Focusing on water, clouds, and fog

[bnnrcn]

As a rule of thumb ,we have to focus on 1/3 of the scene in order to get maximum sharpness in depth of field.So if the scene mainly consists of water like sea or a lake and if there are no solid objects on the water to focus on,is it still possible to focus on 1/3 of the water?

And same question for the clouds and fog..Sometimes if you are in the mountains,clouds or fog might be very near you.If there are no objects on the 1/3 of the scene,is it possible to focus on the clouds or fog?

[Saorsa]

You have a couple of options.

One is to go to manual focus and simply set the distance you want to use for focus.

The other is to use what Nikon calls AF-S instead of continuous focus (AF-C). Using that, you would focus on something at the desired distance and keep the shutter half depressed or use a focus lock function while framing the picture.

[Shadowman]

The 1/3 into the scene is commonly used when aperture is above f/8, usually around f/16-f/22. With the setup you are trying to achieve deep focus as opposed to a shallow focus with a wide aperture. You have to analyze the scene to determine if (1) the scene has enough visual elements to warrant deep focus (2) there is something of interest in the foreground, middle, and background (3) you have sufficient light to record each ground in a visually pleasing way.

[bnnrcn]

Thank you john,I asked this question because in landscape photography usually bigger f numbers are used like you said.And there might be some interesting scenes to shoot with a lot of water,fog or clouds.I didn't know if it was possible to focus without having a solid subject on the water or in the fog/clouds.Because sometimes there might be an interesting foreground subject and there might also be an interesting bacground subject but you may not find something solid to focus on 1/3 of the scene because there is blank water or fog there..

The 1/3 into the scene is commonly used when aperture is above f/8, usually around f/16-f/22. With the setup you are trying to achieve deep focus as opposed to a shallow focus with a wide aperture. You have to analyze the scene to determine if (1) the scene has enough visual elements to warrant deep focus (2) there is something of interest in the foreground, middle, and background (3) you have sufficient light to record each ground in a visually pleasing way.

[bnnrcn]

Thank you Saorsa ,my camera is a Canon and there is a similar focusing function in it.I use it when necessary, but I have simply used auto focus function in my sunset shots so far,because I didn't know I could have focused on blank water,I thought I always needed a solid subject to focus on.I also didn't know about 1/3 of the scene rule for focusing to get maximum sharpness in depth of field,I learnt about it by reading the tutorials in CIC.So,I think my camera focused on whatever subject nearby in the frame in my sunset shots.From know on I will be more careful about this matter when shooting landscapes and sunsets.

You have a couple of options


One is to go to manual focus and simply set the distance you want to use for focus.

The other is to use what Nikon calls AF-S instead of continuous focus (AF-C). Using that, you would focus on something at the desired distance and keep the shutter half depressed or use a focus lock function while framing the picture.

[Brownbear]

Hi Binnur,

I am going to expand on your question in a different thread in the General Section just so I don't hijack your thread.

PS I'm still trying to wrap my mind around the cloud reflection, too.

[Downrigger]

As a rule of thumb ,we have to focus on 1/3 of the scene in order to get maximum sharpness in depth of field.

Yours are good questions. This "rule of thumb" has always bothered me as it ignores that fact that "1/3 of the way into the field of view" might be 5 meters of a view that includes infinity, might be 1000 meters in a view that includes infinity, or might be 50 meters in a view where the horizon is at 100 meters, depending on the scene and how one wants to frame it. I think a very rough guide indeed.

[Manfred M]

Yours are good questions. This "rule of thumb" has always bothered me as it ignores that fact that "1/3 of the way into the field of view" might be 5 meters of a view that includes infinity, might be 1000 meters in a view that includes infinity, or might be 50 meters in a view where the horizon is at 100 meters, depending on the scene and how one wants to frame it. I think a very rough guide indeed.

And of course is related to the focal length you are shooting at as well as the distance to your subject. "Infinity" kicks in a lot closer distances at shorter focal lengths that with longer ones.

An f/8 setting on a 400mm lens is going to give you razor thin DoF whereas doing the same thing on a 14mm setting will mean just about everything is in focus.

[William W]

Whenever I have had an idea of how far away from me that I want my Plane of Sharp Focus to be: I can't really recall any time when I could not find something around me to achieve focus upon.

That doesn't mean that object will be "in the scene" - so I suggest that you look around - I bet that it would be an unusual circumstance that you could not find something around you, to lock your focus on.

WW

[Glenn NK]

And of course is related to the focal length you are shooting at as well as the distance to your subject. "Infinity" kicks in a lot closer distances at shorter focal lengths that with longer ones.

An f/8 setting on a 400mm lens is going to give you razor thin DoF whereas doing the same thing on a 14mm setting will mean just about everything is in focus.

Good point. Without bringing the focal length into the discussion, the answer is impossible and we're just chewing up forum bandwidth.

Christina posed a related question on the other thread - using a 10 mm lens. It hardly matters at all where you focus with a 10 mm lens at f/8. With a 200 mm lens it matters very much. So in the case of DOF, the focal length is the most important aspect. F/16 with a 200 mm lens is a very different situation.

G

[bnnrcn]

Hi,Bill..What you say is a good idea but what about the exposure then? When you focus on something out of scene,won't the camera give you an exposure value according to what you have focused on...And one more thing if I focus on something out of scene,how will I get clarity in my photo without focusing on anything?

Whenever I have had an idea of how far away from me that I want my Plane of Sharp Focus to be: I can't really recall any time when I could not find something around me to achieve focus upon.

That doesn't mean that object will be "in the scene" - so I suggest that you look around - I bet that it would be an unusual circumstance that you could not find something around you, to lock your focus on.

WW

[bnnrcn]

Thank you Manfred,there is a table which shows distribution of depth of field according to the focal length for max.sharpness in CIC's forum,that table doesn't tell you anything about F points.But there is also a depth of field calculator in the forum and it makes a calculation concidering the focal lengths and F points both.It is difficult to make such calculations for each scene when you are out shooting.So,I wonder is there an easier way so that I can go into the nature and shoot happily

And of course is related to the focal length you are shooting at as well as the distance to your subject. "Infinity" kicks in a lot closer distances at shorter focal lengths that with longer ones.

An f/8 setting on a 400mm lens is going to give you razor thin DoF whereas doing the same thing on a 14mm setting will mean just about everything is in focus.

[William W]

What you say is a good idea but what about the exposure then? When you focus on something out of scene,won't the camera give you an exposure value according to what you have focused on...

What camera do you have?

Most cameras allow for you to separate the Auto Focus and the Auto Exposure / Manual Exposure functions.

***

And one more thing if I focus on something out of scene,how will I get clarity in my photo without focusing on anything?

The camera does not achieve focus "on the object" it achieves focus "at the DISTANCE the Object is situated from the camera", so it doesn't matter what you focus on, provided that you are reasonable at estimating distances.


WW

[bnnrcn]

Thank you Bill ,now it is clear to me becasue I always had the idea to focus on the 'object in the proper distance' and that's why I was so confused,I always looked for an 'object'.My camera is Canon 1100D and I have AV,TV and Manuel modes ofcourse.So, I can set the exposure manually if I focus on something out of the scene..But what I understand from your comments,there is already no need to focus on something out of the scene,I can always focus in the scene I want to shoot without looking for an object And this 1/3 rule bothers me...Focusing distance depends on the focal length and aperture.There is a depth of field calculator in the related forum of CIC.But I find it difficult to make calculations for each scene when I go out for shooting.Is there a shorter and simpler way to make a decision about the focusing distance properly?

What camera do you have?

Most cameras allow for you to separate the Auto Focus and the Auto Exposure / Manual Exposure functions.

***



The camera does not achieve focus "on the object" it achieves focus "at the DISTANCE the Object is situated from the camera", so it doesn't matter what you focus on, provided that you are reasonable at estimating distances.


WW

[William W]

Perhaps I may not have understood your original question about the Auto Focus not being able to lock onto something in the scene.

So let me give you an example of what I am suggesting to address that question.

Let’s suppose that I want to make a photograph of this scene below and that I want to have reasonable focus from just in front of in front of the man and the yellow bucket through to the background (i.e. to infinity).

And also lest suppose that I CANNOT achieve any Auto Focus in that scene.

BUT I calculate that the man is about 40 meters from me and I also know from experience (or from the DoF Charts) that with the lens I am using at F/11, if I focus at 40 meters then I will have adequate Depth of Field to infinity and also a good bit in front of the man and the bucket.

So what I do is – make an exposure reading for the scene and lock that in (I would use the camera in Manual Mode and dial in my exposure deatils).

Then I need to achieve focus, but my Auto Focus will not lock on in that scene, so I look all about me and I find something that is 40 meters away from me (maybe a tree behind me for example) and focus on that.

Then I “Lock Focus” and then turn back and I frame the scene and I make the picture of the man and the bucket and the rainbow here:


“Pot of Gold”

WW

[bnnrcn]

Thank you very much Bill.Your answer is very clear.My real question was that I had always thougt that in auto focus function your camera just found the nearest objects in your scene unless you chose a suitable AF point among the AF points on the LCD screen for the object you want to shoot.This is what is written in the instruction manual of my camera.After reading tutorials in CIC I learnt about focusing distance and depth of field calculator.And combining my old knowledge and new knowledge I thought that I needed 'an object in the proper focusing distance' for max. sharpness but now,what I learn from you is that 'object doesn't matter,distance is important.So,is there an easy way of calculating proper focusing distance without using depth of field calculator.It is difficult making calculatıons when you go out for shooting.1/3 of the scene rule is not applicable for every situation.So,what am I going to do?

Perhaps I may not have understood your original question about the Auto Focus not being able to lock onto something in the scene.

So let me give you an example of what I am suggesting to address that question.

Let’s suppose that I want to make a photograph of this scene below and that I want to have reasonable focus from just in front of in front of the man and the yellow bucket through to the background (i.e. to infinity).

And also lest suppose that I CANNOT achieve any Auto Focus in that scene.

BUT I calculate that the man is about 40 meters from me and I also know from experience (or from the DoF Charts) that with the lens I am using at F/11, if I focus at 40 meters then I will have adequate Depth of Field to infinity and also a good bit in front of the man and the bucket.

So what I do is – make an exposure reading for the scene and lock that in (I would use the camera in Manual Mode and dial in my exposure deatils).

Then I need to achieve focus, but my Auto Focus will not lock on in that scene, so I look all about me and I find something that is 40 meters away from me (maybe a tree behind me for example) and focus on that.

Then I “Lock Focus” and then turn back and I frame the scene and I make the picture of the man and the bucket and the rainbow here:


“Pot of Gold”

WW

[bnnrcn]

Manfred and Bill ,I think I have found the answer to my question about guessing right focusing distance without depth of field calculator.Today I spent some time on depth of field calculator and I have realised that I don't have a big problem with wide angles when f stop is between 8 and 16 which I will usually be using.It is possible to get clarity at infinty with short focusing distances.So there is no need to panic But situation was different with 300 mm focal length and between f8 and f16,there is nearly no depth of field with a short focusing distance.Your focusing point has to be really far if you want a clear depth of field.So I feel relieved now..Thank you very much

[William W]

. . . After reading tutorials in CIC I learnt about focusing distance and depth of field calculator. . . is there an easy way of calculating proper focusing distance without using depth of field calculator. It is difficult making calculatıons when you go out for shooting. 1/3 of the scene rule is not applicable for every situation. So,what am I going to do?

OK, I understand: it can be difficult and also time consuming making DoF calculations when we are out having fun shooting.

Let me outline what I do.

I don’t often make DoF Calculations using a DoF Calculator: but that is what ‘experience’ is all about. When I began Photography I did use a DoF Calculator more often. All I had then was a Cardboard Dial DoF Calculator and also the DoF formulae to work out the DoF with paper and pen: but today we have computer applications which are very handy to use.

I use a free downloadable software, known as: “FCalc”. I usually carry a small notebook computer in my camera bag and it has that program on it.

Also I still have my Cardboard Dial DoF Calculator (actually I have two of them). One is in my Kodak Professional Handbook and I usually carry that handbook with me as it has a Standard Grey Card and also a Standard Colour Patch Chart in it too.

I am not saying that I use all this gear each time I go out with my camera bag: I am saying that I have all this gear to use when I need to use it. Also I am not saying you (or anyone) need to get all this gear.

***

Simply speaking we can separate Photography into three main types:

> Landscapes

> Portraits

> Macro & Close-up.

Accurate DoF Calculations are not really all that necessary for most shooting scenarios. So I suggest that you do not get too concerned about needing to make a calculation for every photo that you take.

***

LANDSCAPES:

Now let’s talk about shooting only Landscape Scenes. You will read about focussing at the “Hyperfocal Distance” to attain the maximum Depth of Field – and that is good to know. You’ll also read about “Diffraction when using small apertures” and that is good to know too.

But for most Landscape Scenes, focusing at or just before infinity and using and aperture F/8 to F/16 will allow for most circumstances really nice picture with adequate DoF: rather than DoF it usually is far more important to see and think about:

> the LIGHT
> the FRAMING and COMPOSITION
> the SHUTTER SPEED
> the STABILITY of the Camera and Lens

So, for most landscape scenes, I don’t use the ‘⅓ - ⅔ Rule of Thumb’ – I just focus at or just before infinity and concentrate more on those other factors I have listed.

Obviously, for Landscape Scene where we want something in the Foreground to be in acceptable focus and we want the Horizon to also to be in acceptable focus we need to have some knowledge about DoF. For example, the shot of the man and the rainbow above.

For that particular shot I estimated the distance from the man to me and then I knew (simply from experience) that if I used F/11~F/16 and focussed on the man, then the horizon would be in sharp enough focus for the shot.

If I did not have that experience and knowledge:

• I could have opened up my computer notebook or my cardboard dial calculator and made a calculation to confirm the DoF.
• Also (and more importantly) I could have just used the smallest aperture available on my lens (F/32) and taken two shots - one focussing on the man and one focussed at infinity and hoped for the best. At least one of those would have the man in sharp focus and in reality, a slightly out of focus rainbow would not be the end of my Photographic life . . . It was more important for me to make the photograph before the rainbow disappeared or the man moved.

If you have more time and you are setting up a tripod for a particular Landscape Shot and there is a particular foreground object that you want in focus, then certainly whip out a DoF calculator if you need to and plan the shot carefully . . . but you will still have to wait for the light to be right and you might take a few shots before you are satisfied you have the best light.

***

PORTRAITS:

When we make Portraits we are usually shooting at a restricted range of distances – from about 3 ft (1 metre) to about 60ft (20 metres)

The DEPTH OF FIELD for any APERTURE is directly related the FRAMING of any Portrait for any one camera FORMAT – this is the Axiom of Depth of Field.

As an example what this means is, if you frame me in your viewfinder so that my belt buckle to my head fills the frame, it doesn’t matter what lens you use, provided you use the same camera format and the same aperture, for all practical purposes the DoF will remain the same.

So I have learnt the DoF for each of these three main shots; each for three apertures (F/2.8; F/5.6; F/11); for both framing in Vertical and Horizontal Camera Orientations and that is sufficient for mostly all of my Portraiture Photography.

If you want to do this then I suggest you make two cheat sheets for the 18 Depths of Fields that you need to memorize - make one for Vertical Camera Orientation and one for Horizontal Camera Orientation.

However, even with a lot of experience under my belt, where I am very careful is for GROUP PORTRAITURE, when for some reason I need to use a larger aperture and I do not KNOW FOR CERTAIN if I am safe to use that larger aperture - I will indeed check the DoF calculator and also use a tape measure to confirm the Subject Distance.

***

MACRO and CLOSE UPS

Is an area that I don’t often go to and is where getting enough DoF is sometimes a real pain for most Photographers; I don’t think that many Macro workers actually use any DoF calculations, but they use other means like focus stacking and seem to use very small apertures most of the time.

WW

[William W]

I think I have found the answer to my question about guessing right focusing distance without depth of field calculator. Today I spent some time on depth of field calculator and I have realised that I don't have a big problem with wide angles when f stop is between 8 and 16 which I will usually be using.

WELL DONE!

Bravo! / Brava!


WW

[bnnrcn]

Bill,thank you very much ..I'm quite clear about the subject know.I agree with you about group portraiture,it is more difficult,because there are more than one people and we have to take a clear and sharp picture of all of them which is difficult with small f stops.But we want to use a small f stop because we want a blurred background to make the group stand out.So it is much better to use DOF calculations and measure the subject distance as you said.Thanks again

OK, I understand: it can be difficult and also time consuming making DoF calculations when we are out having fun shooting.

Let me outline what I do.

I don’t often make DoF Calculations using a DoF Calculator: but that is what ‘experience’ is all about. When I began Photography I did use a DoF Calculator more often. All I had then was a Cardboard Dial DoF Calculator and also the DoF formulae to work out the DoF with paper and pen: but today we have computer applications which are very handy to use.

I use a free downloadable software, known as: “FCalc”. I usually carry a small notebook computer in my camera bag and it has that program on it.

Also I still have my Cardboard Dial DoF Calculator (actually I have two of them). One is in my Kodak Professional Handbook and I usually carry that handbook with me as it has a Standard Grey Card and also a Standard Colour Patch Chart in it too.

I am not saying that I use all this gear each time I go out with my camera bag: I am saying that I have all this gear to use when I need to use it. Also I am not saying you (or anyone) need to get all this gear.

***

Simply speaking we can separate Photography into three main types:

> Landscapes

> Portraits

> Macro & Close-up.

Accurate DoF Calculations are not really all that necessary for most shooting scenarios. So I suggest that you do not get too concerned about needing to make a calculation for every photo that you take.

***

LANDSCAPES:

Now let’s talk about shooting only Landscape Scenes. You will read about focussing at the “Hyperfocal Distance” to attain the maximum Depth of Field – and that is good to know. You’ll also read about “Diffraction when using small apertures” and that is good to know too.

But for most Landscape Scenes, focusing at or just before infinity and using and aperture F/8 to F/16 will allow for most circumstances really nice picture with adequate DoF: rather than DoF it usually is far more important to see and think about:

> the LIGHT
> the FRAMING and COMPOSITION
> the SHUTTER SPEED
> the STABILITY of the Camera and Lens

So, for most landscape scenes, I don’t use the ‘⅓ - ⅔ Rule of Thumb’ – I just focus at or just before infinity and concentrate more on those other factors I have listed.

Obviously, for Landscape Scene where we want something in the Foreground to be in acceptable focus and we want the Horizon to also to be in acceptable focus we need to have some knowledge about DoF. For example, the shot of the man and the rainbow above.

For that particular shot I estimated the distance from the man to me and then I knew (simply from experience) that if I used F/11~F/16 and focussed on the man, then the horizon would be in sharp enough focus for the shot.

If I did not have that experience and knowledge:

• I could have opened up my computer notebook or my cardboard dial calculator and made a calculation to confirm the DoF.
• Also (and more importantly) I could have just used the smallest aperture available on my lens (F/32) and taken two shots - one focussing on the man and one focussed at infinity and hoped for the best. At least one of those would have the man in sharp focus and in reality, a slightly out of focus rainbow would not be the end of my Photographic life . . . It was more important for me to make the photograph before the rainbow disappeared or the man moved.

If you have more time and you are setting up a tripod for a particular Landscape Shot and there is a particular foreground object that you want in focus, then certainly whip out a DoF calculator if you need to and plan the shot carefully . . . but you will still have to wait for the light to be right and you might take a few shots before you are satisfied you have the best light.

***

PORTRAITS:

When we make Portraits we are usually shooting at a restricted range of distances – from about 3 ft (1 metre) to about 60ft (20 metres)

The DEPTH OF FIELD for any APERTURE is directly related the FRAMING of any Portrait for any one camera FORMAT – this is the Axiom of Depth of Field.

As an example what this means is, if you frame me in your viewfinder so that my belt buckle to my head fills the frame, it doesn’t matter what lens you use, provided you use the same camera format and the same aperture, for all practical purposes the DoF will remain the same.

So I have learnt the DoF for each of these three main shots; each for three apertures (F/2.8; F/5.6; F/11); for both framing in Vertical and Horizontal Camera Orientations and that is sufficient for mostly all of my Portraiture Photography.

If you want to do this then I suggest you make two cheat sheets for the 18 Depths of Fields that you need to memorize - make one for Vertical Camera Orientation and one for Horizontal Camera Orientation.

However, even with a lot of experience under my belt, where I am very careful is for GROUP PORTRAITURE, when for some reason I need to use a larger aperture and I do not KNOW FOR CERTAIN if I am safe to use that larger aperture - I will indeed check the DoF calculator and also use a tape measure to confirm the Subject Distance.

***

MACRO and CLOSE UPS

Is an area that I don’t often go to and is where getting enough DoF is sometimes a real pain for most Photographers; I don’t think that many Macro workers actually use any DoF calculations, but they use other means like focus stacking and seem to use very small apertures most of the time.

WW