hypofocal distance

[An drew]

That is not a sure fire way to get deep DoF. What if you are shooting at 16mm and at F2.8. Will putting the focus between 1.2 and infinity work still? I believe it is better to know for sure, than to do all these trail and error "magic" settings. (FYI, there are no magic settings).

From my DOF calculator, at 16mm and f2.8, if the focus distance is just 6m, you will get dof from 2.76m to infinity. Surely focusing between 1.2 and infinity will give you that.

This is where I really lost you.

How many people actually do own tilt-shift lenses? And you are asking people to get a $3k tilt lens and apply Scheimpflug over hyperfocal distance focusing that can be applied to a kit lens...

BTW getting a tilt lens and applying Scheimpflug do not give you a deeper DoF. It just shifts the plane of Dof to an angle not parallel to the sensor. You still get OOF areas, just in different areas now.

Just my 2 cents.

Sorry I'm just giving the best solution.

 

[daredevil123]

From my DOF calculator, at 16mm and f2.8, if the focus distance is just 6m, you will get dof from 2.76m to infinity. Surely focusing between 1.2 and infinity will give you that.

"Surely" is a heavy word, especially if your assumptions are totally wrong.

Hyperfocal distance at 16mm, F2.8 for a APS-C camera is 4.54m. This means you will get very deep DoF if you focus at 4.54m or further... (this includes 6m). But you WILL NOT get that deep DoF if your focus distance is BELOW 4.54.

You said anything from 1.2m will work. Ok... Let's say you pick 2m then. Guess what is the depth of field range? Everything in 1.38m to 3.56m only will be in focus... meaning everything else will be OOF. See for yourself.

From dofmaster online depth of field calculator:

Focal Length: 16mm
Aperture: F2.8
Circle of Confusion: 0.02
Subject distance 2 m

Depth of field
Near limit 1.39 m
Far limit 3.56 m
Total 2.17 m

In front of subject 0.61 m (28%)
Behind subject 1.56 m (72%)

Hyperfocal distance 4.54 m
Circle of confusion 0.02 mm

So, don't assume. Know it well, so when you shoot you will not blotch up your shot. And at the same time, it is better to research and know what you are saying is true, before you insist it is, and tell newbies that is the truth.

Hope this clear things up.

 

[An drew]

Hee hee, I will still tell the newbie to focus right between 1.2 and infinity. If the newbie is the type that choose to focus at 1.3m instead then he/she should get a dof calculator or ask you for more advice. Which is what?

 

[Muckafutha]

Yup... for older lenses, that should be correct. [/QUOT

Just like to ask: I thought setting the infinity symbol to the aperture marking just tells you what is the range where the objects will be in focus? Then after that we still need to focus our lens to that distance? And we also need to set the aperture to that particular aperture right?

I'm confused.

Edit: Oh I think I understand already, after looking at my GSN.

 

[An drew]

http://www.pentaxforums.com/forums/...ck-sharpness-distance-setting-front-lens.html

Here is more information which might help the TS.

 

[daredevil123]

Hee hee, I will still tell the newbie to focus right between 1.2 and infinity. If the newbie is the type that choose to focus at 1.3m instead then he/she should get a dof calculator or ask you for more advice. Which is what?

So I guess I have to ask newbies to not listen to any advice you give. Because you are asking them to take a chance and possibly do the wrong thing and not get the shot.

Just asking... Have you actually seen the distance scale of a Tokina 11-16 in person? It shows 1m, 2m, and right away becomes infinity. The range from 1m to 4.54m is more than 3/4 of the space between 1 to infinity. Asking the newbie to concentrate on 1.2 to infinity, you are asking a newbie to take a chance. And the chance that the newbie will get bad focusing is more than 75% chance if he/she decides to shoot at F2.8.

IMHO, this is definitely bad practice and I strongly advise against it. Want to learn, then learn the right things. Don't learn the wrong things. Or else will end up like yourself, telling others the wrong things and giving bad advice.

People who want to learn it the right way, I recommend this article on how to do it right. Tons of examples given, and some practical advice on how to do it right.
http://darthbertz.blogspot.com/2010/07/getting-everything-into-focus.html

 

[daredevil123]

Yup... for older lenses, that should be correct. [/QUOT

Just like to ask: I thought setting the infinity symbol to the aperture marking just tells you what is the range where the objects will be in focus? Then after that we still need to focus our lens to that distance? And we also need to set the aperture to that particular aperture right?

I'm confused.

Edit: Oh I think I understand already, after looking at my GSN.

I think you already noticed it. By turning so that the infinity marker lines up with the aperture DoF marker, you will notice that you are indeed focusing at the hyperfocal distance..

And if you look at the other DoF marker on the other end, you will see it lines up with the beginning distance of the DoF. That is one other reason why I love old legacy lenses so much.

 

[An drew]

It shows 1m, 2m, and right away becomes infinity.

Thanks for the correction, it starts at 2m not 1.2m. So this brings it even closer to the hyperfocal distance. So all you need to do is to turn the focus ring to right between 2 and infinity.

 

[Anthony Lee]

I think you already noticed it. By turning so that the infinity marker lines up with the aperture DoF marker, you will notice that you are indeed focusing at the hyperfocal distance..

And if you look at the other DoF marker on the other end, you will see it lines up with the beginning distance of the DoF. That is one other reason why I love old legacy lenses so much.

A simple logic, yet so complicating to most. What has modern technologies turn us into? How can one not understand DOF when one uses a DSLR? I learnt this in school in the 50s', don't you guys do the same now? Pick up some old legacy lenses if you want to do this big thing called "hyperfocal distance" shooting and you do not need any fanciful AF at all.

 

[An drew]

People who want to learn it the right way, I recommend this article on how to do it right. Tons of examples given, and some practical advice on how to do it right.
http://darthbertz.blogspot.com/2010/07/getting-everything-into-focus.html

Good article, thanks. if you focus between 2 and infinity it will be a little further than the hyperfocal distance. But no problem as said in the article.

What if I do not have a distance scale on my lens, and/or I do not know whether I can focus at the exact spot?

Do not worry. Hyperfocal distance will work further away. So if you are not sure, just focus on a spot further away than the calculated hyperfocal distance, and everything from half of the distance of that spot to infinity will be in focus.

 

[daredevil123]

Good article, thanks. if you focus between 2 and infinity it will be a little further than the hyperfocal distance. But no problem as said in the article.

What if I do not have a distance scale on my lens, and/or I do not know whether I can focus at the exact spot?

Do not worry. Hyperfocal distance will work further away. So if you are not sure, just focus on a spot further away than the calculated hyperfocal distance, and everything from half of the distance of that spot to infinity will be in focus.

Thanks. I always try to be as detailed as possible when writing articles.

Thing is, it is not always the case, using 2m to infinity. What if there is a rock or pebble that one wants to use a foreground? What if the aperture is large? There are just too many unknowns to just use "2m to infinity" all the time. The problem is not further away, but nearer. if focus distance is closer than hyperfocal, you will mess up the shot. There are no definites, but in situations like shooting a sunrise or sunset, where shooter is working in the dark, laying on filters, setting up remotes and tripods, it is easy to err if just based on a general rule as general as "2m to infinity".

My personal standpoint is, not to leave anything to chance. Get the technicalities right and be sure of it, so you can concentrate on the artistic part photographer.

 

[An drew]

thelight, the answer is estimation.

What if I do not have a distance scale on my lens, and/or I do not know whether I can focus at the exact spot?

Do not worry. Hyperfocal distance will work further away. So if you are not sure, just focus on a spot further away than the calculated hyperfocal distance, and everything from half of the distance of that spot to infinity will be in focus.

from my blog post at http://darthbertz.blogspot.com/2010/07/getting-everything-into-focus.html. I think I listed some examples in there as well on this.

You are right. Have to estimate.

My personal standpoint is, not to leave anything to chance. Get the technicalities right and be sure of it, so you can concentrate on the artistic part photographer.

Good advice.

 

[kinky1971]

Hi daredevil123
If I am to take a landscape, I am safe to have all in focus if I point at a mountain say 1km away?

thelight, the answer is estimation.

What if I do not have a distance scale on my lens, and/or I do not know whether I can focus at the exact spot?

Do not worry. Hyperfocal distance will work further away. So if you are not sure, just focus on a spot further away than the calculated hyperfocal distance, and everything from half of the distance of that spot to infinity will be in focus.

from my blog post at http://darthbertz.blogspot.com/2010/07/getting-everything-into-focus.html. I think I listed some examples in there as well on this.

 

[daredevil123]

Hi daredevil123
If I am to take a landscape, I am safe to have all in focus if I point at a mountain say 1km away?

It depends on what you mean by "all" and what you have included in the frame.

Please read the following article to understand how to "get it all into focus":
http://darthbertz.blogspot.com/2010/07/getting-everything-into-focus.html

 

[kinky1971]

Hi daredevil123

I have these parameters:

1. Focal Length: 12mm
2. Aperture: F/4
3. Circle of Confusion: (Using a D90)
4. Subject distance: 2m
5. Online Calculator gives a hyperfocal distance of 1.81m; near limit is 0.95m to infinity.


I think what I am trying to seek is how to I gauge the subject distance? It is pretty tough to do it. If I misjudge the distance and have it as 4m, my near limit becomes 1.24m.

By experience and trial&error? :dunno:

Regards
DAve

It depends on what you mean by "all" and what you have included in the frame.

Please read the following article to understand how to "get it all into focus":
http://darthbertz.blogspot.com/2010/07/getting-everything-into-focus.html

 

[daredevil123]

Hi daredevil123

I have these parameters:

1. Focal Length: 12mm
2. Aperture: F/4
3. Circle of Confusion: (Using a D90)
4. Subject distance: 2m
5. Online Calculator gives a hyperfocal distance of 1.81m; near limit is 0.95m to infinity.


I think what I am trying to seek is how to I gauge the subject distance? It is pretty tough to do it. If I misjudge the distance and have it as 4m, my near limit becomes 1.24m.

By experience and trial&error? :dunno:

Regards
DAve

How to guage distance is best done using your own height. If you are 1.7m, you know about 2 body lengths of yourself will be around 3 to 3.5 m. That would be ok. Also remember things that you are familiar with... like a basketball hoop is 3m also. Things like that.