Part I review of the Sony 24-240mm on the Sony A7R is at http://photoblog.velgos.com/2015/03/sony-fe-24-240mm-lens-initial-quick-review-sel24240
Part II review with the 24-240mm on the Sony NEX-7 is at http://photoblog.velgos.com/2015/04/sony-fe-24-240mm-lens-review-part-ii-sel24240
Part III of the Sony FE 24-240mm F3.5-6.3 OSS Full-frame E-mount Telephoto Zoom Lens Review. In this review I wanted to see how the 24-240 stacked up against my Sony 35mm f/1.8 prime lens on the APS-C sensor Sony NEX-7.
Sony 24-240mm (SEL24240) vs Sony 35mm F/1.8 (SEL35F18) on a Sony NEX-7
After I posted my first review of the new Sony 24-240mm I checked out other reviews and reader comments. Some people were saying that the initial 24-240 tests were looking pretty good while others were saying it’s not good enough for them and they’ll stick with their fixed focal length prime lenses. As I read more zoom versus prime comments I began to wonder how much of a difference there would be between the 24-240 and a prime lens. The last time I compared my 18-200mm to a prime it actually didn’t do too bad. So I decided to check the 24-240 against my Sony 35mm f/1.8 which is known as a pretty sharp lens.
Comparing the image quality of a general purpose zoom lens against a fixed focal length prime lens is somewhat unfair. By default, a prime lens will almost always have better sharpness, less distortion, and much better optical performance in just about every way. But, a prime lens can’t zoom. And that’s the main tradeoff. With a zoom like a 24-240 you get decent optical quality with the convenience of not needing to change lenses. With prime lenses you get excellent optical quality but need to switch lenses if you want a different focal length.
So the question becomes, is the quality difference so much better with prime lenses that it’s worth the effort of changing lenses instead of using one zoom lens to cover a large focal range? It depends on a person’s needs. If you’re a studio portrait shooter you may mostly use something like an 85mm f/1.4 and on the rare occasion you need to switch lenses it only takes a few seconds. For a landscape photographer, changing a lens during bad weather conditions may not be an option and could mean missing that spectacular blue light shot.
So let’s take a look and see how the 24-240mm and 35mm compare at 35mm f/8 on the Sony NEX-7. While this doesn’t compare different focal lenths it should at least give a general idea of how the zoom does against the prime.