Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
04-05-2011, 05:26 PM   #1
Pentaxian
littledrawe's Avatar

Join Date: Jan 2010
Location: Red Rock
Photos: Gallery | Albums
Posts: 2,434
Did I get a good copy tamron 10-24, your opinion please?

Tamron 10-24 that I bought used from adorama on my K2000. I have heard about corner and edge softness but I thought I would gamble on this one, what do you think?

Attached Images
         

Last edited by littledrawe; 04-06-2011 at 05:09 PM. Reason: more descriptive
04-05-2011, 05:34 PM   #2
Pentaxian
v5planet's Avatar

Join Date: Jan 2010
Location: Seattle
Photos: Albums
Posts: 1,904
If your concern is the corner softness, these images may not be the best type to make an assessment off of. The reason is that with the exception of the first, the corners are all way out of the depth of field, i.e. you're focused on something close and the objects in the corners are further away. They're already out of focus so you can't make a great assessment on how sharp the corners are. You need to make sure they are inside the depth of field first.
04-05-2011, 05:51 PM   #3
Pentaxian
littledrawe's Avatar

Join Date: Jan 2010
Location: Red Rock
Photos: Gallery | Albums
Posts: 2,434
Original Poster
are these better?

I was just trying to get some stuff to test so maybe I need to go out again with it and get some different images.
Attached Images
         
04-05-2011, 05:55 PM   #4
Veteran Member
RioRico's Avatar

Join Date: Jun 2008
Location: Limbo, California
Posts: 11,264
v5planet is quite right. To test the corners and edges, shoot perpendicular to something flat, like a brick wall. Your targets need to have stuff with details at corners and edges -- blank concrete won't do! It you're serious, use a tripod with level, or a test bench.

--Rio(I haven't had a chance to rigorously test my 10-24 yet either)Rico

04-05-2011, 05:57 PM   #5
Veteran Member
PGillin's Avatar

Join Date: Apr 2010
Location: South Florida, USA
Photos: Albums
Posts: 336
All of the images in your first post have strong composition, they're all good pictures and they look good.
What does this mean? You're making the lens work with you and fit your shooting style.
The verdict: Keep it. Worry about corner sharpness later if it becomes noticeable or problematic.
04-06-2011, 05:07 PM   #6
Pentaxian
littledrawe's Avatar

Join Date: Jan 2010
Location: Red Rock
Photos: Gallery | Albums
Posts: 2,434
Original Poster
brick wall as suggested earlier

first one is at f3.5, second one is at f5.6, third one is at f8.0, fourth one is at f11, fifth one is at f13. seems to me that it is quite soft on the upper border and corners and only gets usable after f11. but I am wondering what other peoples opinions are.
this test was done with a tripod, 2 second delay shutter release and manual focus set to infinity at 10mm focal length throughout the series.
Attached Images
         
04-06-2011, 05:56 PM   #7
Junior Member




Join Date: Nov 2009
Location: Montreal
Posts: 44
I have the impression you're not perpendicular to the wall but at a slight angle... the left corners seem to be slightly out of focus on the wider aperture shots.
04-06-2011, 06:39 PM   #8
Senior Member




Join Date: Nov 2009
Location: Marin, CA
Photos: Gallery | Albums
Posts: 281
I returned two Tamron 10-24's due to ridiculously awful softness in the corners. I could have just had bad luck, but I was not happy with mine at all. RioRico, I can't believe you still haven't tested yours? What if it's a bad copy? Isn't it too late to return now?

Anyway. Try shooting indoors. Test some shots of your kitchen, with good overhead light. Does it look soft in the corners? Those brick wall shots look a bit soft, but not nearly as bad as mine came out.

04-06-2011, 07:49 PM   #9
Forum Member
feilb's Avatar

Join Date: Mar 2011
Location: Milwaukee, WI
Posts: 83
Ultimately, if you are happy with the results, it shouldn't matter if the lens is technically perfect. That being said, I thought the first set of pics you posted looked great. Stopped down It definitely looked sharp.
04-06-2011, 10:04 PM   #10
Veteran Member
Pentaxor's Avatar

Join Date: May 2009
Location: Vancouver, B.C.
Photos: Gallery
Posts: 6,513
if you are unhappy with it's performance at wider openings, get the Pentax DA12-24.
04-07-2011, 07:26 AM   #11
Veteran Member
Eruditass's Avatar

Join Date: Jul 2009
Location: Pittsburgh, PA
Photos: Gallery | Albums
Posts: 2,206
Make sure to account for focus field curvature..

Probably accounts for most peoples' complaints of corner softness. When comparing corners, you need to manual focus to get the corners in focus without recomposing. Liveview can help.

Last edited by Eruditass; 04-07-2011 at 09:24 AM.
04-07-2011, 08:52 AM   #12
Veteran Member
Jewelltrail's Avatar

Join Date: May 2008
Location: Rhode Island
Photos: Albums
Posts: 4,180
I have seen copies which are very, very poor in the corners--disgraceful actually---but those are obvious. This one is not bad. Shooting perfectly flat subjects is silly & proves nothing: reality is not two-dimensional, yet forum member after member continue to judge their lens based on non-reality.

Moreover, some lenses are very sharp to the corners, but have field curvatures--this means shots of perfectly flat subjects will make the lens look bad, even though lens is good. A field curvature often has no bearing on real life shots. Shooting reality is about 3 dimensions, so this is where you take test shots. Photozone goes as far as to say that probably no lens is technically perfect, that they all have a centering problem to one degree or another. People are hung up on perfection, though God knows why because none of us are perfect.

As others have said, take real life shots, and ask yourself if you are happy--you spend the money--you are the judge. If you bought from a good dealer, exchanging for another will not be a problem. Worst thing you can do, is be unhappy with the lens & hang onto it out of uncertainty: make a decision which makes you happy. Either try another lens, or return for your money back.

EDIT:
QuoteQuote:
Pentaxor: if you are unhappy with it's performance at wider openings, get the Pentax DA12-24.
The Sigma Ultra wide angle choices are also excellent, should you decide the Tamron is not what you want. Lots of pics in the Sigma 10-20 & 8-16 Clubs if you need them. Good luck!

Last edited by Jewelltrail; 04-07-2011 at 09:11 AM.
04-09-2011, 10:23 PM   #13
Pentaxian




Join Date: Apr 2007
Location: Oklahoma USA
Posts: 1,476
There seems to be a lot of sample variation in these somewhat extreme lenses; I've experienced the same with Pentax and Sigma lenses. It's almost true that the sample you have is more important than the model or brand you have.

Having said that, I think most sample problems show up as variation across the field. If the center is sharp and all the corners fuzzy, particularly wide open, that may just be what the lens does. But if one side or corner is much different from others, that's probably a sample variation issue. So that's really what you want to be looking for. If you see no variations but aren't happy, I'd be tempted to try a different make or model lens, not just another of the same.

With my 10-20mm sigma (old version), I found it is not much use to test at close distances, because with the angle being so wide, the edges are at a much different distance than the center. Instead I tried more distant subjects. I've used distant traffic or building signs. Also at least with the Sigma, neither of my bodies can focus reliably at 10mm, so I use manual focus (which is also not reliable, but is at least consistent shot-to-shot, if you don't touch the lens.)

Paul
04-09-2011, 10:39 PM   #14
Veteran Member
Pentaxor's Avatar

Join Date: May 2009
Location: Vancouver, B.C.
Photos: Gallery
Posts: 6,513
this is exactly the reason why the Tamron 10-24 is not highly recommended among the UW options. it just fails in both consistency and IQ rendering and preference.
04-10-2011, 02:46 PM   #15
Pentaxian




Join Date: Apr 2007
Location: Oklahoma USA
Posts: 1,476
Overall it does seem that the Tamron is not the most favored of lenses, whereas the Sigma (old variable aperture) seems to be hit or miss depending on the particular lens you get. A number of posts seem to express disappointment in the Tamron, despite it being a somewhat more modern lens, and with the family having an overall good reputation. There are probably not enough samples of the 8-16 Sigma to draw any conclusions, but it is in a somewhat different category. The 12mm Pentax/Tokina is also in a different category, in that there is such a huge difference between 10mm and 12mm. Everyone seems to wish that Pentax would just sell the 11-16 Tokina, but that seems not to be happening.

Paul
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, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
How does one know if they have a good lens copy? DanWeso Pentax SLR Lens Discussion 5 01-02-2011 10:40 PM
Testing a new lens: good or bad copy? Edmund Pentax SLR Lens Discussion 3 06-13-2010 10:30 PM
what is a good or bad copy of Da*16-50? nuaabill Pentax SLR Lens Discussion 20 11-13-2009 07:26 PM
For Sale - Sold: (AUS) DA* 16-50mm (good copy) bonovox Sold Items 8 09-17-2009 01:26 AM
What are the odds that my new 16-50 will be a good copy skinja Pentax SLR Lens Discussion 10 05-20-2009 05:07 PM



All times are GMT -7. The time now is 07:33 AM. | See also: NikonForums.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