Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
06-03-2009, 12:31 PM   #1
Veteran Member




Join Date: Nov 2007
Location: Trinidad and Tobago
Posts: 421
1 more 18-250 question

i was refering to photozone MTF results, and i see that the results on this lens in Tamron brand yield good results in nikon and canon. where as the pentax version was gust ok
does this mean the tamron would be a better choice

Dave

06-03-2009, 02:24 PM   #2
Pentaxian
Marc Sabatella's Avatar

Join Date: Sep 2006
Location: Denver, CO
Photos: Gallery
Posts: 10,686
No, it means you need to pay attention to the warnings on photozone.de not to compare numbers between brnads. They are all the same lens, so if you're seeing different numbers, that just shows they are measuring differentl (or happened to get a better copy of the lens for one brand than another).
06-03-2009, 02:35 PM   #3
Veteran Member
Venturi's Avatar

Join Date: Mar 2008
Location: Tulsa, OK
Photos: Gallery
Posts: 2,639
Assuming the price difference between going with Tamron vs Pentax versions is negligible the only real difference between them (to me) is:
- Pentax version gives you SMC coatings.
- Tamron version give you a 6 year warranty.
06-03-2009, 03:19 PM   #4
Veteran Member




Join Date: Nov 2007
Location: Trinidad and Tobago
Posts: 421
Original Poster
QuoteOriginally posted by Marc Sabatella Quote
No, it means you need to pay attention to the warnings on photozone.de not to compare numbers between brnads. They are all the same lens, so if you're seeing different numbers, that just shows they are measuring differentl (or happened to get a better copy of the lens for one brand than another).
QuoteOriginally posted by Venturi Quote
Assuming the price difference between going with Tamron vs Pentax versions is negligible the only real difference between them (to me) is:
- Pentax version gives you SMC coatings.
- Tamron version give you a 6 year warranty.

taking these two replies into one
if photozone got a better copy of the pentax version, would it have more or less give the same results ? as the tamron test in nikon and canon ( which showed almost similar results )
price is not an issue, smc would be nice, 6 year warranty i dont care for.

Dave

06-03-2009, 11:50 PM   #5
Veteran Member
causey's Avatar

Join Date: Feb 2009
Location: Arlington, VA
Photos: Albums
Posts: 3,758
Take the Pentax 18-250mm. See the difference in rating here on pentaxforums. I think SMC is important. Plus: DxO standard will automatically correct your shots taken with Pentax and K20d/K10d.
06-04-2009, 02:20 PM   #6
Veteran Member
kristoffon's Avatar

Join Date: Aug 2008
Location: Brazil
Posts: 532
I have a better idea: stop measurebating and choose lenses based on actual pictures and other user's opinions.
06-04-2009, 02:29 PM   #7
Pentaxian
Marc Sabatella's Avatar

Join Date: Sep 2006
Location: Denver, CO
Photos: Gallery
Posts: 10,686
QuoteOriginally posted by dafiryde Quote
if photozone got a better copy of the pentax version, would it have more or less give the same results ? as the tamron test in nikon and canon ( which showed almost similar results )
That depends entirely on the cameras used and how they have each set up for testing. That's why they specifically say not to comapre numbers between brands.

The same lens is the same lens, period. You shouldn't need someone to construct test systems to produce similar numbers using different cameras in order to accept that changing some mechanical bits and pieces on the bottom of the lens to get it to fit one camera versus another isn't going to affects its actual performance.
06-04-2009, 02:48 PM   #8
Veteran Member
pcarfan's Avatar

Join Date: Sep 2007
Location: Dayton, Ohio
Photos: Gallery | Albums
Posts: 2,958
QuoteOriginally posted by Venturi Quote
Assuming the price difference between going with Tamron vs Pentax versions is negligible the only real difference between them (to me) is:
- Pentax version gives you SMC coatings.
- Tamron version give you a 6 year warranty.
Pentax does not give you SMC coatings.

06-04-2009, 02:54 PM   #9
Veteran Member
netuser's Avatar

Join Date: Oct 2008
Location: Azores Islands, Portugal
Photos: Gallery
Posts: 2,241
Go for DA 18-250 for the coating
PENTAX Photo Gallery
06-04-2009, 03:10 PM   #10
Veteran Member
Venturi's Avatar

Join Date: Mar 2008
Location: Tulsa, OK
Photos: Gallery
Posts: 2,639
QuoteOriginally posted by pcarfan Quote
Pentax does not give you SMC coatings.
Then why is it's moniker "smc PENTAX DA 18-250mm f/3.5-6.3 ED AL [IF]"?

I have yet to see any concrete evidence suggesting that any lens in the current lineup lack SMC lens coatings. The highlights and spec notes on some mention "SP coatings" but not with consistency of placement. I could very well be wrong and it would be good to know "the facts" or at least where to find the detailed specifics so if you can provide either by all means please share.
06-04-2009, 03:57 PM   #11
Veteran Member




Join Date: Nov 2007
Location: Trinidad and Tobago
Posts: 421
Original Poster
QuoteOriginally posted by kristoffon Quote
I have a better idea: stop measurebating and choose lenses based on actual pictures and other user's opinions.
i see you have the K20D and the 18-250, can you give a personal review of that combo

Dave
06-04-2009, 04:06 PM   #12
Veteran Member




Join Date: Nov 2007
Location: Trinidad and Tobago
Posts: 421
Original Poster
QuoteOriginally posted by Marc Sabatella Quote
That depends entirely on the cameras used and how they have each set up for testing. That's why they specifically say not to comapre numbers between brands.

The same lens is the same lens, period. You shouldn't need someone to construct test systems to produce similar numbers using different cameras in order to accept that changing some mechanical bits and pieces on the bottom of the lens to get it to fit one camera versus another isn't going to affects its actual performance.
i agree, a lens is a lens, of the same make same brand. i was not looking for a straight over the board , exact results.
what i did notice in the tamron brand, between canon and nikon, the tamron more or less gave similar results, give or take.
where as the pentax brand, gave way different results, so i wonder
1 did photozone get good coppies for the canon and nikon in tamron.
2 did photozone get a bad copy of the pentax.


Dave
06-04-2009, 06:05 PM   #13
Veteran Member




Join Date: Mar 2007
Location: Toronto (for now)
Posts: 1,749
It says SMC but it behaves like a Tamron lens not a Pentax lens. The colour is flat, lifeless and somewhat lacking in greens and blues. Even the 18-55 kit lens does a btter job colour wise IMHO.
06-04-2009, 06:39 PM   #14
Veteran Member
pcarfan's Avatar

Join Date: Sep 2007
Location: Dayton, Ohio
Photos: Gallery | Albums
Posts: 2,958
QuoteOriginally posted by Venturi Quote
Then why is it's moniker "smc PENTAX DA 18-250mm f/3.5-6.3 ED AL [IF]"?

I have yet to see any concrete evidence suggesting that any lens in the current lineup lack SMC lens coatings. The highlights and spec notes on some mention "SP coatings" but not with consistency of placement. I could very well be wrong and it would be good to know "the facts" or at least where to find the detailed specifics so if you can provide either by all means please share.
It's just that people who have looked at both lenses side by side had noted the the color of the coatings to be the same between the two lenses and it was the same color as that of all Tamron lenses they had and the color is not the same as the pentax SMC coatings of the lenses they had. After reading this first hand knowledge, I decided it was safe to assume pentax did not change the coating.

I know I've read of posts showing how pentax has used SMS in lenses that didn't have it. Let me try to dig that up.
06-04-2009, 06:50 PM   #15
Veteran Member
kristoffon's Avatar

Join Date: Aug 2008
Location: Brazil
Posts: 532
QuoteOriginally posted by dafiryde Quote
i see you have the K20D and the 18-250, can you give a personal review of that combo

Dave
There's a review I did on the 18-250 on the site's review section for this lens if you want to take a look there.

In short, it's a VERY good lens: sharp stopped down, unbeatable zoom range. I LOVE prime lenses and yet the 18-250 seems to stick to my camera like glue - that should tell you something.

HOWEVER, you must accept its limitations: some noticeable barrel distortion at 18mm, and CA at the long end and vignetting unless stopped down. Vignetting is easily corrected if shooting raw though. Also, noticeably soft wide open.

Accept this lens shines from f/8 to f/11 and you'll be a happy camper.

My flickr set for this lens, all shots available in very high resolution.

Also I must praise its flare control. I never use the hood anymore since there's no flare. Ever. Even if the Sun is inside the frame, then you'll notice a couple small spots. See the picture below for an example (this is with the K200D):



Another one, with the K20D this time:



Hope I have helped.

Last edited by kristoffon; 06-04-2009 at 06:58 PM.
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!
k-mount, pentax lens, results, slr lens, tamron
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Magnification Question: Reversed 50mm vs. Raynox 250 twokatmew Troubleshooting and Beginner Help 2 07-18-2010 04:15 PM
pentax 18-250 question diego604 Pentax SLR Lens Discussion 14 12-10-2009 01:57 PM
18-250 question gokenin Pentax SLR Lens Discussion 27 01-18-2008 05:15 AM
Another 18-250 question, sorry !! simonkit Pentax SLR Lens Discussion 11 12-24-2007 10:52 AM
Tamron18-250 or Sigma17-70 (Range or Speed thats the question) Salminus Pentax DSLR Discussion 23 09-25-2007 11:45 PM



All times are GMT -7. The time now is 02:40 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