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I have a Nikkor 35mm f/1.8G lens on a Nikon D7000 body. I have a theoretical understanding of hyperfocal distance. And it seems like the lenses with an clear indication of "infinite" focus point are easy to focus to infinity. But is it possible to do that with my lens?

Must my lens have an infinity (∞) sign to be able to focus on hyperfocal distance? If not, then what is the easiest/most effective way to do that with my lens?

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marked as duplicate by mattdm, MikeW, AJ Henderson, John Cavan Feb 18 at 2:58

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

2 Answers 2

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So, there's actually two separate concepts here: focusing at infinity, and the hyperfocal distance. Focused at infinity means basically what it says: a theoretical object infinitely far away would be in focus. The hyperfocal distance is the distance at which you would focus the lens in order to get the maximum a parent depth of field. This is usually closer than infinity, simply because if you go all the way out to infinity, near objects are less focused.

Your lens, as almost all modern lenses, can do both of these things. (Some specialized macro lenses are the only reason exception. Well, or else adapted lenses from other systems.) But they aren't the same thing.

Unfortunately, it's hard to identify the hyperfocal distance on a lens without a distance scale and a long throw (which means the scale has enough detail to be meaningful). Plus, hyperfocal dependent on the aperture, and the degree of blur you are willing to accept as "in focus". Most people focus a third of the way to the horizon and call that close enough. (Maybe in combination with the DoF preview or some test shots.)

These prior questions should provide you with some good background:

and if you'd like to become especially confused over the technicalities of blur, see

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So the rule of thumb is "focus a third of the way to the horizon and call that close enough" ? –  Samiron Feb 17 at 11:18
    
@Samiron, yes, that's the rule of thumb. It's not perfect, of course — such rules never are. –  mattdm Feb 17 at 22:56

The hyperfocal distance is the distance to focus on, giving a specific f-stop, that will put infinity at the furthest edge of the depth of field. It's easy to calculate (chart), the problem is setting the focus to that distance on a lens without a distance scale, which most modern lenses lack. (The good old fashioned manual focus lenses had distance scales and DOF scales on them - you might pick up an inexpensive Nikkor 50mm f/1.8 AI lens to play around with that.) You could set your f-stop, determine the hyperfocal distance with a chart or calculator, then measure or estimate an object that far away, focus on it, then recompose and shoot.

Seems rather cumbersome to me. Assuming you're shooting something like a landscape that needs a large depth of field, you could probably get good results but using a small aperture (f/16 or f/22) and focusing about 1/3 into the scene. You could try a sequence of shots starting with f/8 and all whole f-stops above that (f/11, f/16, etc.), all focused to a point 1/3 into the scene, then compare the results, and see what works for you.

Added: I should add something about diffraction. Smaller apertures (higher f-numbers) increase depth of field, but increase diffraction. Diffraction decreases resolution (makes the image blurry). The smaller the aperture the more the diffraction. So there's a tradeoff between DOF and diffraction: an increase DOF will result in an increase in diffraction. So when you need a large DOF you should understand the diffraction penalty it incurs.

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I'm not sure why you'd recommend shooting a f/22 - at that aperture, diffraction softness in the lens is going to be non-trivial. Sure, shooting at f/8 and focusing on the hyperfocal distance is more work, but you'll get better results. –  Philip Kendall Feb 17 at 8:30
    
@PhilipKendall - f/22 is going to produce noticeable diffraction but it could be worth it to get the desired DOF. Probably best for the OP to try a range of apertures on the same scene to see the diffraction/DOF tradeoff. –  obelia Feb 17 at 16:42
    
Running some numbers via DOFMaster, the hyperfocal distance for a Nikon D7000 and a 35mm lens is 7.69 m. Hence unless your horizon is less than 23 m away, you're actually reducing your depth of field by focusing one third to the horizon. For f/22, the hyperfocal distance is just 2.74 m, so even more so. –  Philip Kendall Feb 17 at 22:44
    

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