500 don’t limit me in any way. Modern optics are a marvel. I am the weak link.
Best Wishes,
Jimmy T Sends

wmurnahan Loc: Bloomington IN

My Sony 200-600 is sharp as a tack as is my 70-300. Zoom lenses have come a long way since I got into photography in the 70's.

camerapapi Loc: Miami, Fl.

We all know that zoom lenses have compromises. As has already been stated modern zooms have excellent quality and it is not unusual to see professionals using them.
Nobody here will deny that a zoom is a convenient lens. The fact that we can change focal lengths could make the difference between getting or losing a shot. Zooms have complex optical formulas and as I said, they have compromises but in general and based only in my experience the results in general and using good techniques are excellent.

I own two well known Nikon zooms, the 18-70 and the 18-200 VR. The AF function of the 18-70 failed and I have been using the lens in the manual mode. In my opinion the lens is an excellent performer. I have seen many reports online that recommend to keep away from the 18-200 VR because of its poor performance. If indeed there is a variation of samples I must have a good one. The 18-200 is f3.5 at the wide end while it is f5.6 when it is near its tele side. I usually shoot it at f8 or above and I have been very satisfied with my images from it. I seldom go beyond 12x18 inches with my enlargements but in the computer I crop to 100% and the details, if I used good photographic technique are there.

Larger ratios like the 70-300 VR and the 80-400 VR, in my case both are older versions, have also been excellent performers. Understand that using those zooms require even better photographic techniques. I usually use them on a tripod with high enough shutter speeds to make sure I minimise motion.
When I have used them handheld with at least an ISO 400 and under good lighting the results have also been excellent. None of these zooms excel in low light, for that a zoom with a fixed aperture like f2.8 is much more practical.

I have fixed focal length lenses but a zoom is so convenient that using a fixed focal lens for me is kind of unusual.

olemikey Loc: 6 mile creek, Spacecoast Florida

ELNikkor

Yes

Canisdirus

All modern zoom lenses...that cost serious coin (the relationship usually holds)...are sharp.

They won't touch primes...but they are better than they used to be.

Every convenience in life...bears a cost.

whatdat Loc: Del Valle, Tx.

I use the same camera & lense combo. I am totally pleased with the results.

olemikey Loc: 6 mile creek, Spacecoast Florida

I also use this lens with D71/7200 series (often).....no complaints at all.