[BARCUD]

Hi guys, I'm just getting to grips with the different types of lens available to compliment my kit lens on my new K10D. I've been looking at lens such as the sigma 17-70 but my question concerns prime lens.

Can you get wide angle prime lenses ?

If you get a 50mm prime for example do you have to move towards the subject until it fills as much of the frame as you want ? Is a lot of cropping involved ? Isn't this very restrictive ?

BARCUD

[Mallee Boy]

Hi Barcud,
The theory is that prime lenses are of a higher quality and that zooms have to make comprises across the focal range by the nature of the complexity in the design. It is generally accepted that zooms will have some flaw somewhere in the range, usually at either end of the spectrum.

As to how to use a prime....try this:
Assuming you have say the kit lens on you camera now ie) 18-55, set it to say 50mm (your example) and just use it at that focal length for a day. Also have a look through your photos and see what is your most used focal length.

Zooms & primes are available across the entire focal length range (that is a generalisation), it is the price that is not general.
Cheers

[bwield]

- The sigma 17-70mm wouldnt really complement your 18-55, but instead replace it.
- Yes you can get wide angle primes. (da 14mm / da 21mm)

With primes you really "zoom" with your feet.
Some do find it restircting and thats probably why zooms are so popular, however I find that when using primes I think alot more about composition and really pefer it too zooms. I suppose there could be alot of cropping, but thats just subjective as you can do alot of cropping with zooms...
The best advice that I've heard is when considering primes and which focal lengths etc.. Use your zooms (18-55) and find out at what focal length most of your pictures are taken.. OR just set your lens at one length (ex. 35mm) and try going around without zooming in or out.
This will give you an idea what shooting with primes is like, as well as letting you see what focal lengths you pefer

(Malle Boy beat me too it lol)

[8540tomg]

Hi guys, I'm just getting to grips with the different types of lens available to compliment my kit lens on my new K10D. I've been looking at lens such as the sigma 17-70 but my question concerns prime lens.

Can you get wide angle prime lenses ?

If you get a 50mm prime for example do you have to move towards the subject until it fills as much of the frame as you want ? Is a lot of cropping involved ? Isn't this very restrictive ?

BARCUD

Barcud,

I'll preface this post by saying I prefer primes to zooms in almost every case. They will certainly be better than any kit lens. Yes, you will have to move more with a prime lens than a zoom. That being said, some argue the best zoom ever made was your two feet. You will find, however, that primes lenses are "almost" always optically superior to zooms at their designated focal length. As far as cropping goes in most cases just move closer to the subject. Once you get used to it this becomes second nature. Carry your kit lens for those odd occasions when you can't move physically closer to the subject.

In addition primes, such as the 50mm you note, are always faster as well. There is no substitute for speed. They permit you to get shots that just aren’t possible with a lesser lens. Get a 50mm 1.4 or 1.7 (normal) lens to start with. Pentax makes some of the best 50mm lenses ever made. Old manual focus ones are cheap and readily available on Ebay. The DA 50mm 1.4 goes for about $200 I believe. You will be amazed at the image quality.

As for wide-angle primes they are readily available as well. There are all kinds of manual focus Pentax lenses available from 15mm on up. More modern lens such as the DA 14mm or DA 21mm will also serve. Check the lens review database on this forum for details and evaluations. A word of warning is in order here. Once you get your first prime a disease called lens-buying addiction (LBA) is sure to set in. There is no known cure.

Cheers,

Tom G

---

Last edited by 8540tomg; 07-23-2008 at 03:33 PM. Reason: typo

[rparmar]

That being said, some argue the best zoom ever made was your two feet.

Would people stop saying this? Changing your perspective on a scene by moving your body is not the same as staying where you are, keeping the same perspective and zooming to change your field of view. This is a misunderstanding of basic photographic principles.

Not to mention that if you're near a steep drop in the Grand Canyon "zooming with your feet" might just kill you.

(Sorry, Tom, don't mean to pick on you specifically.)

In addition primes, such as the 50mm you note, are always faster as well. There is no substitute for speed. They permit you to get shots that just aren’t possible with a lesser lens. Get a 50mm 1.4 or 1.7 (normal) lens to start with. Pentax makes some of the best 50mm lenses ever made.

Now this is definitively true. If you want to play around with small DOF you need a fast prime. If you want to capture an image in a dark place you need a fast prime. And if you want a bright viewfinder image no matter where you are, you need a fast prime.

Zooms can be darned convenient though. And the IQ can be excellent these days.

[Arpe]

"Zoom with your feet"
And besides, using your feet to turn that little zoom ring on your lens is really really difficult.

[8540tomg]

"Zoom with your feet"
And besides, using your feet to turn that little zoom ring on your lens is really really difficult.

Arpe,

Not for the truly gifted.

Cheers,

Tom G

[krs]

I support picking up a prime or two and just "playing" with it. I bought a M-50mm/1.7 and a Sears 135mm/2.8 for very little money and learned a lot (still need to learn a lot more!!). I have recently bought the DA -50mm/1.4, and my initial take is that I really like it! Going to F1.4 I think will prove to be very handy, although there is certainly the tradeoff of shallow depth-of-field.

I don't think primes are the only answer though... I am itching to by a Sigma or Tamron zoom to 200mm with a constant F2.8!

[wlank]

Would people stop saying this? Changing your perspective on a scene by moving your body is not the same as staying where you are, keeping the same perspective and zooming to change your field of view. This is a misunderstanding of basic photographic principles.

Not to mention that if you're near a steep drop in the Grand Canyon "zooming with your feet" might just kill you.

Ah, the old "Foot Zoom" topic. No, people will NOT stop saying this.

While I can well imagine a C***n or N***n user falling to his/her destruction while Foot Zooming at the Grand Canyon, a Pentaxian is obviously far too bright to make such an error.

Bill

[gkopeliadis]

...a Pentaxian is obviously far too bright to make such an error.

Ahem! I can see a little racism in here

[audiobomber]

I object to the "primes are always faster" statement. Clearly that's not true.

Barcud, I like primes AND zooms. they each have benefits. I can't see having a kit that doesn't include both. Adding a 50mm F/1.4 to your existing kit would give you higher image quality, an ideal portrait lens and the capability of shooting in low light. Those would be more important factors to me than a new 17-70mm zoom.

[Wheatfield]

Can you get wide angle prime lenses ?

If you get a 50mm prime for example do you have to move towards the subject until it fills as much of the frame as you want ? Is a lot of cropping involved ? Isn't this very restrictive ?

BARCUD

At the moment, the widest Pentax prime lens you can buy is 14mm. It is quite a good lens.

Composition is all about moving the camera until you get what you want, I rarely crop very much, I prefer to get it right in camera.
I don't find prime use restrictive from a photographic sense. To be fair to the question though, my prime lenses are fairly closely spaced WRT focal length and I have a fairly extensive lens kit to go to, so if one lens is too long or short, I switch to one that is closer to what I want.

To stray a bit into conversation, I think in the very wide angle range, one is probably better off with a good zoom lens such as the DA12-24. The quality hit is very slight, and there just aren't a lot of primes available to cover a range of focal lengths in the very wide end of things.

[rparmar]

I object to the "primes are always faster" statement. Clearly that's not true.

Maybe the meaning was "for a given focal length there is always a faster prime than zoom available." Though even that is not literally true, since one can get 16mm f/2.8 in a zoom but not a prime. Still, as a generalisation it is useful.

[8540tomg]

Maybe the meaning was "for a given focal length there is always a faster prime than zoom available." Though even that is not literally true, since one can get 16mm f/2.8 in a zoom but not a prime. Still, as a generalisation it is useful.

Yes rparmar this was my intent with that statement and as a rule of thumb it holds true if you look at the recent Pentax Lens Roadmap and current lens offerings. Aside from the very expensive DA* 16~50 2.8 and DA* 50~135 2.8 the rest of the Pentax zoom line-up is pretty sluggish. For example:

16~45 f4
18~55 f3.5-5.6
10~17 f3.5-4.5
12~24 f 4
50~200 f4.5-5.6

I'm not that familiar with other maker’s offerings but this is a Pentax forum after all.

Now some of the currently available Pentax primes:

14 f2.8
21 f 3.2 (granted this is pretty sad for a prime)
31 f 1.8
35 f2.8 macro
40 f 2.8
41 f 1.9
50 1.4
70 f 2.4
77 f 1.8
100 f 2.8 macro
200 f 2.8

Plus a host of fast glass from earlier series: 24 2.8, 28 f2, 35 f2, 50 1:1.2, 85 1.4, 85 1.8, 85 f2, 105 2.8, 135 1.8, 200 2.5, 200 2.8, 300 2.8, 400 2.8 and so on. Forgive me if I missed a personal favourite.

The numbers speak for themselves. Audiobomber is correct - zooms and primes both have their place. I have a couple of zooms in my collection. My personal preference though is to reach for the fastest prime in my bag whenever possible.

Cheers,

Tom G

[Classvino]

...Aside from the very expensive DA* 16~50 2.8 and DA* 50~135 2.8 the rest of the Pentax zoom line-up is pretty sluggish...

Prices approximate, and at a store - may be cheaper on eBay.

The 16-50 goes for $800 and the 50-135 for $850.

21 f 3.2 $400
31 f 1.8 $870
35 f2.8 macro $400
40 f 2.8 $270
43 f 1.9 $850
50 1.4 $200
70 f 2.4 $480
77 f 1.8 $680
100 f 2.8 macro $480
200 f 2.8 $950

Unless money's no object, it's arguably much more economical to buy the "very expensive" zooms, than a bag full of primes. Or at least it just may be when they can produce like the DA* zooms, since you're not really sacrificing very much in IQ over any of the affordable primes. I've read about and seen the results of the 43mm and 77mm primes - they are incredible lenses, but they cost as much as a DA* zoom anyway. So for $1500 you get the best 43mm and 77mm lenses money can buy; or for an extra $100, a stop less, and a small hit in IQ, you could have the full range from 16mm to 135mm...

I'm not arguing the value of a good prime kit. If I could afford it, I'd own all 6 LTD's, the macros, and a few others; but my pocketbook says to stick with the best I can afford.

The numbers speak for themselves.

Yes. They do.

Dif'rent strokes, they say...