# trying to understand hyperfocal distance



## EandSphotography (Mar 15, 2010)

Hi everyone. I'm trying to understand hyperfocal distance and how to use it correctly. I'm most interested in landscape photography and from what i've read this is the best way to get those classic front to back sharp pics that you see in magazines. So this is where i need your help. I havent been outside to actually use what i've think i've learned yet, but wanted to get a headstart on your advice and when i come back in , i'll update what i've come up with. So, i'm shooting a canon 50d and we'll use a 16-35mm 2.8 lens. set at 35mm for this experiment. I'm using a website and iphone app called DOFMASTER.com if you want to follow along. 
So choosing my camera from the drop down list (50d) so that it properly calculates the crop factor into the equation i put in the focal length of 35mm. next selection is f-stop. we'll choose f-16. and then finally subject distance will be 5 feet. So what i'm wanting to do here is take a picture of a small tree that will be in focus but also have the background which goes basically out to infinity and have it in focus ( or as much as possible)

So with those selections the dof calculator comes up with this...
Subject distance=5 feet
near limit 3.65 feet
far limit 7.93 feet
total 4.28 feet (i assume this is the total depth of field at this aperture)

In front of subject = 1.35 feet (32%)
behind subject = 2.93 feet (68%)
Hyperfocal distance 13.3 feet
circle of confusion =0.019mm

now, if your on that website there is a diagram showing a picture of a man shooting some trees.  it says : 
focus at the subject distance of 5 feet and the near limit of acceptable sharpness is 3.65 feet , the total depth of field is 4.28 feet and the far limit of acceptable sharpness is 7.93 feet.

second diagram shows the same image but it is focused at the hyperfocal distance of 13.3 feet and the depth of field extends from 6.65 feet to infinity.
This is where i'm getting confused a bit.  So do i now focus at 13.3 feet past the subject that i was originally shooting at 5 feet or do i focus 13.3 feet from where i'm standing which i guess would be about 8.3 feet past the original subject??
next question is according to this diagram if i focus at the hyperfocal distance of 13.3 feet my depth of field will extend from 6.65 ft to infinity.
But originally i'm 5 feet away from the little tree. So does that mean i have to move back 1.65 feet to get the tree within the depth of field??

I hope i made this somewhat clear as to what i'm asking, but if you have time and go to that website it will be easier to see what i'm talking about. on the page it is the tab on the left that says on-line DOF calculator. There is also an iphone app that i downloaded this morning for $2 which does the same thing that i'm hoping will come in handy for use out in the field.

I know this is kinda long so i appreciate you guys taking the time to look over it and help me out.

Thanks,
Erik


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## EandSphotography (Mar 15, 2010)

ok, so i see a few people looked at this post, but no replys yet. That's ok. I was outside playing around and this is what i've come up with so far. I changed my measurements just a bit so that when i focused on the hyperfocal distance the subject (the small tree) would fall into the near part of the DOF range. 
So , i did a shot a 35mm focal range at f-18. the tree is at 9 feet. The near dof is 5.13 feet and the far is 36.6 feet . total dof = 31.5ft DOF. The hyperfocal distance on the calculator showed 11.9 feet. 

2nd shot still in same position of 9 feet away from the small tree but this time i focused on an object that i placed at 11.9 feet away. near DOF shows 5.95 feet and far DOF shows infinite on the calculator. While i can say i do see a difference between the two as far as the DOF goes, i dont believe it's "tack' sharp like it should be using this method. 
Also, i should mention in case your wondering, the distances are exact cause i set it up in my backyard and used a tapemeasure to be sure i had the exact distances.
So, what's up? how can i get that tack sharp magazine picture that you see everything sharp front to back??

help help help.

Erik


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## Hardrock (Mar 15, 2010)

Well that is a lot of info. I really haven't studied hyperfocal but according to "Understanding Exposure"  and what you probally already know the smaller the F-stop the more DOF throughout the picture. I think the problem is going smaller the f22 you lose a lot of quality. Now I really enjoy landscapes and usually stay around F8 to  F16 but My subjects are further than 5 feet. So sorry for not really answering your question and Im sure someone will eventually chime in with a great answer.


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## Hardrock (Mar 15, 2010)

EandSphotography said:


> ok, so i see a few people looked at this post, but no replys yet. That's ok. I was outside playing around and this is what i've come up with so far. I changed my measurements just a bit so that when i focused on the hyperfocal distance the subject (the small tree) would fall into the near part of the DOF range.
> So , i did a shot a 35mm focal range at f-18. the tree is at 9 feet. The near dof is 5.13 feet and the far is 36.6 feet . total dof = 31.5ft DOF. The hyperfocal distance on the calculator showed 11.9 feet.
> 
> 2nd shot still in same position of 9 feet away from the small tree but this time i focused on an object that i placed at 11.9 feet away. near DOF shows 5.95 feet and far DOF shows infinite on the calculator. While i can say i do see a difference between the two as far as the DOF goes, i dont believe it's "tack' sharp like it should be using this method.
> ...


 
Maybe the answer is stacking the photos using the sharpest f-stop.


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## EandSphotography (Mar 15, 2010)

Hi there Rock. thanks for chiming in. And yes, while i understand that the smaller f-stop will give you greater DOF, i've also read that it will cause diffraction and cause the image to appear softer in the background. So, at f8-16 , i would agree would give you the sharpest image, but i'm just not seeing it. before i just used to think it was because of the lens i was using ( a cheap tamron zoom) but now i've got a $1200 l series lens stuck on the front so i know that I'm the problem and not the lens. Now we just have to get that part corrected and i'll be good to go.

Hope i get some good answers. And yeah, i know that it was a lot of info in that first post but i wanted to be thorough.


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## Hardrock (Mar 15, 2010)

I really think your answer is photo stacking. Use the sharpest f-stop and place  the camera on a tripod. Take numerous pictures without moving the camera and exposure but change the focus every time manually . Then in photoshop combine all the photos to get a picture thay is tack sharp throughout.  If its not the answer it sounds like fun anyway. Good luck!


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## Hardrock (Mar 15, 2010)

Oh do you have an example picture in mind?


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## Overread (Mar 15, 2010)

I've never done hyperfocal focusing, but I always thought it was refering to the markers on the lens for distance rather than actual distance in the real world - though I could be totally and utterly wrong on this.

Focus stacking is an option, but its more limited in landscape since you have to remember that each shot will take time to expose and even light wind will lead to leaves and other frame content moving. If its like HDR blending a black land to a bright sky a little bit of movement is no worry as the two areas don't affect each other - but it would be a nightmare if you were shooting a woodland scene since each time you try to link the trees together you would have blur from the leaves being in different positions. 

Like I say its not an area I know well (landscape) and whilst stacking is an option I'm sure the hyperfocal focusing can work. You might want to creep down and try f13 or f10 just as f16 is right on the line where diffraction tends to start to cause the most trouble (it varies from lens to lens and camera body to camera body)


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## KmH (Mar 15, 2010)

EandSphotography said:


> Hi everyone. I'm trying to understand hyperfocal distance and how to use it correctly. I'm most interested in landscape photography and from what i've read this is the best way to get those classic front to back sharp pics that you see in magazines. So this is where i need your help. I havent been outside to actually use what i've think i've learned yet, but wanted to get a headstart on your advice and when i come back in , i'll update what i've come up with. So, i'm shooting a canon 50d and we'll use a 16-35mm 2.8 lens. set at 35mm for this experiment. I'm using a website and iphone app called DOFMASTER.com if you want to follow along.
> So choosing my camera from the drop down list (50d) so that it properly calculates the crop factor into the equation i put in the focal length of 35mm. next selection is f-stop. we'll choose f-16. and then finally subject distance will be 5 feet. So what i'm wanting to do here is take a picture of a small tree that will be in focus but also have the background which goes basically out to infinity and have it in focus ( or as much as possible)
> 
> So with those selections the dof calculator comes up with this...
> ...


You need to focus on something at 13.3 feet to have the front of the DOF be at 6.65 ft.

If you move the camera all the numbers change. All measurements are made to the image sensor plane, not the front of the lens. Your camera should have an icon on it showing the image sensor plane.


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## Mike_E (Mar 15, 2010)

Try this..
Understanding the Hyperfocal Distance


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## ghache (Mar 15, 2010)

When i shoot landscape, i mostly use an aperture or F8 to F16 and focus on the one third of the image. 

if the sky is taking 1/3 and the foreground 2/3 i try to focus on the horizon, then i use an F stop that will make my foreground look as sharp as possible

lets say your using a wide angle lens at 13mm and F11, any thing farther than 2.43 ft will be sharp, even some object close to in you placed in the foreground. This is why i like to use wide angle lens for landscape, once your using a slower fstop, the distance where object become sharper go shorter and shorter!

all depends on the focal lenght you are using and the F stop and where do you focus.
if you take the shot and the the main subjet of the photo is rock in the foreground, have the forground take 2/3 of your picture and focus on the rock. if you did set your F stop correcly, the background should be relativly sharp/in focus


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## matfoster (Mar 15, 2010)

ascertaining accurate distances like 6.25 feet in a real world situation (?) ..easier just to bracket a few shots (aperture priority) F8, F11, F16.


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## Plato (Mar 15, 2010)

Don't get wrapped up in details.  Consider...

1. Focus on something, anything, and take a picture.  In theory, only that object, nothing closer and nothing further, will be in focus.  In reality, the human eye can tolerate some error and the "in focus" distance will range from a distance a bit closer than the focus point to a distance a bit further than the focus point.

2. Now, move the focus point so that the "further" distance is equal to infinity.  Voila!  You have focused on the hyperfocal distance!

It's somewhat easy to find the hyperfocal distance with many non-zoom lenses as the near/far points are marked on the lens.  I've seen only one zoom with the markings.


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## Proteus617 (Mar 15, 2010)

EandSphotography-As a rangefinder user I shoot hyperfocal all the time.  A few quick points:

-This stuff is only confusing because you are probably using a lens without a DOF scale on the barrel.  If you had one, you would set your aperture, and focus your lens so that your infinity mark lined up with your chosen aperture.  Your nearest point of acceptable focus would now be lined up at your other aperture mark and your hyperfocal distance would be right on top of the barrel staring you in the face.  No calculators or math involved.
-Wikipedia has a very good page on DOF and hyperfocal distance.  The math is not that hard.
-Not to argue with St. Ansel and the F64 school, but your really don't need to shoot your landscapes all the way stopped down and hyperfocal.  You will probably find your lens has a sweet spot at an aperture a few stops back.  Check out the math and you will find this still gives you a ridiculously large DOF was a distant object is your subject.


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## Dwig (Mar 15, 2010)

EandSphotography said:


> ...
> But originally i'm 5 feet away from the little tree...



So why do you think that using, or even knowing, the hyperfocal distance for your chosen f/stop is important?

Hyperfocal distance calculation is a special case DOF calculation. All it is is the focusing distance that places the far limit of the DOF, for that given lens camera and f/stop, at infinity. Its of no use unless you want to keep infinity in focus and don't want to "waste" any DOF on distances beyond infinity. For situations where all of the important subject matter is distinctly closer than infinity it is totally useless.

Most hyperfocal distance calculators approach the topic bass ackwards. In fact all formulas and methods of calculation that I've seen posted on any of the forums that I read in the past several years have been backwards. They work on paper, but have no utility in the field. The proper approach is:

1. Decide the proper framing and composition of your picture. If maintaining reasonably sharpness at infinity is important continue with hyperfocal calculations; if not use a more generaly DOF calculation.
2. Measure the distance to the closest object that you need to have reasonably sharp.
3. Consult a detailed hyperfocal distance chart or use a proper hyperfocal calculator to determine what f/stop is necessary to hold focus from your closest subject to infinity.
4. Consult the same chart or calculator to determine the hyperfocal distance for that f/stop.
5. Focus the lens at the hyperfocal distance and set the f/stop calculated in #3.
6. Meter to determine the proper shutter speed for that f/stop and make the exposure.

You'll notice that the hyperfocal distance and the f/stop are answers and not predetermined input data. Where most descriptions of the process go wrong is to start with a pre-determined f/stop and listing the near limit distance as one of the calculated answers. The formulas can be used this way, but in the real world that approach is only valid for certain types of street shooting where you treat your camera like a fixed focus box camera an use one focus setting for all pictures.


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## mdtusz (Mar 15, 2010)

Use your depth of field preview...


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## Hamtastic (Mar 16, 2010)

DOF is controlled by 3 things with most cameras.

increases DOF:  smaller aperture, shorter focal length, farther focusing distance

decreases DOF:  larger aperture, longer focal length, closer focusing distance

At close focusing distances the amount of DOF is closer to even in front and in back of the focus point.  As focusing distance increases so does the DOF, but the part of the DOF behind the focus point increases much faster than the part of the DOF in front of the focus point.  For most normal and wide angle lenses (shorter focal lengths) set to middle apertures the DOF behind the focus point becomes effectively infinite (everything is as in focus as the lens will allow) at focusing distances of less than 30'.  

The hyperfocal distance is the focusing distance where DOF becomes infinite behind the focus point.  It is the maximum possible DOF for the particular aperture and focal length.  If you continue to increase focusing distance you are actually decreasing DOF in front of the subject, and you are not adding anything on the back because infinity is the limit.


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## davebmck (Mar 16, 2010)

As you already know, the hyperfocal distance is a function of your focal length and f stop.  You usually know what f stop you want, so set that, zoom to compose your shot and read your focal length.  Put those two numbers into a hyperfocal chart or calculator (I use an Iphone app) and you will get the hyperfocal distance.  Focus at that approximate distance and you will get the maximum DOF possible with that aperture and focal length, which is from 1/2 the hyperfocal distance to infinity.

If you want to maximize your sharpness, even in good light, you need to:
1. Mount your camera on a sturdy tripod
2. Lock up the mirror
3. Use a shutter release or a 2 second delay on the manual shutter.


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