Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
01-12-2008, 10:19 PM   #1
Inactive Account




Join Date: Oct 2007
Location: melb, au
Photos: Gallery
Posts: 100
Just My Luck?

got the 50-135 yesterday = me happy,
BUT the lenshood had a crack in the spring plastic, some locktite super glue fixed that no probs.
I shoot a shyte load of pics today and the gear is sharp= nice
BUT she seems to be a little off ie. back focus 4mm or so, = pain in arse when close up @ 2.8
have a look at these and tell me what we all think-worth chasing ie send back or forget it and get nikon gear<- joke
or is the camera-10D outa wak
thanks for ya help guys.
G out

Attached Images
     
01-12-2008, 10:46 PM   #2
Veteran Member
roentarre's Avatar

Join Date: Oct 2006
Location: Melbourne, Australia
Posts: 11,794
It really counts when you use the zoom outdoor.

I think this zoom will do pretty well outdoor. I would not be too concerned about this back focusing. Just bear that in mind when you are shooting. In that type of angle with dark lighting, focusing can be off.

Enjoy the zoom
01-12-2008, 11:28 PM   #3
Inactive Account




Join Date: Oct 2007
Location: melb, au
Photos: Gallery
Posts: 100
Original Poster
yep this is out door iso 100 2.8@1/2000+
i find it hard to part with 1000ish$ and have out of focus shots, and then enjoy anything. if the tool cant deliver the goods as far as sharpness is concerned then i have a major problem.

Am I justified in getting onto pentax-cr kenedy and having a go for shipping me a dodgey piece of kit or is this something in my head?

to be fair the shots are okish at f4 f5.6 and so on due to a DOF save but i do shoot most of my stuff at 2.8 hence the puchase of a 2.8 lens but if its going to focus on the back ground and not the confirmed subject then its no good to me-a virtual paper weight.
Dont get me wrong the lens is wicked sharp just that its sharp on the wrong thing, i mean ya wouldn't buy a hammer that bent every nail ya hit would you and if you did ya'd chuck it and get one that hit true.
01-13-2008, 12:35 AM   #4
Veteran Member




Join Date: Sep 2006
Photos: Gallery
Posts: 5,713
You'll pretty well never get a lens that nails the focus point, and 4mm really isn't that bad.
Although I'd ask for another lens cap

Was there any damage on the box?

01-13-2008, 12:42 AM   #5
Veteran Member
roentarre's Avatar

Join Date: Oct 2006
Location: Melbourne, Australia
Posts: 11,794
You can send it to CR Kennedy. Probably takes about 2 months or so to get it calibrated. It is based in South Yarra.
01-13-2008, 12:47 AM   #6
Inactive Account




Join Date: Oct 2007
Location: melb, au
Photos: Gallery
Posts: 100
Original Poster
when you pay for precise equipment you expect nothing less-did a test with my 16-45 f4 and its spot on.
I think I'll send this one back!
01-13-2008, 03:34 AM   #7
Veteran Member
roentarre's Avatar

Join Date: Oct 2006
Location: Melbourne, Australia
Posts: 11,794
In fact, I think my Da* 16-50 back focuses a lot more than what you had discovered from your copy. But you can have a look at my gallery of 56 shots taken by this terrific zoom.

I get by with little problems.

Da* 16-50mm f2.8 shots

Speaking of the cost associated with this lens, this is nothing comparing to my canon L gear. Most of them with incredibly fast speed autofocus but back focus. I survived.

Sometimes we cannot ask too much of a lens. Da* 16-50 is really great for its contrast and colour. And it can survive 24 hour of rain pouring on it. Using it for candids is silent, no one even notices you taking a couple of shots at them.

Hope you get a better copy.
01-13-2008, 05:53 AM   #8
Veteran Member




Join Date: Feb 2007
Location: fla
Photos: Gallery
Posts: 375
nice site roentarre,.....i am considering this lens for my spring trek ( or the 12-24 ), like you, i sometimes find that one needs to adjust to the equipment as oppossed to ' adjusting the equipment. On the other hand , if supplied with crap, then by all means correct the problem. Thanks for sharing you images, always a pleasure to take in.

01-13-2008, 06:25 AM   #9
Veteran Member
Finn's Avatar

Join Date: Feb 2007
Location: Phoenix
Photos: Gallery
Posts: 1,056
Keep in mind that the focus points on the camera are not totally precise, so that could make it seem like back focusing.
01-14-2008, 02:37 AM   #10
Inactive Account




Join Date: Oct 2007
Location: melb, au
Photos: Gallery
Posts: 100
Original Poster
cant hit the target if my sights are off.


tis gone to CRK today K10 and all will let you all know.
the guy -not tech tested it and i pointed the problem he think maybe the camera is off so he took it for the techs to have a look
01-14-2008, 02:42 AM   #11
Veteran Member
roentarre's Avatar

Join Date: Oct 2006
Location: Melbourne, Australia
Posts: 11,794
All the best to it.

But the 3 people that serve at customer service CRK are quite dodgy. I visited the centre several times and was told many inaccurate accounts of my lenses' problems. Very often, these people did not even check the real tech's reports before answering your questions...
01-14-2008, 06:41 AM   #12
Pentaxian
Lowell Goudge's Avatar

Join Date: Jan 2007
Location: Toronto
Photos: Gallery | Albums
Posts: 15,401
I did a calculation for someone, once that came up with an error in focusing of something like 3-5 microns, to give the 4mm error.

Aside from the unrealsitic expectation of accuracy, I have the following points to raise.

Why are you shooting at f2.8 and 1/2000. Clearly more depth of field would help. trade f stops for shutter speed.

are you tripod mounted? if not shooting at an angle could give you a problem with vertical shake and focusing on the wrong point.

ALso note that depth of focus is not linear, 1/3 in front, 2/3 behind focus.

how is the focus indicator shown, diid you draw it in? I note it is a different shape for the three shots

is focusing continuous or single. Have you tried manual focus also?
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!
gear, ie, 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
Architecture Lady Luck zombieCat Photo Critique 2 03-19-2010 07:53 AM
Luck would have it :) boodiespost General Talk 2 12-11-2009 04:33 PM
Luck mickeymon Monthly Photo Contests 0 05-31-2009 01:56 PM
Wish me luck! rmtagg General Talk 26 10-24-2008 07:51 PM
Good luck JCSullivan General Talk 0 09-09-2006 05:18 AM



All times are GMT -7. The time now is 08:18 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