fixed vs. variable lenses

newton · Joined: 10 Mar 2011 Posts: 343 Location: USA

I have a very basic question about why people choose fixed lenses vs. variable lenses. Beyond the obvious, I would like to know why choose fixed lenses at all when a nice variable lens can cover those fixed focal lengths? Are there specific photographic advantages to fixed lenses? I should know this but I don't and do not really understand. I seem to have taken decent photos with variable lenses and now am starting to take more photos with fixed lenses and am feeling the pinch, especially on the road. For studio work, the primes are quite nice, especially for IQ: bokeh, color, resolution, contrast, DOF, CA/PF, low lighting, noise, .... I read the discussion on flickr and a few other forums and was not satisfied, plus some of those forums degenerate into mindless quibbles and fights. I think a good variable fast lens may overlap with a few decent-to-good primes and am simply wondering what the thoughts are by people on this forum, who seem so much sharper and knowledgeable, btw. Wink

. If it is too basic a question, you will have to pardon me but I always like to revisit the basics in light of technical advantages today and practicality, like on the road, etc... When I was in Switzerland, this guy must have pulled out like ten different primes when I was carrying two zooms and one prime. I think I walked away with the better shots because he showed a grimace on his face as he was struggling to pick primes and after he shot each frame...

luisalegria · Expire: 2018-01-18

Some of us, like me, are just primitive and cannot learn to use a zoom !

Whenever I use a zoom I almost always just use it at maximum fl.

Seriously, there are several points here -

1. Zooming is not such a big deal if one sees a picture in a given fl. One step forward or backward fixes framing. Thats easier than being distracted by another control on the lens.

2. For fast moving photography there is little time to worry about framing with the zoom.

3. Primes generally have a larger effective aperture. So smaller DOF and the bokeh.

4. Zooms don't really cover all requirements for fl. An all-around zoom lens would be something like a 28-200mm. This class of extreme zoom lens has many image quality compromises. And what if what you really want is 20-200 ? or 28-400 ? There is no such lens. You will need, practically. a 20, a 50 (for bokeh, etc.) and an 80-200 zoom - and if you have an 80-200 zoom, you really can do just as well with just a 105 or 135 prime (one step backwards or forwards), which is going to be smaller with a bigger aperture anyway. The best use I see for 80-200 zooms personally is close focus.

rick_oleson · Posted: Thu Apr 07, 2011 2:55 am Post subject:

smaller (always)
lighter (usually, unless the zoom is plastic)
faster (almost always)
sharper (sometimes)
less distortion (almost always)

not everyone considers all of these things to be virtues - but some people do.

RioRico · Posted: Thu Apr 07, 2011 2:57 am Post subject:

My stock reply is: Use zooms to TAKE pictures, use primes to MAKE pictures.

Focal-length coverage isn't everything. I have ~200 lenses. A very few are zooms. I could 'cover' vast focal ranges on my Pentax K20D with just the DA10-17 fisheye, Tamron 10-24 ultrawide, DA18-250 walkaround, and Lil'Bigma 170-500 behemoth. But those are all fairly slow, and are all corrected extensively. They give a fairly same flavor to subjects.

My usual carry-around kit usually has some faster lenses: Zenitar 16/2.8, Vivitar-Kiron 24/2, Nikkor 35/2, FA50/1.4, Nikkor 85/2, Takumar-B 135/2.5. These all allow shooting faster-moving subjects and/or in lower light and/or with thinner DOF, than any of my zooms.

I'll also carry some slower lenses: Lentar-Tokina 21/3.8, Meyer Helioplan 40/4.5, Macro-Takumar 50/4, Schneider Betavaron 50-125 enlarger zoom, Enna Tele-Sandmar 100/4.5, Tele-Takumar 200/5.6. Some are small, most are idiosyncratic, all have 'character'.

And I also carry a small bellows and various cheap enlarger (EL) and projector lenses, because the EL's are damn sharp, and the projector lenses have interesting character. And it's really fun to work with lenses that I can focus from a few inches to infinity.

'Coverage' means you can take shots of many subjects in good light without having to move around much. Zooms can be good general-purpose tools. But you can also look at what's around you with the singular eye of a singular lens. Back in the day, a shooter might carry just 3 lenses, a wide, a normal, and a tele. You get to decide: What sort of shots do I think I'll take now? And that's a good exercise now. Pick a prime. Shoot with ONLY that prime for a day, a week, a month. Then pick another one. You learn to look at the world as seen with that lens, and how to work with it.

Again, many primes are much faster than most zooms. And many older design primes have certain special properties, what we call 'character', which may involve bokeh, dimensionality, rendering, sharpness (or lack thereof), whatever. Some give very distinct flavors to images.

Think of painting. It's possible to paint with just a single brush. But that's a rather crude way to approach a canvas or wall or whatever. Each lens is a different tool, a different brush, that can do different things. Much of the fun is in comparing those difference, and learning to use them.

To record what's around you, an advanced superzoom P&S may be just fine. To *interpret* what you see, a boxful of primes may be a good start.

poilu · Expire: 2019-08-29

cooltouch · Joined: 15 Jan 2009 Posts: 9098 Location: Houston, Texas

Paragraph breaks have always been something of a judgment call, poilu. I for one can follow what newton is writing about with little difficulty. Now, if he didn't use periods or question marks, that would be another thing, entirely.

But back to the topic:

Even though I prefer to use primes whenever possible, I answered this debate to my satisfaction a long time ago. If I'm traveling light and it just really isn't convenient or practical for me to drag around all my primes, I'll usually carry three lenses with me. I too have never been very fond of the one-zoom-size-fits-all idea because there's usually something important being sacrificed. Either the lens speed is too slow or there is too much distortion, or resolution/contrast suffers. It's typically a trade-off in one or more of these areas. So, I've always preferred dividing the zoom chores up between two zooms and I've found that this has worked well.

With film, I've had really good luck with carrying two zooms: a high-quality wide angle to short tele, such as the Vivitar S1 28-90 f/2.8-3.5, and a short tele to long tele, such as the Vivitar 70-210 f/3.5. I will also usually carry one fast optic, like a 50mm f/1.4.

When shooting digital, because my DSLR is an APS-C crop-body, I will carry two zooms also: an EF 18-55 zoom and either an EF zoom, like a 70-210 f/4 or an MF zoom, like my Tamron 60-300mm f/3.8-5.4 (which I also like carrying instead of the S1 70-210 with my film kit too). I will also usually carry one fast optic, like my 50mm f/1.4 Nikkor, but because my DSLR's focusing screen does not allow for accurate focusing at apertures faster than about f/4, I have to use live view with that lens unless I stop it down, which makes it not as useful for the narrow DoF and big bokeh, which is a big reason for carrying it around in the first place.

I have witnessed many occasion when prime-obsessed photographers were spending time rummaging around in their camera bags for just that right optic, while I was busy grabbing all the good shots that they were missing with my allegedly inferior zooms. To paraphrase somebody important in photography, the best photos are the ones you actually take.

Finally, I gotta disagree with Luis's point #2. I have found that, with very fast moving subjects, sometimes the only way to frame them precisely is by using a zoom. One can only run toward or away from a subject so fast. And if one can't run toward or away from a subject that is moving toward or away from the photographer, then what? It is the ability to rapidly change framing of a subject that is one of the most appealing aspects of zoom photography. Or so I will argue.

Orio · Expire: 2012-12-04

newton,
better to speak of fixed vs. variable focal lenght, it's clearer. Usually people refers as "fixed lens" to those lenses that are permanently attached to a camera body.
Having that said, there is a simple reason why demanding photographers prefer fixed FLs: the image quality they give is, on average, visibly superior. There are some zoom lenses that do rival the quality of the primes; some Leica and Zeiss zooms do perform as or sometimes even a bit better than the corresponding primes. Most zooms however perform worse, in one, some or all of the following aspects:

- image definition (clarity)
- distortion
- vignetting
- chromatic aberrations
- spherical aberrations (like coma)
- speed
- weight
- bulk

Zooms have this (in my opinion limited) advantage that they don't force you to change lens so often (but still they do require you to change optic sometimes, unless you want to use one of those 18-200 zooms that are total optical crap). But this advantage is more teorical than practical. For photos that you can compose, like landscapes, you have time to make your choices; for photos that you need to snap, no zoom can beat the quickness of a medium FL prime, 28, 35 or 50mm, set to hyperfocal.
_

BRunner · Joined: 29 Jul 2009 Posts: 705 Location: Czech Republic

When I want perfect quality, or I have time, or I just want to have fun, I prefer primes. But when I'm doing some "reportage" style photography, I always choose zoom and when possible, I carry two bodies one with 28-70 zoom and one body with 70-200. Most of the time, you don't have time to switch the zooms on one body...not to mention searching for right prime in bag...

AhamB · Joined: 22 Jun 2008 Posts: 733 Location: Germany

RioRico · Posted: Thu Apr 07, 2011 3:31 pm Post subject:

Another metaphor: A lens is a window on the world. Wide-focal-range zooms give a very expansive view; narrow zooms, have a more restrictive view; primes, each give a very specific view. These are appropriate in different situations. Zooms are great for dynamic, changing scenarios; primes are great for more static scenes, or where you want to concentrate on one FOV (field of view). A zoom is a multi-tool; a prime is a precision scalpel.

Don't fumble for primes when stuff is happening around you. Maybe carry two cameras, the prime-of-the-day on one, a general-purpose zoom on the other. Or use the prime-of-the-day to challenge yourself to move to where the action is. Sometimes I've had to cover events with just one fixed-lens camera. I learned agility, yes I did. I think it was Robert Capra who said, "If your picture isn't good enough, you're not close enough."

I can wander through San Francisco's old Chinatown with various lenses. The 10-24 is great for street scenes and shop interiors. The 18-250 is good from street scenes to specific details, a good 'reporting' lens. But what I *prefer* are a slow, tiny 100/4.5 for bright days, and a fast 85/2 for murk and dusk. These force me to see and compose carefully. Or to pull-in a cramped space, I like my fishy 16/2.8, and go with the slight distortion. So my only lens-fumbling comes when I want to change FOV.

fuzzywuzzy · Expire: 2013-11-30

Some of us are poor/stingy and like the bang for buck we get from vintage primes Smile

ZoneV · Expire: 2011-12-02

I started photography with zoom lenses.
But for faster lenses I bought fixed focal lenses. And now some 20 years later I prefer to work ~95% with primes.

Why?

I like fast lenses - and use them very often wideopen - 58/1.2 85/1.2 and 1.4 and such. Even my 14/2.8 I like to use @ 2.8. I like the short DOF, I like the very blurred background, I even use the f/1.2 lenses for macro work wide open.

But there are additional reasons: I like the most times better build quality of prime lenses, because they are better to convert and to repair.
And I like old lenses, and more old zoomlenses are much worse than their prime counterparts.

On rare occasions I am to slow to get the right lens for the right moment, but I don�t like to take pictures fast. I want enough time to observe the object I want to photograph, I don�t like to "hunt" the object.

Regarding the kind of writing without paragraphs:
I don�t like that - but I could freely decide if I want to read and answer - or not.
I am happy to read much in more or less correct English - helps me to learn the language a bit better.
I suppose that some will not like to read and answer some of my bad English language posts too - no problem with that.

In Germany the problem is much worse: We use capitals very often, all nouns are written with capitals. But some don�t do that on the internet. Doesn�t like that too.

RioRico · Posted: Thu Apr 07, 2011 4:29 pm Post subject:

ylyad · Expire: 2013-12-05

After the usual kit zoom, I started to go towards prime, mainly because of cost for speed, with a 50/1.8 and I really enjoyed the discipline of making photos with a prime
A I wanted to expand, the only real cheap way was M42 and the first advice was: primes are good to exceptional, zooms suck (since then, I've discovered here that it's not true Wink

but it was OK to me, so I continued with primes)

Now, I still like my primes and I don't miss a zoom. But on wide/ultra-wide angles, I'm not satisfied with what I have, and that's the area where old MF primes are rare and expensive anyway, and not much faster than good zooms... OK, there are differences, but the alternative is much more questionable.

cooltouch · Joined: 15 Jan 2009 Posts: 9098 Location: Houston, Texas

Attila · Expire: 2025-11-18

newton · Joined: 10 Mar 2011 Posts: 343 Location: USA

I feel like I was doing okay without all my new (old) primes. I do notice one big thing though that is pretty obvious: this absolute beauty in bokeh, color, resolution/sharpness, CA and vignetting. My pictures look more realistic with my (new) old primes...and they have that old fashioned 60's and 70's look that I adore. I was using these older primes on my analog bodies for a long time and felt discomfort when all the locals were screaming about digital photography and how it was so great, while my eyes and my heart were telling me that my primes on my old analog slr's were superior, in terms of the images they captured. I can only say that I am glad that people on this forum agree; it is not that way in the real world, aka, the digital community I live in, stacked with new (young) (novice) naive? photogs (wannabeeees?). I am glad people here like the older lenses and primes; it is simply obvious.

Regarding my writing style, ummm.....I will have you know that I won a book award and a few other prizes for my writing, but I like to hear that it sucks because it only makes me want to learn and do better, both stylistically and format-wise. Sorry for the long paragraphs. It could be a result of the forum not parsing the text in a smoother way or a result of the font being so small and dense. I used to hate reading, but now I love it and don't mind gleaning from text no matter how dense or stacked it is. It now feels good to see and read lots of words, so I guess this is how I write now......but I can change

it

if

you

would

like. Smile

(Just being facetious......I will do better....I promise)

--
One note or question? Why is everyone saying that the older zoom lenses are inferior?

RioRico · Posted: Fri Apr 08, 2011 5:43 am Post subject:

@Newton,
I think you'll find that creative writing styles are not necessarily best for imparting information. I speak as a published poet / songwriter, essayist, propagandist, programmer, journalist, and technical writer. Obscurantism has its place. But clarity is better rewarded -- with attention, if not wealth. There is a tendency when writing software to produce WRITE-ONLY CODE, stuff that's impossible for humans to understand. I try to avoid that now.

As for old-vs-new zooms: Technology has improved dramatically in the last couple decades. New materials, better software, etc. Zooms of the 1960's-70's-80's pushed the then-current limits of glass and mainframes. But whereas many primes can still use old hand-calculated optical formulae, modern zooms are extraordinarily complex beasts -- their numbers crunched on supercomputers, their optics molded of exotic materials, all watched over by machines of loving grace. (R.Brautigan)

Some few older zooms are quite good, even legendary. Most have been supplanted. Not all, but enough. We can expect that except for a few premium lines and notable outliers, *most* newer zooms are optically better than *most* older zooms.

newton · Joined: 10 Mar 2011 Posts: 343 Location: USA

RioRico,

By that logic, why shouldn't newer primes be better than older primes?

martinsmith99 · Expire: 2013-11-18

A lot of lengthy answers here, but I use a zoom when I know I will need lots of different focal lengths; a prime or primes when I only need 1 or 2.

The arguement with IQ doesn't really hold up with modern zooms, although it will apply to DOF & speed.

ylyad · Expire: 2013-12-05

Pancolart · Expire: 2013-11-18

Interesting topic. One analogy comes into my mind. Some people like complex food with many ingredients. Some even mix everything together all that is brought to their plate before eating. Others like simple food of basic tastes.

You can imagine manipulation that is forced upon light if it goes through 3-7 glass elements (primes) compared to fuzziness of more then 10 elements (zoom).

AhamB · Joined: 22 Jun 2008 Posts: 733 Location: Germany

Agreed with what ylyad says. Only quite recently we see some new primes with quite big jumps in IQ from Canon (2nd version of 24/1.4, 24/3.5 TS-E, new TS-E 17/4) and Nikon (new 24/1.4 and 35/1.4).

RioRico · Posted: Fri Apr 08, 2011 2:25 pm Post subject:

visualopsins · Expire: 2025-04-11

Modern zoom lenses are faster, some have better IQ than older zoom lenses. The first zooms had limited focal range, there were no lenses than made the transition from wide angle through normal to telephoto angles of view, because the design mathematics are too tedious for hand calculation -- instead of a computer, designers would hand off the calculations to rooms full of people to make. Computers made the tedium of calculations manageable, zoom designs that cross over the normal view range appeared, such as 28-105 and 28-135 designs. These designs have been refined, new materials have permitted faster lens designs, for both 'crossover' zooms and the older limited-range zooms.

In my experience some older zoom lenses have good IQ, but they are not fast lenses. Those with limited telephoto zoom range, those that do not cross the 'normal' angle, such as 70-210mm, are better than the early versions of 28-105mm and 28-135mm, and better than early wide-angle zooms, such as 18-35mm.