Using Hyperfocal in The Field

[dave.englund]

I've been getting to know hyperfocal focusing in the last couple of months. I

have a couple of practical questions I hope y'all can help me with.

 

(1)Each lens seems to have an f/stop (or f/stop range) in which it performs

best. Should you try to stick within that range or go with the strict hyperocal

settings?

 

For example, lets say the chart says use f/22 and a hyperfocal distance of 7

feet (meaning everything from 3.5 feet going toward infinity will have an

apparent in-focus quality). But if my Tamron wide angle lens functions best at

between f/11 and f/16, should I try to adjust my focus point for a hyperfocal

range that fits these f/stops? Obviously, I would be giving up more of the

foreground element then.

 

If I don't have a chart handy and want to use the old method of small f/stop

and focusing 1/3 into the scene...

 

(2)In terms of the old rule of focusing 1/3 of the way into the scene, do you

try to do that based on what you see with your eyes off camera, or based on

your composition within the camera's view finder? For example, my Canon 30D has

a 9 point focusing matrix. If I assign the top point #1, and go clockwise, then

#4 point would appear to be about 1/3 up from the bottom of the view finder.

So, would it be a sound practice to use this specific focusing point as a way

of focusing 1/3 into the scene? Or, do you look up from your camera and

think, "Well, that bolder out there seems about 1/3 of the way from here to

infinity, so I'll focus on that."

 

Thanks. Sorry if these are silly questions. Please bear with me I'm still

learning;-)

[ellis_vener_photography]

not silly at all. The truth is, from a photographic point of view rathert than a theoerectical or technology point of view, you are best to focus on theelement of the photogrpah that is most important to that particular photogrpah and then stop down to the optimal aperture for that specific lens. How will you know what the optimal aperture for a specific lens and camera combination? You will only know from empirical testing of that specific lens and camera combination. This is especially true with DSLRs.

 

Beyond that, if you are just looking for deeper or shallower depth of focus without regard to ultimate resolution then by all means use hyperfocal technique.

[younes]

My use of hyperfocal distances has been more or less mitigated. I have tried several charts available on the net as well as from some magazines, but on my sigma 10-20, they don't seem to apply for some reason. I have done a little experiment focusing at .24, .5, .75, 1m and infinity at f16 and f22 using focal lengths of 10, 12, 16 and 20 mm (the crop factor is 1.5x on my nikon). Invariably, the best end to end sharpness happened when I focused at 1m (3f), independently of f-stop or focal length...While it's a bit of pain to do, I would suggest you try something similar with your camera/lens combo.

[ronald_moravec1]

Ellis is correct.

 

When faced with needing a deep range of focus, I focus and the most important point and check the scale to make sure near and far are inside.

 

If there is no most important, but I need a range, I use the scale.

 

Infinity may not be part of establishing the proper setting.

[frank uhlig]

If your "field" = landscape contains an infinite point, such as a tree way off or a horizon, then by all means focus on that (= infinity) or it will be blurry, not well resolved and it will appear rather mushy in an enlargement.

 

Then close down to optimal aperture, which may often be at f/5.6 already, set on tripod and shoot. You will see a bit more mush close up, but it will be much more pleasing to have infinity in focus.

 

google 'harold merklinger` and spend the time to read and experiment with his method. Do compare to hyperfocal focusing and pick whatever method pleases your more.

 

You will have nicer pics WITHOUT any of that hyperfocal nonsense with landscapes, I think.

 

Only use hypefocal only when you have a subject that does not include infinity, such as a room, desk, ... or when you want to use selective focusing on the eyes in a portrait.

 

Good luck, but i think you have learnt what hurts you in the end. Now become flexible and relearn to produce a better landscape product ...

 

And more good luck!

[allison_reese2]

Frank is correct according to, http://jimdoty.com/Tips/Depth_of_Field/More_DOF/dof_merklinger/dof_merklinger.html

[kuryan_thomas]

Using the Merklinger technique has really been liberating to me when I do landscape

photography. Used carefully, it makes all the difference between endless futzing with

hyperfocal charts - or spending the time to get better compositions.

 

The problem occurs when the Merklinger technique calls for an aperture smaller than the

diffraction limit of your system. In that case, go with Ellis's technique.

[dave.englund]

Y'all do know how to mess with a guys brain! I just finished all four of Merklinger's articles. Ouch! Hey, I'm a guy that broke into a cold sweat when I had to do word problems in grade school. But, here's what I'm taking away from the read (from the second to the last paragraph in the last article - I coulda saved myself some pain):<br /><br />

 

"The most effective way to maximize the depth of field is often to stop the lens down to the size of the smallest detail to be recorded in the image. Then focus at infinity and shoot."<br /><br />

 

"If it is not reasonable (by virtue of the fine detail desired) to stop down that far, focus half-way through the field and stop down as far as you can."<br /><br />

 

Okay, now I do have a little confession to make. I have done some infinity focusing research of my own. Not that I understand Harold's math (I really got lost when he started talking about the thumb method;-) Rather, some time back I went out with my 30D and Tamron 17-50mm and did some shooting with the infinity focusing method across a number of f/stops. You can see my write-up of this little experiment in <a href="http://luminous-landscape.com/forum/index.php?s=d8aee97ee0ac7eaaa99bad5ba4c54907&showtopic=15539&hl=hyperfocal&st=20#"><u>this post</u></a> over at Luminous Landscape. It was clear to me then that infinity focus was the way to go for most of the field of view. I just wasn't seeing what I really wanted when I really wanted objects very close to be very sharp. So, I've been leery about fully adopting the theory. But, after reading Harold's articles I intend to give his second method a good try as well. Thanks all. It's been a good and valuable discussion.

[daniel_smith6]

Buy a 4x5 or larger view camera and learn to use it. It will help a lot in understanding what can be done.

[dave.englund]

To follow up on the discussion since my original post of June 4, I have been wavering between using Hyperfocal distance or Infinity focusing for landscapes, and it wasn't until I got out with the camera and lens this last weekend and shot at all major focal lengths over a spectrum of f/stops with both focusing techniques that I finally identified which technique works best for my Tamron 17-50mm lens. Turns out it depends on the focal length I'm using at the time. Anyway, up to now I've had to shoot tons of images using both techniques to make sure I got a good one. And, given the data I obtained this weekend, it turns out that also was hit and miss at best.

 

For example, over the course of my recent trip to Yellowstone I would typically get setup for a shot, set my lens to manual AF and focus at infinity, and then take several exposures (-1.5, -1, 0, +1, +1.5) at each f/stop (22, 20, 16, and 13). Then, I would focus 1/3 or midway into the field of view, and do the same thing again. Finally, I also shot several exposures using Canon's A-DEP feature.

 

Somewhere over the course of all those images I usually got an acceptable one. But again, it turns out it was hit and miss at best, used up memory cards like nobody's business, and produced a ton of post-processing work in assessing images. Now, having finally completed the research I can report the following for the Tamron 17-50mm f/2.8 lens:

 

@17mm - Infinity focus is best - Acceptable range is f/5.6 - 13. Best at f/8

 

@24mm - Hyperfocal and/or Mid-focus is best - Acceptable range is f/8 - 16. Best at f/13 * Infinity focus is also acceptable, but not as sharp, f/8-16. Best at f/13.

 

@35mm - Hyperfocal and/or Mid-focus is best - Acceptable range is f/13 - 20. Best at f/16. * Infinity focus is also acceptable, but not as sharp, f/16 - 22. Best at f/20.

 

@50mm - Hyperfocal and/or Mid-focus is best - Acceptable range is f/13 - 20. Best at f/16. (but it's obvious you're not going to get crisp foregrounds here)

 

So, as you can see, when I shot landscapes at 17mm and used a range of f/13 to f/22, I was only *approaching* good DOF when I got to the last f/stop (f/13), and I missed the best f/stop of f/8 altogether. Fortunately, sometimes the A-DEP function would select a stop closer to f/8. However, the problem with the A-DEP function, as I see it, is that you can never know quite where the actual focus point is. So again, it's hit and miss. Obviously, this data only applies to the Tamron 17-50mm f/28 lens. At some point I will repeat the same experiment with my Canon 70-200 f/4L lens. My assumption seems to have had some basis, that each lens has its own set of "sweet spots" in terms of focal lengths and f/stops that provide the best DOF, and it turns out this is also dependent on the method of focusing used.