Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
06-16-2010, 05:15 PM   #1
Veteran Member
raider's Avatar

Join Date: Jul 2007
Location: Perth, Australia
Photos: Gallery
Posts: 1,941
What is the advantage of 21/35/40 prime vs a f2.8 zoom lens


I have not owned any prime lens (except the DA14) and I would like to get the DA35 Ltd (and possibly the DA21) after my tax return. Like usual, all lens purchase must get the finance minister's approval and this time wifey posed this challenging question to me (now that she is also into photography) and I just could not answer.

She said that i already have a f2.8 zoom lens that cover the range between 21, 35 and 40 and at a fixed aperture of 2.8. I said that prime lenses are sharper and the DA35 has macro. She said that i am just nuts and those lenses i want are unjustified purchases.

I said the prime lenses are great for traveling on short trips. She said that surely a single f2.8 zoom lens is much more convenient that a couple of smaller prime lenses....

What do you guys I just becoming another LBA addict (again?)

06-16-2010, 05:30 PM   #2
Veteran Member

Join Date: Aug 2007
Location: Ottawa
Posts: 365
Point out that primes can sometimes be faster than the 2.8 zoom. Case in point: The FA 50 comes in f1.4 and f1.7 flavours. Also, there tends to be more control in distortion with prime lenses.

But she is right about a single 2.8 zoom is more practical, especially when space is an issue.
06-16-2010, 06:02 PM   #3
Veteran Member
khardur's Avatar

Join Date: Feb 2007
Location: NW Massachusetts
Photos: Gallery
Posts: 1,505
Sometimes there are other issues. Looking at jsherman's thread on the 15mm limited, I notice that flare seems practically non-existent, even shots directly into the sun, and the starburst created by bright points of light is just gorgeous.

Looking at the Tamron 17-50, sure it covers a lot more ground than just one lens, and thus is more versatile. But it does have some undesirable flare when you look at similar situations. It takes great pictures, no doubt, but just looking at the construction (16 elements in 13 groups) you can tell it would be more prone to flare than the 15mm. (8 elements, 6 groups).

So don't overlook certain intangibles there regarding image quality when attempting to justify a lens. Or get a second job for a little to pay for your lba, then at least you're not spending mortgage money on lenses. hehe..
06-16-2010, 06:22 PM   #4
Site Supporter
SpecialK's Avatar

Join Date: Dec 2006
Location: So California
Photos: Gallery
Posts: 14,906
QuoteOriginally posted by raider Quote
What do you guys I just becoming another LBA addict (again?)
Depends on what you shoot, how often you want to change lenses, how much pixel peeping you do, limitations of your existing equipment, how much you want to talk about bokeh and rendering - and your wife's OK.

06-16-2010, 07:40 PM   #5
Veteran Member
mattdm's Avatar

Join Date: Feb 2007
Location: Boston, MA
Photos: Gallery
Posts: 2,964
Well, there's this: The Online Photographer: The Case Against Zooms

But also, the DA Limited series (excepting the 35mm Macro) -- 15mm/21mm/40mm/70mm -- weighs the same in total as the 16-50mm f/2.8, and I'm pretty sure they take up less space in a camera bag, too.
06-16-2010, 08:11 PM   #6
johnmflores's Avatar

Join Date: Apr 2009
Location: Somerville, NJ
Photos: Gallery | Albums
Posts: 5,185
I use zooms when speed (the ability to quickly frame and take a shot) is critical.

I use primes when discretion (not bringing attention to one's self or intimidating subjects) is critical.

Besides, she must have some hobby or fetish (handbags, shoes, or, so as not to be completely sexist, motorcycles where she sees distinctions in products that most people don't.
06-17-2010, 03:11 AM   #7
Veteran Member
raider's Avatar

Join Date: Jul 2007
Location: Perth, Australia
Photos: Gallery
Posts: 1,941
Original Poster
Thanks for your comments. I think i know just the way to "persuade" my wife now
06-17-2010, 05:28 AM   #8
Site Supporter
Fries's Avatar

Join Date: Oct 2009
Location: Gauw
Photos: Gallery | Albums
Posts: 1,889
The bokeh of certain prime lenses can be more pleasing to the eye. And the short focussing distance of the DA 35 limited is also a plus. Just trying to help!

06-17-2010, 08:57 AM   #9
Senior Member
pontusadefjord's Avatar

Join Date: Apr 2009
Location: Uppsala
Photos: Gallery
Posts: 111
You have to move around more, so you get some exercise? I think I'm going to try that one myself...
06-17-2010, 09:11 AM   #10
Veteran Member
MrPetkus's Avatar

Join Date: Feb 2010
Location: Long Island, NY
Posts: 388
Don't know anything about your wife but many fine frugal wives (with photography experience) will be prone to:
1) Make side comments when you screw on that expensive new prime
2) Make side comments when you struggle to frame a shot while she simply zooms in
3) Make side comments when you opt for the zoom while at the focal range of the prime
4) Make side comments that the pics don't look any better than those with the zoom

Of course, these sort of women are far and few between and this is merely a cheap caricature.

However, if you
A) Get her hooked on primes
B) Make $$ with your prime pics
C) Take amazing portraits of her with the prime
the expense will be forgotten.
06-17-2010, 12:27 PM   #11
Marc Sabatella's Avatar

Join Date: Sep 2006
Location: Denver, CO
Photos: Gallery
Posts: 10,686
Easiest way I know to demonstrate the value would be to ask her to hold the camera for an hour or two with the 16-50 mounted, then do the same with a DA35 or DA21 (assuming you have access to one). Difference in IQ will be slight and subjective; differences in speed non-existent with the specific primes you are considering, but differences in size weight are immediate, obvious, and dramatic. With the 35, you could of course demonstrate macro too.

Last edited by Marc Sabatella; 06-18-2010 at 09:38 AM.
06-17-2010, 03:22 PM   #12
Site Supporter
SpecialK's Avatar

Join Date: Dec 2006
Location: So California
Photos: Gallery
Posts: 14,906
Well, there's this:
Hardly. It purports that because a zoom has a wide variety of FOVs, the user can't figure out a good one, or that you must only use the same one, or that somehow one FOV works everywhere. Pure stinkum.
06-17-2010, 03:30 PM   #13
Veteran Member
Reportage's Avatar

Join Date: Feb 2009
Photos: Gallery
Posts: 739
didnt Canon used to make a 200mm f/1.8?

I would say it was best of both worlds.
06-17-2010, 10:01 PM   #14
wizofoz's Avatar

Join Date: Apr 2009
Location: Melbourne, Outer east.
Photos: Gallery | Albums
Posts: 1,655
I don't suppose trading in the good lady wife for the primes is an option??
06-17-2010, 10:10 PM   #15
Pablom's Avatar

Join Date: Feb 2010
Location: Jerusalem
Posts: 1,940
My question is why do you want to buy a bunch of lenses that you don't know what they're good for?

  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, da35, f2.8, lens, lenses, pentax help, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
limited prime vs zoom trevorgrout Pentax SLR Lens Discussion 18 06-04-2010 01:01 PM
are you a zoom or a prime? nostatic Pentax SLR Lens Discussion 69 09-17-2009 12:51 AM
Zoom versus Prime Aaron1971 Pentax SLR Lens Discussion 17 01-03-2009 02:33 PM
Prime vs. Zoom magnum1 Pentax SLR Lens Discussion 15 11-25-2008 05:12 AM
Zoom v. Prime stafford588 Pentax SLR Lens Discussion 9 01-14-2008 04:10 AM

All times are GMT -7. The time now is 01:15 PM. | See also:, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]