Depth of field

[Knight183]

How do you ensure everything is in focus? I am aware of various different techniques and how depth of field changes depending on the focal length. I am interested in what everybody does out in the field to get a landscape scene in focus.
I use Lumix cameras and when using the magnify view in manual focus, the aperture is always wide open. If I turn magnify off and manually focus with the aperture stopped down, it is hard to see whether the foreground or background are slightly soft as the focus peaking covers everything.
I would be interested to learn what everybody does with their Lumix cameras. There are no focus distance markings on modern lenses and the focus scale is not much help. I have used Photo Pills with a lot of success but I feel there should be an easier way or is it just experience and knowing your lenses.

 

[Mike Wingate]

Close down the aperture a bit, f8 or f11, focus point set to a mid point or nearer if detail in foreground, or further if detail is in the midground. Take a shot, check, correct for any areas out of focus. If you have the time, take numerous shots at different apertures, use a tripod and focus stack. Use an iPhone, everything is in focus.

 

[Knight183]

Close down the aperture a bit, f8 or f11, focus point set to a mid point or nearer if detail in foreground, or further if detail is in the midground. Take a shot, check, correct for any areas out of focus. If you have the time, take numerous shots at different apertures, use a tripod and focus stack. Use an iPhone, everything is in focus.

Thanks Mike, does seem rather hit and miss or a bit like trial and error. I am trying to get in the habit of reviewing my photos on the back of the screen more closely as I don't always do this.

 

[exakta]

As Mike wrote, focusing on a point in the middle of the range you want in focus is the starting point.

In addition to viewing test shots, try these two methods that come from the film days:

1. If your camera has a DOF preview button, use it.

2. If your lens has a scale, focus manually and check the scale (keeping in mind it's a rough measure...I don't know if any m43 cameras display a DOF scale on the screen...my Fuji X10 did). Use the scale to check the exact distance for various points in the image to give you an idea how deep you need the DOF to be.

P.S. Getting familiar with the hyperfocal distances for focal lengths/apertures you use often can be helpful.

As an example, for a 12mm wide angle at f8, focusing at 6 feet means everything from 3 feet to infinity is in focus. At f11, focusing at 4 feet means everything from 2 feet to infinity is in focus. For 9mm at f8, focusing at 3.3 feet means everything from 1.65 feet to infinity is in focus. At f11, focusing at 2.35 feet means everything from 1.17 feet to infinity is in focus.

 

[ERB]

http://www.dofmaster.com/dofjs.html

 

[PakkyT]

and how depth of field changes depending on the focal length.

along with aperture used and distance from subject to the camera. DoF depends on those three elements so there are other things you can play with to get more or less DoF.

As @ERB just posted, you can find DoF calculators online to play with different scenarios and you can also download phone apps so if you are not sure you can check your settings in the field for what you are about to shoot to get numbers which might help you better envision what you will capture.

If you are going out with a specific lens that day, you might want to run a few shooting scenarios through a DoF calculator and jot down a some cheat sheet notes of focal length, aperture, and distances with the resulting DoFs. For example, you are going out with just the Oly 75mm f1.8. A quick check of DoF shows that

• 75mm, f1.8, and 10 feet away from your subject your DoF is only a little over 3 inches.
• 100 feet with the same settings the DoF is over 29 feet.
• 10 feet then stopping down to f5.6 goes from 3 inches to almost 11 inches.
• 100 feet stopping down to f5.6 takes you from 29 feet to 116 feet DoF.
• 75mm at f1.8, anything from 647 feet or further you will have infinite depth of field so any aperture works.
• f5.6 will have infinite DoF at 214 feet and beyond.

So jot those scenarios down on a piece of paper and you will sort of have a rough guideline of where aperture should be for distances or where you should move, assuming you can, to get bigger or less DoF. Also keep in mind that DoF is the total area both before and after your focus point, so for the 116 feet one, assume roughly half that will be in front and in back of the focus point (it is actually biased to be more in the back but halving it gives you a quick idea) or where before and after your main focus point the focus will start to become "unacceptable".

One thing I have always done myself when shooting more landscape type shots or any subject where I have a lot of stuff close and far away from me, is I ignore the old advice to try to use hyperfocal distance or to stop down focusing a third of the way into the shot hoping that most of the shot is in reasonable focus. Instead, especially if I can not step down due to lower light, I decide what is the most important element of my shot and that is where I put my focus and let the DoF do whatever it is going to do. If I review the shot and find something near or far is still nor as sharp as I would like then I try to change something (walk closer or further away from the subject, change the aperture if possible, etc.), but I still focus on my main subject because I don't see a point in getting most of the scene "reasonably" in focus if the part I am most interested in ends up a tiny bit soft. I rather have those interesting bits as sharp as they can be even if the distance or the foreground gets a little "softer".

 

[Mike Wingate]

It makes you realize that the old lenses with apertures and depth of field scales were really useful. Use an iphone or ipad and the Panasonic app for better/easier viewing if depth of field and other stuff.

 

[Drdul]

I used to fuss about depth of field, but now I just focus on the object(s) I want to be in (sharpest) focus. I can live with some secondary elements being slightly out of focus, so long as the primary element(s) is in focus.

The depth of field concept is a bit misleading, as it is often presented as a range of distances within which everything is in focus. In reality, objects can only be in focus at one distance, and everything else is somewhat less in focus. After trying several different depth of field focusing strategies without great results, I now just focus on what matters. If I have the opportunity and it’s appropriate for the situation, I sometimes take a few shots at different focus distances so I can later compare and select the one I like. FWIW, I typically shoot around f5.0.

Having said all that, I find that 95% of the time the autofocus on my E-M5iii gets it right without me having to think about it, which is ideal as not thinking is my preferred way of operating.

 

[Drdul]

http://www.dofmaster.com/dofjs.html

I have tried a number of depth of field calculators, and I get the most realistic results (that best match my own experience with M43 cameras) from TrueDoF and OptimumCS by George Douvos: http://www.georgedouvos.com/index.html

 

[ERB]

I have tried a number of depth of field calculators, and I get the most realistic results (that best match my own experience with M43 cameras) from TrueDoF and OptimumCS by George Douvos: http://www.georgedouvos.com/index.html

This looks wonderfull!

Isn't time cameras show DOF NUMBERS inside the viewfinder, according to lens and selected focusing ?

 

[John King]

This looks wonderfull!

Isn't time cameras show DOF NUMBERS inside the viewfinder, according to lens and selected focusing ?

As Richard said, DoF is a useful concept that doesn't actually exist ...
Every lens is actually only in focus at the plane of focus, and some can't even manage that (e.g. field curvature).

 

[Holoholo55]

One thing I have always done myself when shooting more landscape type shots or any subject where I have a lot of stuff close and far away from me, is I ignore the old advice to try to use hyperfocal distance or to stop down focusing a third of the way into the shot hoping that most of the shot is in reasonable focus. Instead, especially if I can not step down due to lower light, I decide what is the most important element of my shot and that is where I put my focus and let the DoF do whatever it is going to do. If I review the shot and find something near or far is still nor as sharp as I would like then I try to change something (walk closer or further away from the subject, change the aperture if possible, etc.), but I still focus on my main subject because I don't see a point in getting most of the scene "reasonably" in focus if the part I am most interested in ends up a tiny bit soft. I rather have those interesting bits as sharp as they can be even if the distance or the foreground gets a little "softer".

I guess that's what I do. I focus on the vital point of the subject, and vary the aperture until I think I have the DOF I need. I don't often use the DOF preview (stop down) button, but I should. That is what it's for.

 

[PakkyT]

I don't often use the DOF preview (stop down) button, but I should. That is what it's for.

Yeah I never use it mostly because I forget it is even there (also I reprogrammed mine for something else) but because the image will often get dark enough to make it hard to see the DoF anyway and second because while that function once was useful to not waste film which cost real money, with digital if your DoF range is important to you for that shot, easier to simply take a couple/few shots with different settings or positions to hopefully cover it and pick the best one once you get home and see it on the big(ger) screen.

 

[PakkyT]

Isn't time cameras show DOF NUMBERS inside the viewfinder, according to lens and selected focusing ?

Agreed. With what are basically computers sitting in our hands, the camera knows the focal length, aperture, focus distance (when you perform a focus), and its own "Circle of Confusion", the DoF calculation should be stupid simple to display. In fact I would argue this would be a way better use of the "Depth of Field preview" button on the camera. Rather than just stopping down so you can squint at a tiny dark image, have that button instead lock focus distance (as if you are half pressing the shutter) and show the Dof calculation numbers (in addition to the tiny dark image if you like to look at that).

I don't understand why focus distance has always been recorded in the exif of most cameras (well Oly cameras in my experience) but most (Oly) cameras do not have any means to see that information while shooting or when reviewing your photos on the camera. In addition to DoF calculations, seems like this is a very practical piece of info to be able to call up when troubleshooting your photos for missed focus (especially back in the mirror days).

 

[Mack]

I have DOF Simulator offline version (They have it for phones too.) on laptop which gives me an idea of how much DOF I can get from a scale on it. Sometimes it is only 1/10 inch or so in close distances, but it does give me an idea and maybe a need for some alternate plan - like adding a few 1800 w/s flash units.

Was happy to see that a lot of the better manual focus lenses retained their DOF scale near the focusing ring like Voigtlander 29mm f/0.8 and Kipon 40mm f/0.85. If they have ample focus rotation, then the DOF scales are often expanded enough to make them useful. The Kipon 40mm I have has one of the widest DOF scales I've ever seen on a lens, but its focus rotation is a lot too and maybe why they made the rotation so extreme - sometimes too much, imho.

Nikon introduced an electronic DOF version in their S lenses which have the LCD for the distance, f/stop and focal length scale in their zooms. It's a small white bar that expands outwards to show you the DOF from the distance. Only problem with it is it may show only the distance, like 7 feet, so as the bar expands by closing down you really don't know what the outer distance limits are since they are not shown on the LCD. Good try though.

 

[Holoholo55]

Yeah I never use it mostly because I forget it is even there (also I reprogrammed mine for something else) but because the image will often get dark enough to make it hard to see the DoF anyway and second because while that function once was useful to not waste film which cost real money, with digital if your DoF range is important to you for that shot, easier to simply take a couple/few shots with different settings or positions to hopefully cover it and pick the best one once you get home and see it on the big(ger) screen.

Agreed about it getting dark if you're checking a small aperture. Same thing happened with 35 mm SLRs. So, even though the Canon FT-QL required me to stop down the lens to meter, it wasn't easy to actually SEE how much DOF I had.

 

[pdk42]

Best approach for deep DOF on a landscape is to use focus stacking. If you’re shooting wide and at f5.6, a couple of shots is usually enough - one near, one far. Stack in your favourite PP tool. PS does a decent job, but there are specialist tools available too - e.g. Helicon.

 

[exakta]

Rear screen of a Fuji X10 (from the manual). Why don't our cameras have this?

Subscribe to see EXIF info for this image (if available)

 

[ex machina]

I very often shoot on a tripod in low light environments and can get away with choosing a narrow aperture to get greater DOF. I often target a focus point midway between my camera and the furthest object in the view, and might take consecutive images with different focus points. Occasionally I'll merge these in post to get a kind of focus-stack.

Sometimes when I'm really concerned I'll turn on focus peaking and switch to manual focus mode and look to see if everything I want to be sharp is peaking on the LCD. This is generally more useful when I'm trying to isolate an object from the background.

 

[PakkyT]

Sometimes when I'm really concerned I'll turn on focus peaking and switch to manual focus mode and look to see if everything I want to be sharp is peaking on the LCD.

I am not sure I understand how that would work since A) peaking is to help you locate the focus plane rather than the depth of "acceptable sharp focus" and won't "peak" for less sharp things within the DoF range? and B) isn't peaking done with the lens aperture wide open where if your f1.8 lens is going to take the photo at f5.6, the peaking will be showing and working at f1.8?