advantages of fixed lenses

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hello, as a brand new amateur photographer I am full of questions. Here's the one for today: What are the advantages of having a fixed lense (i.e. 50mm) rather than a zoom lense which would include in it's range the same size? (i.e. 28-80mm)

thanks Josh J

-- Josh (hieronim@gmx.co.uk), March 04, 2002

Answers

http://cybaea.com/photo/lens-quality.html has a good comparison of a cheap zoom lens to a fixed focal length lens under "effect of lens quality." The site doesn't have the exact lenses you're referring to but you get the point. The 50mm will require less than 1/4 as much light, be much sharper, less distortion, and the out-of-focus areas will look better. Professional (L) lenses are much higher quality an a consumer 28-80 but also much more expensive and heavier.

-- Steven Fisher (steven_fisher@hotmail.com), March 04, 2002.

To amplify one of the points above, the prime (fixed focal length) lens will likely peform much better wide open--at its widest aperture. This allows you to shoot in low light and to take portraits in which the background is rendered very blurry (pleasingly so).

Photographers generally become very religious about their type of lens--and what it enables you to do and not do. I shot with zooms for a while and found that they made me very lazy and indecisive: "Should I go for the extreme close-up? Should I pan back?"

I found that shooting with the 50 mm forced me to become very disciplined, and it enabled me to develop a sense of what the photograph would look like before I snapped it. Now when I "zoom" I just walk forward, which means I am far more committed to the image than I would be if I had just rotated the lens barrel from the safety of a great distance. My shots are much better than before.

-- Preston Merchant (merchant@speakeasy.org), March 04, 2002.


Expanding on above....

Not only will the lens likely perform better at its wider apertures, but the lens will open up to a much bigger aperture.

For example, the slowest Canon 50mm fixed lens is an F1.8. My 24-85 is F4 at 50mm. Thus the fixed 50mm is 2.5 stops faster than my zoom.

Another advantage is that typically prime lenses have fewer elements in them, thus are less prone to flare than zooms. Distortion is much better controlled also, as the lens elements can be corrected for a single specific focal length, rather than having to compromise for a wide range.

-- Isaac Sibson (isibson@hotmail.com), March 04, 2002.


To add one point,fixed focal length lenses makes the use of P-L filter more convenient because the lens elements just move to and fro in focusing instead of the annoying rotation of zoom.

-- legnum (legnum212@email.com), March 05, 2002.

I feel it is important for a new photographer to have both. All of the previous reponses are true, in addition you should use the 50mm exclusively at first to get use to its characteristics, some of the worlds greatest photos were taken with 50mm lenses of much lower quality than todays can deliver. Starting out with this lens you will eventually discover the downside to an inexpensive zoom like the 28- 80.

-- joe cap (joemocap@yahoo.com), March 06, 2002.


I find that my needs in a lens are, in this order: 1) Small size and light weight. 2) Fast maximum aperture (for low light and easy focusing). 3) High image quality. 4) Different focal lengths. For my situation, the ability to zoom comes at the expense of other things that I find a greater need for, so primes are more desireable for me. Your situation may be different. For me, the position of the camera relative to other elements of the picture makes or breaks it far more than a change in focal length. I use one 50mm lens and a 35mm lens. That's it. There are lots of reasons to own other tools, but they don't apply to the kind of photography I like to do.

-- Bruce (bruce@aol.com), March 09, 2002.

I like fixed lenses but sometimes zooms are indespensible. I recently had an F100 system with 6 fixed lenses, but I was going crazy carrying and switching them all the time. So, when I went back to a 1v I decided to consolodate certain focal lengths into a couple of zooms. So now I am using a 28-70 f/2.8L, and have a 17-35 f/2.8L on order, which I augment with an 85 f/1.2L and (as soon as my dealer can find me one) a 135 f/2L.

BTW, the word "lens" does not have an "e" at the end.

Peter Hughes Photography

-- Peter Hughes (ravenart@pacbell.net), March 10, 2002.


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