Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
11-10-2013, 07:11 PM - 3 Likes   #1
Site Supporter
rbefly's Avatar

Join Date: Oct 2009
Location: Denver, Colorado
Photos: Albums
Posts: 2,030
DA 20-40mm Ltd. By The Numbers?

First off, I don't have any amazing insights, insider information or even self-indulgent, official-sounding proclamations to make regarding the performance of this lens. For that (and much more!) you can click on either the 52-page thread, the 131-page thread or (time permitting) the 774-page thread.
What I DO have, and haven't seen posted yet, are numbers. As in, size, weight, aperture, filter size and (of course!) price.
But we already have those numbers, right?
For the Pentax DA Limited 20-40mm f/2.8-4.0 zoom, yes we do. I meant the numbers for Canon and Nikon. You know, the 'other guys'?
Neither one offers an exact 20-40mm match, but between them, they have four lenses that come pretty close. One Nikon and one Canon are constant f/2.8, the another pair are constant f/4.0. What may (or, may not) surprise you is that the new DA is faster (overall) than two, smaller and lighter than all four and (drum roll, please!) less expensive than three, within $160 of the fourth. Oh, one other difference; All 4 C/N's are APS-C and FF compatable. We'll have to wait to see if the Pentax is or is not. Meaning the DA zoom may vignette on a camera that Pentax doesn't offer anyway, at least right now. That makes perfect sense to me. YMMV.
As promised;
Pentax DA Limited 20-40mm f/2.8-4.0 zoom. Filter 55mm, size 71 x 68.5mm, weight 283 gr, 10.0 oz. Price $1,000. W/R, DC motor.
Canon EF 16-35mm f/2.8L zoom. Filter 82mm, size 88.5 x 111.6mm, weight 635 gr, 23 oz. Price $ 1,700. W/R, USM.
Canon EF 17-40mm f/4.0L USM zoom. Filter 77mm, size 83.5 x 96.8mm, weight 475 gr, 16.2 oz. Price $840. W/R, USM.
Nikon 17-35mm f/2.8 ED-IF zoom. Filter 77mm, size 83.8 x 106.7mm, weight 745 gr, 26 oz. Price $1,450. W/R, SWM.
Nikon 16-35mm f/4.0 ED-VR zoom. Filter 77m, size 81.3 x 124.5mm, weight 680 gr 24.5 0z. Price $ 1,250. SWM.
Disclaimer; Prices, weights and sizes are from B + H Photo, they may vary slightly on other sites. Weight conversions are accurate in grams (from B + H, again), my ounce(s) conversions may not be!.
What I'm able to deduce from this is that Ricoh/Pentax tried to hit the middle of these offerings. The DA Ltd's variable-aperture, so derided by many, permitted a much smaller lens in every dimension. It may also have helped the size and price factors that the FL doesn't go as wide as the Nikon/Canon offerings, perhaps better-informed minds, regarding manufacturing and design costs of WA zooms could could enlighten us further. Compared to the constant f/2.8 zooms, it's one stop slower at the long FL's, equal at 20mm. Compared to the constant f/4.0 lenses, it's faster at 20mm and equal at the longer FL's. A compromise. The price is very competitive; slightly more than the f/4.0 Canon, less than any of the others. How it compares optically, we'll have to wait and see.
Ron


Last edited by rbefly; 11-11-2013 at 04:02 AM. Reason: Add new data
11-10-2013, 07:16 PM   #2
Pentaxian
seventysixersfan's Avatar

Join Date: Aug 2010
Location: Alexandria, VA
Posts: 1,704
I am not familiar with nikon and canon lenses-- do the ones you listed have Weather resistance and silent focusing motoring? What about Construction material -- are they plastic or metal?
11-10-2013, 07:40 PM   #3
Pentaxian




Join Date: Jul 2012
Location: Albuquerque
Posts: 1,120
Compact Camera Meter

(Pentax 18-55mm has similar dimensions as the 20-40mm).
11-10-2013, 07:45 PM   #4
Site Supporter
rbefly's Avatar

Join Date: Oct 2009
Location: Denver, Colorado
Photos: Albums
Posts: 2,030
Original Poster
Good Question!

QuoteOriginally posted by seventysixersfan Quote
I am not familiar with nikon and canon lenses-- do the ones you listed have Weather resistance and silent focusing motoring? What about Construction material -- are they plastic or metal?
Hi seventysixersfan,
To be honest, I don't know about the WR, focusing motors and construction. I'll have to research the individual Canon and Nikon sites to find out. Good question, though! I'll post (here) when I get some data.
Ron

11-10-2013, 07:58 PM - 1 Like   #5
Pentaxian
seventysixersfan's Avatar

Join Date: Aug 2010
Location: Alexandria, VA
Posts: 1,704
Otherwise you do make a good point in comparing sizes, weight, speed, and most importantly, price. Maybe $1000 is not too unreasonable....
11-10-2013, 08:29 PM   #6
Pentaxian
carrrlangas's Avatar

Join Date: Mar 2012
Location: Cottbus (Berlin)
Photos: Gallery
Posts: 1,738
But... Comparing full frame lenses to an APS-C specific (weīll have to wait for the tests to see if it covers FF image circle) doesnīt make much sense to me because of different Angle of view and all things that come with that (max aperture, size, weight, etc).
Shouldnīt we look for 30-60mm zooms if looking at FF glass? are there any? 24-50 comes to mind but 24 is pretty wide compared to 30...
11-10-2013, 08:47 PM   #7
Site Supporter
SpecialK's Avatar

Join Date: Dec 2006
Location: So California
Photos: Gallery
Posts: 14,627
QuoteQuote:
Shouldnīt we look for 30-60mm zooms if looking at FF glass?
The crop factor applies to all lenses equally, so no.
11-10-2013, 08:51 PM   #8
Pentaxian
carrrlangas's Avatar

Join Date: Mar 2012
Location: Cottbus (Berlin)
Photos: Gallery
Posts: 1,738
QuoteOriginally posted by SpecialK Quote
The crop factor applies to all lenses equally, so no.
but, FF glass in the 20-40mm range will always be heavier, bigger, slower... it has to cover a bigger circle... Althogh If you only use a crop sensor, then yes... itīs the same thing...

11-10-2013, 09:33 PM   #9
Site Supporter
rbefly's Avatar

Join Date: Oct 2009
Location: Denver, Colorado
Photos: Albums
Posts: 2,030
Original Poster
APS vs FF?

QuoteOriginally posted by carrrlangas Quote
but, FF glass in the 20-40mm range will always be heavier, bigger, slower... it has to cover a bigger circle... Althogh If you only use a crop sensor, then yes... itīs the same thing...
Hello carriangas,
Yes, I'm trying to compare the (closest focal range) Nikon and Canon wide-angle zooms to the new DA Ltd zoom. Pentax can hardly be criticized for an unfair comparison, simply because Canon and Nikon chose to make their lenses fit two different formats. Pentax made the DA to fit the cameras they offer.
Canon and Nikon seem to actively be steering their users towards FF, and have minimal new offerings in the cropped-format (only) lens lineup. If they choose to follow this course, they will leave a void in the smaller format and Pentax can use it to introduce a fuller and more varied APS-C lens selection.
Their loss is our gain!
Ron

Last edited by rbefly; 11-10-2013 at 09:44 PM.
11-10-2013, 09:43 PM   #10
Pentaxian
carrrlangas's Avatar

Join Date: Mar 2012
Location: Cottbus (Berlin)
Photos: Gallery
Posts: 1,738
True, and good point. Itīs just good to clarify that the comparison only applies for crop sensor cameras.
11-11-2013, 01:02 AM   #11
Pentaxian
starbase218's Avatar

Join Date: Sep 2009
Location: Planet Earth, Sol system, Milky Way galaxy, Universe
Posts: 1,110
QuoteOriginally posted by SpecialK Quote
The crop factor applies to all lenses equally, so no.
That is assuming you would use these C/N lenses on a crop body, while they are designed to cover fullframe. Not really a fair comparison imho.
11-11-2013, 01:11 AM - 1 Like   #12
Pentaxian
thibs's Avatar

Join Date: Jun 2007
Location: Belgium
Photos: Albums
Posts: 5,206
QuoteOriginally posted by starbase218 Quote
That is assuming you would use these C/N lenses on a crop body, while they are designed to cover fullframe. Not really a fair comparison imho.
It is if it is clear you compair in this context.
You could do the same on an FF bofy and you'd (most probably) get the DA Limited to vignette so badly the FF lenses would take a good laugh.

I see no problem in this comparison. As long as it is clear you're working on a specific format: APS-C.
11-11-2013, 01:52 AM - 1 Like   #13
Veteran Member




Join Date: Oct 2011
Posts: 818
Hmm....

Why is it that i have to pay for a whole cheese when all i need are a few slices?

Last edited by SyncGuy; 11-11-2013 at 02:00 AM.
11-11-2013, 02:56 AM   #14
Site Supporter
MBT74's Avatar

Join Date: Sep 2012
Posts: 135
The numbers I'd like to see are the f stops for each focal length range. Is only 20mm at f2.8? What the max f stop at 25mm etc?
11-11-2013, 04:26 AM - 2 Likes   #15
Site Supporter
rbefly's Avatar

Join Date: Oct 2009
Location: Denver, Colorado
Photos: Albums
Posts: 2,030
Original Poster
More Info

QuoteOriginally posted by seventysixersfan Quote
Otherwise you do make a good point in comparing sizes, weight, speed, and most importantly, price. Maybe $1000 is not too unreasonable....
For seventysixersfan and any others who may be interested, I took a look at the Canon and Nikon home sites regarding the construction features of the four lenses. Here's what I found;
Both Canon zooms feature the 'Ultra Sonic Monitor' (USM) which reduces focusing noise. I don't know how this compares to the DC motor used in the new DA Ltd zoom, but would assume they're both pretty quiet.
Both Canon zooms are described as 'Weather-Resistant'
The Nikon 17-35mm f/2.8 zoom features a 'Silent Wave Motor' (SWM) for focusing. It is described as having a 'rugged construction and professional grade dust and moisture resistance to withstand even the most trying conditions'. I've shortened this to 'W/R' on the first post.
The Nikon 16-35mm f/4.0 zoom features SWM.
Neither site goes into detail about metal/plastic used in the lens construction. I would guess (always a dangerous tactic!) the higher-priced f/2.8 zooms, clearly aimed at the advanced/pro market, are more sturdy than the f/4.0 versions. How much metal/plastic/composite materials and in what ratios? Got me.
I've added the focusing motor initials and 'W/R' for all lenses in the initial comparisons, where appropriate.
Ron
Reply

Bookmarks
  • 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!
20-40mm, canon, da, filter, gr, nikon, oz, pentax news, pentax rumors, price, size, weight
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Thematic By the numbers charliezap Mini-Challenges, Games, and Photo Stories 287 01-29-2017 06:16 PM
DA 40mm LTD. is the perfect walk-around lens tele_pathic Pentax SLR Lens Discussion 17 11-18-2013 10:40 AM
Is there a comparison between the DA 40mm LTD and the 40mm XS out there anywhere? ChopperCharles Pentax SLR Lens Discussion 9 05-07-2012 11:07 AM
For Sale - Sold: Brand New in Box: DA 15mm ltd, DA 40mm ltd, DA 17-70mm, DA 18-55mm WR chemxaj Sold Items 8 12-01-2009 02:16 PM
For Sale - Sold: DA 40mm ltd and DA 35mm Macro ltd (caution: large images) farfisa Sold Items 7 02-06-2009 07:21 AM



All times are GMT -7. The time now is 09:32 AM. | See also: NikonForums.com, CanonForums.com 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?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top