Damned Annoying D7000 Focus. Ideas?

Tybrad

Hey all,
I believe that I have the oh-so-annoying D7000 back focusing problem. I have poked around online and have done what I can as far as I know. Even with the AF fine tune, no resolution- in fact, it makes little difference, even maxed at +/- 20.

It seems to be worse on my Tamron 17-50/2.8, but it is there (by a tilted webpage test) on my Nikkor 80-200/4-5.6 VR. I have reset the camera with the two green dot buttons several times- to no avail.

Does anyone have an idea that I've not mentioned here (other than a costly out-of-warranty trip to Nikon)?

Thanks!
Tyler

DsrtVW

SOunds like a messed up AF Module either Nikon Repair for an estimate or an Authorized repair shop
Repair shops
Sometimes it is all you can do to get a proper answer. I am lucky to have a shop in the area where I live so I can go there directly. I have had good results from Nikon Factory service also in El Segundo CA

ziggy53

It's vital to properly conduct autofocus tests in order to draw conclusions from the tests.

Using a computer monitor, and a tilted monitor at that, is a poor choice as a target. Computer moniotors have a "refresh" cycle which looks like "flicker" to an AF module and AF system, and it can cause all manner of results.

When I test a new lens I often choose a few different subjects for comparison:

1) A brick wall, shot straight on and squared with, using a tripod. This is a pretty good test for front-focus, back-focus, field curvature and vignetting issues. If a camera/lens combination does not focus accurately in this test, something needs to be serviced. Make sure to test at least twice MFD from the wall. Make sure to use AF-S/Single-shot mode and a single focus point for this test.

2) A fence line or similar, shot at an angle to the subject. Put a singular strong-contrast target on the top of the middle post and use a single focus point in the camera to focus against the target. This shows focus accuracy and/or how easily distracting for/aft objects influence AF accuracy (compared to the above wall shot). It also shows bokeh tendencies at different aperture settings.

3) A focus target/chart like in the following:

http://regex.info/blog/photo-tech/focus-chart

I do recommend testing these charts at twice minimum focus distance or greater. Most lenses, especially most zoom lenses, do not do their best at MFD. True macro lenses are the major exception.

4) A US stop sign, or similar very high contrast signage, both centered and off center and to the side and/or corner. This can show chromatic errors and off-axis errors.

5) A spectral highlight at night. (Point source ideally, but a street light at some distance will do.) Try to avoid "blooming" of the source but allow some white clipping. This shows internal reflections and dispersion problems. Again, test both in the center and with the subject at the sides or corners.

6) Now just shoot "typical" subjects for your use of the lens(es). It's important that the lens perform correctly for your intended uses.

Feel free to use JPGs and just give image links or directory links, but any significant issues and comparisons you may want to add inline to a post describing particular issues. These may be crops and display 100 percent if you wish. 100 percent crops aren't really fair unless you intend to print "very" large, but it can be easier to display comparisons for examination and to demonstrate problems.

Perform all of the above in the order above to gain the best understanding of how your camera's AF system is working, then translate that knowledge to your usual shooting subject matter.

jthomas

I would also suggest using a prime lens for fine tuning focus. A zoom lens may need different amounts of adjustment at different focal lengths.

Tybrad

Thanks guys. I did the monitor test just as a quickie thing. My images have been of poor (read: not tack sharp) focus and it is REALLY frustrating given that optics have been mature since Ansel Adams addressed the point so long ago. And 'ya know what? I do not feel as though all of the testing to learn about the insufficiencies in a TOTL camera where AF systems have matured should have to be done. I do not know one Canon or Pentax owner who has had to deal with this stuff- their equipment just works. Sure, there are some missed shots but with the 7000, it's systemic as far as I can tell and research.

Arrrrggg!!

Tyler

ziggy53

Tybrad wrote: »

... I do not know one Canon or Pentax owner who has had to deal with this stuff- their equipment just works. ...

All cameras and camera systems are capable of failure, and that includes Canon, Nikon, Pentax, Sony, Hasselblad, Leica, etc., ad nauseam.

Until you properly test your camera and lenses you don't know what the problem actually is.

Carpy

jthomas wrote: »

I would also suggest using a prime lens for fine tuning focus. A zoom lens may need different amounts of adjustment at different focal lengths.

On a D7000 the auto focus fine tuning is lens specific. It has a memory for up to 10 lenses, so after you have adjusted the amount of fine tuning, the next time you fit a particular lens the amount of fine tune is automatically set (if you have previously set it into the memory).

I agree that zoom lenses may need different adjustment at different focal lengths but you have to strike a happy medium with zooms.

So far I haven't found any problems with my D7000, other than those of my own making (old bloke with dodgy hands etc.)

Good Luck

Carpy

Tpsfoto

Tybrad wrote: »

I do not know one Canon or Pentax owner who has had to deal with this stuff- their equipment just works

Tyler

I left Canon years ago when the 3 new 1d mark 3 bodies would not focus on moving objects.... I was a NY JETs team shooter and my 3 new bodies for $4000.00 each would not work....even after 3 attempts for Canon to repair....they wouldn't work correctly. .....Know what Canon said when I wanted them to take them back ....NO....now I shoot Nikon

runcougar

For $30, you can get some software that will help you fine tune:

http://michaeltapesdesign.com/focustune.html

Matthew Saville

runcougar wrote: »

For $30, you can get some software that will help you fine tune:

http://michaeltapesdesign.com/focustune.html

That is only software to go along with the $80 (?) product he also sells.

I prefer to calibrate / check my focus / sharpness by simply shooting clean test shots from a tripod, and knowing what to look for in the images.

=Matt=