Nikon 300 f/4 problem

[Infinite_Day]

I bought a used "D" condition 300mm f/4 lens from Adorama. It's cosmetically flawless but I cannot seem to get a good photo from it. Every pic seems to be coming out a bit blurry. I've had a Kenko Pro 300 1.4 TC on it but even without it on the photos look the same. I've tried stopping it all they way up to f/13, 1/2000 shutter speeds, increasing the sharpness in the camera (D7000), adjusting the fine focus adjustment both up and down through the range and it seems like the photos just aren't even close to sharp. I've hand held, shot with the lens on tripod, etc. Has anybody ever gotten a bad copy of this lens? I'm thinking of seeing if I can return it. I'm really disappointed because I mulled over buying this lens for a long time and my crappy 70-300mm Quantaray takes better photos. Any suggestions?

 

[Tomasko]

If photos come out blurry even when shooting on a tripod, there must be something wrong with the lens... I'd personally return it.
Maybe try to post some example pictures, so we can see the problem?

 

[joealcantar]

Return it and don't wait on getting a Return Authorization #. Ask them for another lens in a little better condition for your troubles.
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Shoot well, Joe

 

[chaosrealm93]

return it

 

[Infinite_Day]

Return it and don't wait on getting a Return Authorization #. Ask them for another lens in a little better condition for your troubles.
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Shoot well, Joe

The only better condition is new. "D" is Adorama's highest rating for used equipment. I actually think I may have figured out the issue. I think I bought a bad UV filter. I read some good reviews about Best Buy's Rocketfish UV multicoated filters so I picked one up because they were the only option beside ordering one. I actually have one on the 18-105 kit lens and have had no problems. I took the filter off after the original post and I think that the pics are looking much better. I may take some test shots and upload them but I'm currently out of town on a work trip and don't have time to mess with it.

 

[Tomasko]

Oh, you didn't mention you use an UV filter on it Filter is always the first thing to check when you're experiencing blurry images. Especially if you've bought one of those cheap ones...

 

[Overread]

When you next get the chance run a controlled test:

1) Put the lens bare on the camera, no filters, teleconverters or additional attachments.

2) Put the camera lens combo onto a stable tripod/surface and turn IS off (whilst most modern IS systems can detect stability and not needing to be engaged themselves, its not perfect and will take time to power up and down - so its best to leave it off)

3) Aim the camera at a test subject, a 45degree angle to a flat plane is ideal as you can then minimise focusing errors as a part of softness *since at an angle you'll get a clear "in focus" band at least upon one part of the subject even with a minor focusing error.

4) Test at varying apertures - typically things sharpen up as you go from wide open to f8 and then will start to soften - remaining usable up to around f13 on crop sensor and f18 on fullframe.

5) Use a remote/timer and mirror lock up (custom function - check manual) to minimise the amount of shake from tripping the shutter.

The above gives you a stable, sure setup that minimises the potential for user error in the process and gives you the bare results from the lens and camera to work from.

Note even if results are not optimally sharp this does not mean there is a fault with the lens itself; instead its likely a case of compatibility issues as a result of manufacture tolerances (ergo - neither camera nor lens is "faulty" but is just at opposite ends of the calibration scale, resulting in sub-par performance when the specific units are put together). Correction for this is easily possible, however requires sending camera and lens away (and unless you add all your lenses to the package you need to make sure on the repair slip and on a note in the package, that the camera is not to be adjusted).

 

[Infinite_Day]

Thanks for the tips Overread. I will try that this evening if the weather improves or if I can find a place in this hotel to work. The 300mm f/4 AF-S doesn't have built-in image stabilization so I don't have to worry about that. A remote release is going to be my next purchase. I guess I'll have to see if I can return the filter and order a B&W or Hoya. Hate to be out $45 so I hope they will take it back. I'm going to mess around with the lens a bit longer and if the images are looking good I'll keep it. I was just peeved because it's supposed to be one of Nikon's sharpest lenses and I couldn't get a decent image out of it!