How do you focus for landscape shots?

[daws]

On my 5D, manual focus: viewfinder for composition and rough focus, then angle finder at full magnification for fine focus (accompanied by jaw clenching, teeth gritting, squinting and general muttering).

[Ray]

The LCD doesn't have a diopter adjustment.

On the other hand, the spectacles you might need to view the LCD screen are also useful for all the other adjustments and controls on the camera body, as well as being useful for reviewing the image you've just shot.

Since I'm one of those who needs specatcles for normal reading distances, I find I'm continually putting on, and taking off, my glasses when out shooting.

I think that generally, manual focussing is only justified when using wide apertures with a lens that you know is not particularly accurate with its autofocussing. Most (or a good many) landscape shots are probably taken with a view to achieving maximum DoF without too much compromise of resolution. In such circumstances, I see little point in trying to be ultra-accurate by using manual focussing.

Jonathan Wienke's point about the recomposing technique throwing off the original foussing to some small degree, when using a single, central focussing square in the viewfinder, is a problem only when using wide apertures at close distances.

[OldRoy]

A small point which is slightly off topic, but not too much I hope. I have a D200 and I'm constantly annoyed by the 3-position focus mode selector switch adjacent to the lens mount. This is horribly sloppy and actually seems to have positions where it has been moved but not quite activating the selection - which for me is usually between the "M" and "S" modes. It's always been this way and I have no idea whether it's a design fault or a one-off with my own example. I waste quite a bit of time rechecking it.

[Thalaxis]

I use a ground glass and a loupe. With dSLR's I use manual focus, with help from live view. I've found that the focus and recompose method is less convenient as well as less precise, so I prefer manual focus for the most part. I do that for macros as well.

[jerrygrasso96]

My eyes are not what they used to be. MR suggested that I use autofocus rather than manual focus. But if you want maximum front to back clarity, you'd set a small aperture and would you set your lense to infinity, or focus on something at the minimum hyperfocus point? What if you are using a medium zoom, like a 70-200mm, would you do anything different? What has anybody found with a Canon Mark III is the smallest aperture you'd risk using to avoid diffraction? F/22?

[Thalaxis]

My eyes are not what they used to be. MR suggested that I use autofocus rather than manual focus. But if you want maximum front to back clarity, you'd set a small aperture and would you set your lense to infinity, or focus on something at the minimum hyperfocus point? What if you are using a medium zoom, like a 70-200mm, would you do anything different? What has anybody found with a Canon Mark III is the smallest aperture you'd risk using to avoid diffraction? F/22?

If you focus at infinity, the foreground will be soft. If you focus at the minimum hyperfocal distance, the foreground will be (reasonably) sharp.

The only thing that differs based on the lens is how wide a field you can get with hyperfocus. If you have a camera with live view, use that and magnify the image to check your focus; it's like having a built-in loupe. You'll never get it perfectly sharp, of course; for that you need tilts and such, so you have to pick and choose where you're going to compromise on sharpness. In most cases with landscape images, if the foreground is soft, the image will look out of focus, but if the foreground is sharp, the image will look sharp even if the stuff in the background is soft, as long as it's not egregious.

[Plekto]

I've found, though, that it is better to focus on something not expected or atypical if you can in the mid-distance(say a tree or a rock or something so that there's a bit of bokeh (eeensy bit) in the distance.   That way, it looks a bit more like a painting and a little less like a sterile print.  It also hides some of the pixelation/makes it look a bit more film-like.  As you can imagine the AF hates landscapes like this, so I turn it off almost all of the time.

If your eyes are getting older, a quick trick do do this is to set it to infinity and ever so slightly nudge the focusing ring a millimeter or two back to soften the extreme distance.  I kind of wish there was some sort of manual stop/peg that the focusing ring could be set to not go past(so it would always be a tiny bit off from infinity), but I don't know of any gizmo like this.

[ErikKaffehr]

Hi,

Depth of fields scales are calculated for a pretty tolerant level of unsharpness. I would recommend using marking for f/8 when stopping down to f/16.

Erik

I can't remember the last time I set focus by focusing on a particular element within a scene; I simply don't do it. Typically I'll decide on the nearest and furthest points that I want to be in focus and use the comprehensive scale on my lenses to set focus accordingly.

The problem with most autofocus and zoom autofocus lenses is that they are extremely short throw barrels with little or no DOF information and are therefore pretty much crap for landscape work.

[ErikKaffehr]

Hi,

There is no magick, depth of field is limited. I'd suggest that we can use autofocus on something far away but not infinity. Regarding diffraction you loose sharpness once you go beyond f/16. There is loss of sharpness beyond f/11 on any lens that deserves to be put on a DSLR but I would suggest that f/16 is still OK in most cases.

I would also suggest that it is better to have either foreground or background sharp then evrything soft.

Best regards
Erik

My eyes are not what they used to be. MR suggested that I use autofocus rather than manual focus. But if you want maximum front to back clarity, you'd set a small aperture and would you set your lense to infinity, or focus on something at the minimum hyperfocus point? What if you are using a medium zoom, like a 70-200mm, would you do anything different? What has anybody found with a Canon Mark III is the smallest aperture you'd risk using to avoid diffraction? F/22?

[ErikKaffehr]

Hi,

Diffraction is just a law of physics. The reason that diffraction matters less with larger formats is AFAIK twofold:

1) Enlargement is less if same printing size is assumed
2) By and large large format lenses are less sharp than smaller format lenses

Erik

I always allow 2 stops.

Diffraction is far less of a problem when using larger formats.

[Marlyn]

Personally.  I either

1.  Manually focus using live view and 10x zoom,  including DoF preview.  I use this a lot on the tilt/shift lenses, which are my main landscape lens.   The focus confirmation helps here also.

2.  Focus off something in the scence at appropriate distance (Either autofocus, or manual using focus confirmation), then check the scale on lens just to make sure of DoF


Regarding Diffraction, it is a strange beast.  Been doing some research on this latley.

On my 1dsmkIII, anything beyond f10, will suffer from diffraction limiting the effective resolution.   This is a law of the physics of light pretty much.
      In my research on the net and some testing, I concluded that when the size of the airy disk gets bigger than twice the size of a pixel, (twice is an accepted value, on a bayer array), then detail will be lost due to diffraction.

This has nothing to do with print sizes, circles of confusion etc,  I'm just refering to CAPTURE resolution and amount of detail captured in a shot.


When using the scale on the lens to set the DoF (effectivley, focusing a the Hyperfocal distance), it is a good idea to use an appeture a stop lower than what you are shooting, as these scales are overly optimistic in what is 'acceptably sharp'.

For the mathamatically inclined,  A good site to play with the number is Cambridge Color.  http://www.cambridgeincolour.com/tutorials...-calculator.htm
Try changing the setting from 'manufacturers standard'  to 20/20 Vision.  The distances change considerably !.


Mark.

[bretedge]

I use several techniques depending on the situation.  I always try to use autofocus first.  I'll set the focus point where it needs to be, then press the shutter halfway to gain focus.  If whatever element I need in focus doesn't happen to fall on an autofocus point I'll either resort to manual focus and Live View or, with the camera on my tripod, tip the tripod to angle such that the focus point is on the right element, press the shutter half way to achieve focus, reset the tripod and then make the exposure.  It usually works pretty well.