# Depth of Field question



## Ch33chi (Mar 3, 2014)

How can i understand depth of field better? I have been reading up on it, i know what it is but how can i improve my images. Any tips? 
or should i just watch youtube videos and read books until my eyes bleed? 



View attachment 67978


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## Gavjenks (Mar 3, 2014)

Well if you really do understand it, then no you shouldn't read more books. You should just go out and use it!

You say "improve my images." This implies that you did try it out and got some problems that you didn't expect?  If so, what were those problems, specifically, and we can help you solve them.

Example photos always help too


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## hirejn (Mar 3, 2014)

As with anything in photography, go out and do it. Experiment and practice until you understand it.


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## Designer (Mar 3, 2014)

Understanding Depth of Field in Photography


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## 71M (Mar 3, 2014)

Ch33chi said:


> How can i understand depth of field better?


By using different f-stops.
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Depth of field - Wikipedia, the free encyclopedia


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## DreamPhotos (Mar 3, 2014)

Are you just trying to figure out how to have better bokeh?


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## Designer (Mar 3, 2014)

Online Depth of Field Calculator


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## 480sparky (Mar 3, 2014)

At f/25 (what was used for the church photo), you've softened the image due to diffraction at that setting.  F/8, maybe f/11 at most.


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## JerryLove (Mar 3, 2014)

Canon Explains Exposure

Click "Play". 

Try different apertures (make sure to adjust ISO / speed to keep the light level correct). Watch DoF change.


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## KmH (Mar 3, 2014)

Ch33chi said:


> . . . I have been reading up on it, i know what it is but how can i improve my images. Any tips?


Next you need to understand how to control the DoF by the choice of lens focal length, point of focus distance, and lens aperture you use 

You also need to understand how the distribution of the DoF changes as the lens focal length, point of focus distance, and lens aperture are changed. For many senic type shots you'll want to be familiar with hyperfocus - Understanding Your Camera's Hyperfocal Distance

Carefully consider the light quality and it's direction before you release the shutter.

Learn how to use the histogram display on the rear LCD to judge exposure, and understand when it's appropriate to change the light metering mode your camera is using.

Understanding Camera Metering and Exposure
Understanding Digital Camera Histograms: Tones and Contrast
Understanding Digital Camera Histograms: Luminosity and Color


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## timor (Mar 4, 2014)

This is very good, short and to the point explanation of basic characteristics of optical system.
Depth of Field
The definition on the DoF is right at the top of the page
I suggest you read the other stuff as well.
Good luck.


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## Light Guru (Mar 4, 2014)

Ch33chi said:


> How can i understand depth of field better? I have been reading up on it, i know what it is but how can i improve my images. Any tips?
> or should i just watch youtube videos and read books until my eyes bleed?
> 
> 
> ...



How do you feel that the image you posted has a problem with depth of field? 

The issue I see with the photo is the exposure.  The image is underexposed.


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## shaylou (Mar 5, 2014)

To answer your question I would suggest simply using dof to isolate your subjects. Practicing this will teach you all that is needed to understand dof. You will need to look closely at your shots to see how your adjustments (aperture, focal length) effects your shot.


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## minicoop1985 (Mar 6, 2014)

Another thing that could help is to get your hands on a camera that will allow you to do a DOF preview. I know the Sony a55 does it, but if you're not on the A-mount, there's tons of film cameras that do it. That's the best way to see it in action AS you're shooting. My Olympus OM-1n and Minolta SRT-101 do it, and both are pretty easy to find on eBay or the like.

One of the stranger aspects of DOF is the way it expands the further you are from the subject. Let's say, for instance, that your 50mm 1.8 lens set to f1.8 has a DOF of 2" at 3 feet away (I'm making the numbers up for illustrative purposes-don't tar/feather me again PLEASE). At 10 feet, that DOF will be close to a foot. At 50 feet, it will be 20 or so feet. I think that should make sense.


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## vimwiz (Mar 6, 2014)

> , there's tons of film cameras that do it.



Really? I dont think a single one of my Canons does.


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## 480sparky (Mar 6, 2014)

vimwiz said:


> Really? I dont think a single one of my Canons does.



Check the manual.


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## Gavjenks (Mar 6, 2014)

Both my T2i and 6D from canon have DOF preview. It is a small black easy to miss button on the front faceplate right around the lens mount somewhere. Doesn't work super well though. More useful on film cameras for metering, if the body doesnt know what aperture you have set. It's dark and hard to tell what's in focus anyway.

On a modern body, you can however exposure compensate up higher, then DOF preview with LCD mode on, to get a bright preview with proper DOF, if you really need to.


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## vimwiz (Mar 6, 2014)

Gavjenks said:


> w. It is a small black easy to miss button on the front faceplate right around the lens mount somewhere. More useful on film cameras for metering



Neither my AV-1 or T70 has this, but the T90 does (its a lever). How odd. Maybe it only went on "pro" bodies?  - This is backed up by the fact that neither does my 1100D (though you can map it to a button in SW) while my old Film EOS 1 does (as you describe).


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## Gavjenks (Mar 6, 2014)

Vimwiz: On many styles of older cameras, the DOF preview is often built into the LENS rather than the body. 
I would be pretty surprised if there wasn't one in either location. There could also be one in BOTH in some transitional models


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## minicoop1985 (Mar 6, 2014)

Yeah, on my 7D, I think it's a button on the body (I should really look into that), as it is with my wife's Sony a55. On an Olympus OM series lens, there's two buttons 180 degrees from each other. One releases the lens from the camera, the other is the DOF preview/stop down. On my Minolta XG-SE, it's a button on the body (I think, I could be confusing it with the other XGs I've had). With my Hasselblad 1600f, it's completely manual-you set the aperture, then compose, then stop the aperture down, then take the shot. It's easy to forget to stop it down to say the least... But my point is that A. not all cameras have it, and 2. of the ones that do, they're all different. So, basically, what Gavjenks said, but poorly worded and very drawn out.


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## TCampbell (Mar 6, 2014)

vimwiz said:


> > , there's tons of film cameras that do it.
> 
> 
> 
> Really? I dont think a single one of my Canons does.



Every Canon camera I've every had (well... film and DSLR, we'll skip the point & shoots) does it.  Usually (but not always) the button is on the lower right or lower left side of the lens (on the camera body... but near lens flange.)

My favorite teaching aid for DoF is to grab a bunch of something... wine bottles, soup cans, doesn't really matter what it is.  Line them all up in a row leaving about 1' of space between each.  Go to one end of the row and focus on the middle one.  Take a shot at each different f/stop and compare.

You'll quickly see how the depth of field works... initially only maybe the center bottle is focused... but then you'll start to notice nearer and farther bottles are focused and at very high f-stops you'll notice they're pretty much all focused.


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## minicoop1985 (Mar 6, 2014)

You'll probably also find where your lens performs best too. My Tamron 17-50 f2.8 does best somewhere near f4-11, but at 16 and above, quality falls off a bit. At f22, it's somewhat soft due to diffraction I believe-correct me if I'm wrong there.


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## Gavjenks (Mar 6, 2014)

Diffraction is an issue more at the sensor level than the lens (depending on your pixel size for the actual physics of it, as well as your total sensor size due to the effect it has on final print size that makes you able to see it or not), but yes at f/22, diffraction is certainly limiting your sharpness in most 35mm or smaller format cameras and normal print sizes.

Shooting f/35 in large format (4"x5" film), for example, is totally normal and no big thang (equivalent for DOF and diffraction of something like f/5.6 or f/8 in digital camera formats), whereas in crop format it would be horrendously crippling.


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## glun (Apr 2, 2014)

Ch33chi said:


> How can i understand depth of field better? I have been reading up on it, i know what it is but how can i improve my images. Any tips?



The best thing is to try it out. Try different focal length and aperture with the same object. This depends on the type of lens you have as well.


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## shaylou (Apr 7, 2014)

Forgive me if it's been said. When you really understand dof you will know how to use it to make your shots better.

 I can tell you the one thing that really made dof click for me is when I set up my camera with my laptop (tether) and set up a display to shoot. I played with the fstops while reviewing on my laptop and was able to really see what was going on and how the aperture effected the shot. Then I messed with the focal length and reviewed the shots on the big screen and everything was much clearer to me after that. Doing this opened my eyes to really understanding dof and how it effects my work. I would highly suggest you give it a try. Even if you feel like you understand it.
I hope that helps. If you do try it let me know how it goes.


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## shaylou (Apr 7, 2014)

Designer said:


> Understanding Depth of Field in Photography



That's a great website. I recommend it to others so much I wonder if they think I work for it. lol


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## shaylou (Apr 7, 2014)

minicoop1985 said:


> Another thing that could help is to get your hands on a camera that will allow you to do a DOF preview. I know the Sony a55 does it, but if you're not on the A-mount, there's tons of film cameras that do it. That's the best way to see it in action AS you're shooting. My Olympus OM-1n and Minolta SRT-101 do it, and both are pretty easy to find on eBay or the like.
> 
> 
> all 3 of my canons have this preview button and all 3 of them seem useless to me. I can not see much at all when I tried using them. Not sure the point really. After using dof enough you get a good feel for where you need to be and with digital it is way easy to snap a shot and zoom in on the display to check your dof. At that point you can adjust from there. I thought it was odd that a pro body would have that. I'm not even a pro and I don't use it.


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## minicoop1985 (Apr 7, 2014)

If you shoot macro, it becomes incredibly helpful. Sometimes just an idea/feel for where it is isn't enough.


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## Darkershadesofbrown (Apr 10, 2014)

Depth of field really has more to do with the aperture capabilities of your lens. The lower that number the more creamy the image will be.


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## Ysarex (Apr 10, 2014)

Darkershadesofbrown said:


> Depth of field really has more to do with the aperture capabilities of your lens. The lower that number the more creamy the image will be.



Alterations in magnification are going to have a more pronounced effect on DOF than changes in aperture. Both need to be controlled to achieve an end result. Managing magnification of relative distances gives you a broader range of control than the lens aperture.

Joe


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