Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Another decentered lens, another delayed review ...
#31
Just unpacked the replacement copy of the Tokina 16-28. I'll check for centering immediately.



Also: will get a second sample of the Sigma 85/1.4 next week and see if it behaves like the first one.



-- Markus
Editor
opticallimits.com

#32
[quote name='IanCD' timestamp='1298742939' post='6381']

With Nikon at the other end of your QC scale, maybe the 12-24 looks an (expensive) better bet?

[/quote]



Well, umm... I've used two Nikon 12-24s so far. Neither exhibited really good centering quality.
#33
[quote name='BG_Home' timestamp='1298845139' post='6390']

Well, umm... I've used two Nikon 12-24s so far. Neither exhibited really good centering quality.

[/quote]



Similar experience here with the Nikkor 17-55/2.8.



-- Markus
Editor
opticallimits.com

#34
[quote name='mst' timestamp='1298837855' post='6389']

Just unpacked the replacement copy of the Tokina 16-28. I'll check for centering immediately.

[/quote]



Better, but still not good. Good enough for a lab test (where I can work around the issue somewhat), however I won't do any field tests with it.



-- Markus
Editor
opticallimits.com

#35
[quote name='mst' timestamp='1298845583' post='6391']

Similar experience here with the Nikkor 17-55/2.8.



-- Markus

[/quote]



Well, to sound a little more positive, my unsatisfactory N70-200 VR2 is my first bad Nikkor



Between my wife and myself we've had 12 good ones over the years



That's it - It's the 13th That's the reason!!
#36
I was not aware of the second effect - interesting. With global loss of contrast you mean that the whole image frame is affected evenly? If so, it is really hard to check because one would need a second lens to compare the contrast levels. Low contrast alone could just be a normal "feature" of the lens.





[quote name='Klaus' timestamp='1298732900' post='6380']

That's one potential effect - one or more elements are more or less centered (the center is where it should be) but tilted.

The other one is a more a global loss of contrast caused by an off-center (shifted) element and that's harder to check in shops.

[/quote]
#37
[quote name='BG_Home' timestamp='1298845139' post='6390']

Well, umm... I've used two Nikon 12-24s so far. Neither exhibited really good centering quality.

[/quote]



While searching for the "perfect" walk-around lens three years ago I had to test three exemplars of the 16-85 VR. Each of them had a different weakness. At the end I kept the lens which mostly suited the anticipated usage (more at the wide end than at the tele end).



At the moment I mainly use a Sony A850. Here, my walk-around lens is a Tamron 28-75. My exemplar has clearly a tilted focus plane at the tele end. However, I am tired of the lens selection game and accept it like it is for now.
#38
[quote name='mst' timestamp='1298845583' post='6391']

Similar experience here with the Nikkor 17-55/2.8.



[/quote]



Interesting. So I'm not alone on that one, too. Does yours focus properly (front/backfocus)?
#39
[quote name='BG_Home' timestamp='1298930523' post='6406']

Interesting. So I'm not alone on that one, too. Does yours focus properly (front/backfocus)?

[/quote]



Sorry, Basil, but I currently don't own one.



-- Markus
Editor
opticallimits.com

#40
[quote name='mst' timestamp='1298930676' post='6407']

Sorry, Basil, but I currently don't own one.

[/quote]



Alright, no problem.
  


Forum Jump:


Users browsing this thread:
1 Guest(s)