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Michael Hannigan
Michael Hannigan, Engineer
Category: Electronics
Satisfied Customers: 11824
Experience:  20+ Years Experience in Field. MCSE, ICCP, CNE, Greenbelt
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How to set focus on 16-85 mm lens on Nikon D7000 please.

Customer Question

How to set focus on 16-85 mm lens on Nikon D7000 please.
Submitted: 4 years ago.
Category: Electronics
Expert:  Michael Hannigan replied 4 years ago.

Michael Hannigan : Hello. My name is Michael.
Michael Hannigan : At f/5.6 focal length will be at least 70mm
Michael Hannigan : Center sharpness with this lens should be good at all focal lengths with some diffraction toward the edges, but still very good.
Michael Hannigan : The focus ring is closest to the body.
Michael Hannigan : The sharpest focus you can achieve for the full frame with this lens is at about 24mm at f/4
Michael Hannigan : Sorry, there are some problems with the chat system at the moment. I want to make sure you received this - I am referring to the AF-S Zoom-Nikkor ED 16-85mm f/3.5-5.6G IF DX VR lens. Please make sure I am talking about the same lens.
JACUSTOMER-novadek4- :

Still none the wiser on how to adjust this lens to get it to focus properly at distances near to infinity ?

Expert:  Michael Hannigan replied 4 years ago.
Eric, the system isn't behaving well today and I aplologize. I switched out of chat to make sure I can provide you with some information. If you respond to me in this format, I will reply back right away.

I'm not sure what level of information you need in terms of focusing the lens. I'm assuming that the lens is the AF-S Zoom-Nikkor ED 16-85mm f/3.5-5.6G IF DX VR lens - if I am wrong, please correct me.

The focus ring is the closest ring to the body. If you are focusing manually, use the switch on the left side of the base of the lens. That I think you know - the maximum performance of this lens will be seen at about 24mm at f/4. The center will be a little sharper one f stop down and the the edges will be softer, but should still be very close to the sharpness of the center, especially at 24mm.

I would imagine your question is more specific than what I've told you so far - just let me know and I will do my best to address specifics.

Mike
Expert:  Michael Hannigan replied 4 years ago.
For a horizon shot you should be able to get distant focus just short of at any focal length. If you are using AF fine-tuning.

Testing for back or front focus issues with calibration charts, can be very hit and miss, due to many reasons. A precise angle of 45 degrees is needed, good overall lighting of the chart, fast shutter speed, low iso, tripod, wide open aperture and then you need to decided your focus distance and as this changes the results will change.

As you can probably tell I do not like the above method and through much research and testing I have found the most consistent test is to use a moiré test pattern. This is totally free and more details including the test pattern can be found here:

www.northlight-images.co.uk/article_pages/cameras/1ds3_af...

The test chart is displayed on your computer monitor, no fancy angles are needed and rather than relying just on one focusing method, live view is used as a comparison, giving much more accurate results.

Let me know if this helps and if you have any questions.

Mike