Infinite Depth of field

[kabalman]

I have seen various threads about hyperfocal distances and there seem to be some conflicting information, and I'm confused. Hopefully you guys can help me here.

I have a Nikon DSLR with a crop sensor and I would like to shoot landscapes and get very good depth of field. I therefore think that I would have to figure out the hyperfocal length for the aperture I would be using. For example, if I want to use F/11, it is about 5 feet. Should I focus on something at 5 feet and recompose after locking focus, or should I focus at twice the hyperfocal length i.e. 10 feet? Please help.

 

[arclight]

Focus about one third of the way into the picture.

 

[Suvv]

I have seen various threads about hyperfocal distances and there seem to be some conflicting information, and I'm confused. Hopefully you guys can help me here.

I have a Nikon DSLR with a crop sensor and I would like to shoot landscapes and get very good depth of field. I therefore think that I would have to figure out the hyperfocal length for the aperture I would be using. For example, if I want to use F/11, it is about 5 feet. Should I focus on something at 5 feet and recompose after locking focus, or should I focus at twice the hyperfocal length i.e. 10 feet? Please help.

Focus at the hyperfocal distance.
Everything at half the hyperfocal distance to infinity will be in focus.

Having said that

The hyperfocal calcs. use a lot of assumptions about what is acceptable as "in focus", how large you will print, what the viewing distance will be, how good the viewers eyes are etc. they then use a formula which comes out with something like 4.76 feet as the hyperfocal distance and 2.38 feet as the point of nearest focus as though something at 2.38 feet is in focus but something at 2.37 feet is out of focus.

 

[marky.b]

this is a subject that completely baffles me
how do you know how far away 5 feet is without measuring it
sorry if i sound dumb

 

[joxby]

this is a subject that completely baffles me
how do you know how far away 5 feet is without measuring it
sorry if i sound dumb

If you can't estimate it, you'll have to measure it won't you..

Lie down and put a brick by your head, that'll be near enough, and that's without even knowing how tall you are.
Another positive is you will have a personal "style", recognisable by the red house brick in the foreground of every scape you shoot......no need for watermarks.

 

[Alastair]

this is a subject that completely baffles me
how do you know how far away 5 feet is without measuring it
sorry if i sound dumb

How tall are you? either lie down on the ground or imagine yourself lying down. How far away is the tv, bookcase or the blue sock under your bed?

Judging distances takes practice (and sometimes imagination), but think around the problem and practice.

 

[AJQS]

Or if you have a scale marked on the lens, use that! Manual mofcus lenses are your friend if you're going to use hyperfocal focussing, they have a scale properly designed for the purpose! (Although it'll be designed for fullframe, you can go one stop down from what it says on the lens with APSC)

 

[woof woof]

If you're looking at a hyperfocal table and it says something like - "f11, 5ft, Near = 2.4 - Far = Infinity" then you measure or guess 5ft and hope everything from half that to infinity will be acceptable.

An alternative to consider is to set your aperture based on the resolution you want. It's pretty easy and you don't need to study DoF tables...

http://www.northlight-images.co.uk/article_pages/hyperfocal_distance.html

and...

http://www.trenholm.org/hmmerk/DOFR.html

For the smallest item you want to be captured acceptably sharp = the focal length divided by aperture, and to get the aperture it's focal length / object size = aperture. So for a 5mm object at 50mm... 50mm (focal length) / 5mm (object) = f10, another example... 3mm object at 24mm focal length = f8.

If you're not happy with the results use the next smallest aperture.