Hi,
Zoom lens i can zoom from a certain mm to another mm n with certain F number.
Fix lens is fix i cant zoom.
Isnt zoom lens better n cheaper :bigeyes:
Rgds,
Here are some reasons why people buy prime lenses :
Price . Primes by virtue of their simpler construct are generally cheaper , and good value for money considering their outstanding image qualities. Of course there are some very expensive primes with very large aperture.
Small and light. Compare a tiny 45mm f2.8P with a monster 28-70mmf2.8. While there are comparable fast f2.8 zooms, they are usually bigger in construct and less stealthier for street shooting, and also pricier ( along with the larger diameters that they take ). A 70-200mm VR is more likely to wear you out compared to an 85mm prime for a holiday.
Larger aperture. Some of the primes offer a bigger aperture than what the current zooms can offer. For example the 28mm f1.4, 50mm 1.4, 85mm f1.4, 105mm f2 ..
Better image quality. With a simpler construct, it is easier to control lens distortions compared to a zoom that has many more focal lengths to work on. While this is probably true for the cheaper zoom lens, the newer high end zoom lenses are pretty much on par if not better than the older prime lenses. The nikon 14-24mm f2.8 is regarded to have superior optics compared to the old AF 14mm f2.8 prime. Less lens elements also means there are less surfaces to have internal reflections contributing to unwanted flares.
Good starting point for learning. Many people believe that people new to the hobby should try work with prime to appreciate concepts of focal length and perspectives. this is .. subjective. Nowadays the kit lens packaged with a camera for sale is no longer a good old 50mm prime but rather a zoom.
Shorter working distance. This is not exclusive sweeping statement. But in general a prime lens can provide closer focusing distance compared to a zoom. This may or may not be your consideration in making a decision depending on your shooting needs.
Why choose zoom ?
Image quality. Because the current zoom lenses are so well made. The Nikkor 2.8 zooms are pretty much on par with the prime lenses and some of them outshine the performance of older prime lens because of additional special coatings and ED elements on top of improved designs. For example the AFS 14-24mm/2.8 performs better than the older AF 14mm/2.8. The old comment of zoom lenses taking inferior quality images is now an unfair statement to make, and I would ignore any nit picking comparisons when I purchase a good zoom lens. The more consumer range variable aperture zoom lenses while not optically as good as their constant aperture 2.8 pro zoom cousins, provide good quality for all users as well. The 18-200mm VR is a versatile variable aperture zoom that I often bring along for holidays.
Convenience. The obvious, and they are so many reasons. You want a lens that covers abit more range because your subjects are unpredictable. You want a hyperzoom for flexibility when you are on holiday to catch moments without the need to change lens. After all it is always better to nab a great picture with an average quality zoom than to lose capturing that great moment at all. A fast moving subject will force you to pre empt the framing when the subject is about to enter your composition, but if you miss it, the zoom will give you a second chance at it, and this is especially so when you are overly particular at balancing your bckground, subject cpmposition. Your 50mm might be abit wide at a particular shot and necessitate subsequent cropping. The zoom will let you have the right focal length without crop.
Weight. While a 28mm is certainly lighter than a 24-70mmf2.8 zoom, but the zoom is lighter than a set of 24mm, 28mm, 35mm, 50mm, 60mm prime lenses.
Depth of field scale. Most of the primes will still give you a trusty DOF scale that relects the estimated extent of the DOF you can cover at a corresponding aperture. This is usually not found on zoom lenses, and calculation is complicated.
The reasons are not exhaustive for either.
At least for me, there is no right or wrong in choosing either. You can take great shots with your consumer zoom or you can bring just one 35mm lens and take great 35mm shots. It is getting the right tool for ur kind of job.
Ryan