Stecyk wrote:
Because the hyperfocal distance is between the minimum and maximum distances, shouldn't the maximum distance be infinity? That is, if everything beyond 61.4 m is in focus, then why is there a maximum distance?

No. Because you are focusing at 55m. If you focus on something 61.4m away, THEN you get infinity focus.

redo the test, with the same focal lenght and aperture, and set your focus distance to 61.4m - it will say "30m to infinity" (give or take a little on the minimum)

-JAY- wrote:
There's one thing you're missing in what you're giving us, focal length.

You are right. Sorry. It's a 100 mm.

-JAY- wrote:
Notice you got 61.4 meters hyperfocal distance in both tests? That's because hyperfocal distance is static based on focal length and aperture. Essentially, hyperfocal distance is the CLOSEST YOU CAN FOCUS TO GET INFINITY FOCUS. That's the first focus point where it's "X - infinity" Anything closer will be "Xm to Ym" --- anything past that will be "X - infinity"

The closest I could get to your 61.4 given a 1DX and f/5.6 was 101mm focal length. Did you have 100mm in your app?

Notice you still got 61.4 regardless of what you set your focus point to.

Yes, 100 mm in the app. Yes, I noticed the 61.4 in both cases, which makes sense.

-JAY- wrote:

No. Because you are focusing at 55m. If you focus on something 61.4m away, THEN you get infinity focus.

redo the test, with the same focal lenght and aperture, and set your focus distance to 61.4m - it will say "30m to infinity" (give or take a little on the minimum)

You gave me the missing piece. It is because I was focused on the earlier distance that objects at the hyperfocal distance out out-of-focus (oof). Okay, now my understanding is coming together.

Thank you.

Darryl Varner wrote:
I was hoping to be able to give you the formula for computing hyperfocal distance, but then I realized there's no way to type a math equation in this window. Digital Camera World publishes a cheat sheet that should help you, though.

The link is

http://www.digitalcameraworld.com/2013/ … eat-sheet/

Hope this helps.

Thank you for the link to the article.

HHPhoto wrote:
The hyper focal distance, is the point (distance from camera) at which if you focus on that point (distance from camera) everything from that point and between that point and infinity will be in focus.

If you focus on anything closer to the camera than the hyper focal distance your DOF is limited to a much shorter distance that ends at a point short of infinity.  The closer to the camera you focus, the narrower the DOF.  The closer to the hyper focal distance the wider the DOF.  Once you focus on an object at or past the hyper focal distance, your DOF is at least as wide as the distance from that object to infinity (i.e. on the back focus side alone).

Please see the last diagram in the green box at:
http://www.dofmaster.com/dofjs.html

Hyper focal distance is a bit different than DOF.  However, both can be calculated by the application at the website referenced above for most camera body and lens combinations at any given f stop and (for DOF) distance from the camera.

I also keep this app on my iPhone for when I am traveling and want a quick estimate/ reminder of DOF or hyper focal distance for shooting wildlife or landscapes for specific lenses.  I sort of know in my head the general numbers for my favorite lenses, but having the reference guide in my pocket is handy.

Thank you for the link and explanation. pCAM is a great app, isn't it? Again, thanks.

Stecyk wrote:
*Example One*

Assume inputs:
- camera: Canon 1Dx
- aperture: ƒ/5.6
- focus distance 55.0 m

We learn the following:

- minimum distance in focus: 29.0 m
- maximum distance in focus: 527.1 m
- hyperfocal distance: 61.4 m

Because the hyperfocal distance is between the minimum and maximum distances, shouldn't the maximum distance be infinity? That is, if everything beyond 61.4 m is in focus, then why is there a maximum distance?


*Example Two*

Assume inputs:
- camera: Canon 1Dx
- aperture: ƒ/5.6
- focus distance 5.0 m (much closer than example one)

We learn the following:

- minimum distance in focus: 4.63 m
- maximum distance in focus: 5.43 m
- hyperfocal distance: 61.4 m

I understand that objects placed between 4.63 m and 5.43 m will appear sharp. And then, objects between 5.43 m and 61.4 m will NOT be sharp? And then beyond 61.4 m are sharp again?

---

Can someone please elaborate on my questions in Example One. In general (examples one and two), is my thinking or understanding correct?

In both cases, you have set the focus at one distance (example 1 = 55 m, example 2 = 5 m). Those are NOT set at the hyperfocal distances needed. You need to change the focus distance to the listed 61.4 m for that lens and f-stop.

HHPhoto wrote:
The hyper focal distance, is the point (distance from camera) at which if you focus on that point (distance from camera) everything from that point and between that point and infinity will be in focus.

Slight point of order. That would be incorrect. Everything from one-half the hyprefocal distance (30.7 m) to infinity will be in acceptable focus. The DOF also extends in front of the focus point. Technically, only the focus point will be in sharp focus.

Stecyk wrote:
Thanks everyone for responding. I understand now.

Theory, theory, calculations and mean while your subject gets bored and walks away.

Now, the world of the practical photographer:

You will need four things:
A fixed focal length lens.
You will need a 'real' lens, one that actual has a barrel ring unobstructed by some tiny windows that woun't let you see or access the lenses barrel. Metric, feet, fish or other are totally NOT important.
Some narrow masking tape that you can mark on.
a pen that will put a mark on the tape.

Take a length of the narrow tape and wrap it around the lens barrel so that you just go from the infinity mark to about the diameter of the focus barrel.

Now, stand where you will be when making the image. Focus on the closest point you want in focus for the image. Mark that point on the tape wrapped around the lens. Now focus on furthest point you want in focus in the image. Now look down at the lens and turn the barrel of the lens, look at the marks for the f-stop expanding out from that sharp focus mark, twist the barrel until te marks for close and far distance rest opposite a common f stop. Now set you lens on that f stop. From where you are the image will be sharp at that f stop for that lens with regards to the distance from subjects in the foreground and the background you have chosen to photograph.

If for some idiotic reason you want to know the hyper focal distance for the situation you have chosen, well lift the tape and look at the focusing ring. Keep in mind you are NOT a photographer because you are not making photography but screwing around with a focus device. This is the difference between thinking about photography and doing photography.

By the by, the first interchangeable lens for a 35mm camera was the 2.8cm Hectar made by the microscopic division of E. Leitz. If stopped down to its smallest apertures of f 25, one simply rolls the lens around to its closest focus position and the image will be in focus from beyond infinity to 17 inches from the scene you are imaging.

Stecyk wrote:
I don't understand hyperfocal distance and am hoping someone can set me straight.

Being Canadian, I tend to use metric. So, 1 m is just slightly longer than 1 yard.

http://en.wikipedia.org/wiki/Hyperfocal_distance

"In optics and photography, hyperfocal distance is a distance beyond which all objects can be brought into an "acceptable" focus."

Okay, that seems to make sense.

I am using an iOS app pCAM.

I will provide two examples and comment where I am struggling.

*Example One*

Assume inputs:
- camera: Canon 1Dx
- aperture: ƒ/5.6
- focus distance 55.0 m

We learn the following:

- minimum distance in focus: 29.0 m
- maximum distance in focus: 527.1 m
- hyperfocal distance: 61.4 m

Because the hyperfocal distance is between the minimum and maximum distances, shouldn't the maximum distance be infinity? That is, if everything beyond 61.4 m is in focus, then why is there a maximum distance?


*Example Two*

Assume inputs:
- camera: Canon 1Dx
- aperture: ƒ/5.6
- focus distance 5.0 m (much closer than example one)

We learn the following:

- minimum distance in focus: 4.63 m
- maximum distance in focus: 5.43 m
- hyperfocal distance: 61.4 m

I understand that objects placed between 4.63 m and 5.43 m will appear sharp. And then, objects between 5.43 m and 61.4 m will NOT be sharp? And then beyond 61.4 m are sharp again?

---

Can someone please elaborate on my questions in Example One. In general (examples one and two), is my thinking or understanding correct?

If everything else stays the same, the further away you focus, the deeper the DoF.

Let's say you're focused 10 feet away, and the DoF is one foot.

As you adjust the focus point further back, you'll eventually hit a point where the DoF is two feet deep, and then four feet etc…

There's a point where the DoF will be so deep that everything from the distance you've focused all way to infinity is in focus. That's the hyper focal distance.