400mm f2.8 sharper when VR is off?

[steve_phillipps]

<p>I've just bought a 400 f2.8 VR and have run some tests and it's clearly a little sharper when the IS is turned off. I've put the camera/lens on a massive tripod to eliminate shake and therefore the effect of the VR. Shot the same image with and without VR and the non VR ones are always slightly sharper. Is this to be expected or could there be some alignment problem?<br />Steve</p>

 

[steve_phillipps]

<p>I did the tests with the 1.4x converter on, just tried it without the converter and they then seem pretty much identical. So is there a problem with the converter/VR combo?<br />Steve</p>

 

[mark_s8]

<p>This is normal Steve. Remember, the VR system LOOKS automatically for movement when activated. If you've got the camera fixed and have VR ON, the VR system will start doing it's thing with the first press of the shutter, and if your camera is already stable, this will result in a degradation in IQ.</p>

<p>VR ON when hand-held only. Otherwise, leave it OFF.</p>

[mark_s8]

<p>Opps Steve, you were telling us about the TC as I was sending my response. So yes, I would suspect the VR system might not be playing nice with the TC. But someone else using that setup will be more qualified to comment.</p>

[steve_phillipps]

<p>Thanks Mark,<br>

Sorry I only tried with the TC and then thought that I should do it without - should have done before I posted.<br>

I assumed that with the version II with the VR tripod mode it still makes sense to have it on as it'll smooth out any wobbles by the mirror or touching the camera.<br>

Steve</p>

 

[mccosh]

<p>Your on to it Mark. Nikon themselves state that if the camera is mounted on a tripod turn of VR otherwise the VR motor itself will cause camera shake.<br>

John</p>

[steve_phillipps]

<p>So what's "Tripod" mode all about then?<br />Steve</p>

 

[walterh]

<p>"So what's "Tripod" mode all about then?"</p>

<p>400mm plus TC perhaps on a DX sensor is LONG.How stable is the camera-TC-lens connection?<br>

Some people use "so called tripods" . <br>

I guess if you use a "real" tripod say a series 5 Gitzo you want to avoid any moving optics trying to improve your lens sitting rock solid :-)</p>

 

[andy a.]

VR on a monopod makes a huge difference for the better. If you are locked on a secure tripod, however, I can't think of why you

would want it on. On the other hand, if your head is unlocked and you are, say, panning birds in flight, there can be a fair amount of vibration in the system that the VR can help with.

[mab]

<p>Right, the "tripod" mode works well when panning on a tripod or when using an unlocked Wimberly-type head. If everything is locked down, VR is best kept off, for the reasons discussed.<br>

I've found the VR performance degrades significantly when used with a teleconverter, but it still does work a bit.</p>