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Old Dec 24, 2004, 11:28 PM   #1
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Here is a sample shot of my son taken with my Canon 20d. If you look at the lower left hand side, you can notice the overall and shoulder is very clear and the rest of the image isnt as clear. I had to resize to allow the image here but at the bigger size it's much more evident. NHL, I think this is what you were mentioning in your post. Jcarboski
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Old Dec 24, 2004, 11:39 PM   #2
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hey there...

it looks alright to me...

are you talking about the background being out of focus? that's from a large arperture/zoom combination...

what mode were you in? could you find the settings in camera for me?

the DOF (depth of field, or depth of focus) is pretty small... so that's why only the shoulder is "really" sharp...the face isn't too bad, and you can see in the hat where the DOF ends (where it goes from sharp to blurry)

shots taken indoor, especially at night, are tough to do, with any camera...but this shot looks ok to me!

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Old Dec 24, 2004, 11:56 PM   #3
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Another point is what focus mode did you have it on? If you had all sensors being used, at this close range it could make a difference if they settled on the body and not the eyes. When doing relatively close up portraits, I switch to just the centre autofocus sensor, line up over the eye, focus, reframe and shoot. If you do this 3 or 4 times quickly for the same shot, you should end up with a crystal clear sharp shot of the face, and more importantly, the eyes. Just my opinion.
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Old Dec 25, 2004, 12:32 AM   #4
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It looks like your camera is working OK, you are just experiencing a shallow depth of field.
I made a guess that you were about 36 inches from your subject.

Running your eXif parms into DOFMaster
Camera= 20d
Actual Focal length = 54mm
Aperture used= F4
Distance to Subject = 36 inches(My guess)

You get:
Near limit of acceptable sharpness = 35.2 inches
Far limit of acceptable sharpness = 36.8 inches
Total depth of field = 1.62 inches

So for this camera/lens/Aperture/distance combination you only get 1.62 inch of an acceptable sharp depth of field.
Even at F16 the DOF would only grow to 6.51 inches.
This shallow DOF would hold true for any camera and lens matching this focal length.

However increasing the lens to subject distance does greatly increase the DOF, at 10 feet and F8 you get aDOF of 3.2 feet.

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Old Dec 25, 2004, 7:50 AM   #5
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By chance were you used to a smaller digicam before the 20D?

Most (all, really) smaller pocket cameras have a really small sensor size. In compairson DSLRs have a much larger sensor. This effects the DOF very much. For some things this is a big advantage for pocket cameras and for other uses it's an advantage to the DSLR.

If you want a good separation between the background and the subject (like in a portrate) then its a good thing. But you need to stop down (larger fstop/smaller aperture) the lens to get the larger DOF you need.

I tried to look at the picture in the EOSViewer but it wouldn't open it. Probably because some of the EXIF data was missing. The result was that I wasn't able to see what the AF mode was and which AF point was used to take the picture. Like PeterP said, it's best to use the center AF point and refocus (if the kid is sitting still) that way you get the DOF placed where you want. This might not create as much DOF as you want, but at least the critical part (the kids face) is in sharpest focus.

That is a nice DOF calculator. Handy link.

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Old Dec 25, 2004, 10:14 AM   #6
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I have owned the Canon digital rebel prior to this and before that the sony 828. I had just great results with the canon rebel and i upgraded because i take alot of sports shots and the quick 5fps was an attraction to me. It's my gut reaction having had around 6 digicams since 1998 that either somethings just not right or when i sent it back to have the pop up flash fixed (only having it two weeks) the shipping and handling which was so poor. The camera was bouncing all around the place in the box opon arrival that maybe the sensor or something got knocked out of alighment. jcarboski p.s. if you email me at jcarboski@yahoo.com i will email you back the orginal photo, not resized so you can read the exif settings.
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Old Dec 26, 2004, 8:27 AM   #7
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I got a look at the unedited original and learned some interesting things.

I have put the exif data at the end of this post.

It is a little soft, but not really badly so. Was this taken on a tripod? I'm guessing there is a little motion blur from it being hand held. The eyes are a bit softer than is preferred.

These comments are based on my 10D use... maybe this has improved in the 20D? The AF mode is "AI Focus". I never found this mode to be too useful. It always seemed to shift into AI Servo when I didn't want. In my experience it was better to use One Shot for stationary and AI Servo for moving subjects. I found that this lead to shots that were some times slightly OOF or with the focus not where I wanted.

But the thing that really caught my eye was which AF point was used. You can do the same thing I did. Load the image into the EOSViewer Utility that comes with the camera. Open the image and choose the 12th icon from the right (its tooltip says "AF point".) It will show you all the AF points and light up which was used. The top and center points are light up. There is a tradeoff when you have multiple AF points enabled at once. You let the camera choose which is the "right" one. But how does it know? Does it know better than you do? It can get it right (and when it does your life is easier) but it will also get it wrong... and you have no control over how it does. It's just luck and the skill of the engineers at Canon (and the tradeoffs they made in design.)

This doesn't always work, depending on the situation, but this is what I've found most people here do. The center AF point is better than the rest on the 20D. So people set the camera to use the center point only and recompose. This doesn't always work (if the subject moves too much, for example) but then you are in control and you understand when it will and won't work. This should lead to better results.

To make this shot work, I would edit it photo shop and sharpen the entire picture but also add more sharpening to the eyes. It might not get them as sharp as you want but it should help.


File Name
Camera Model
Canon EOS 20D
Shooting Date/Time
12/17/2004 7:33:42 AM
Shooting Mode
Tv( Shutter Speed )
Av( Aperture Value )
Metering Mode
Evaluative Metering
Exposure Compensation
ISO Speed
28.0 - 75.0 mm
Focal Length
54.0 mm
Image Size
Image Quality
Flash Type
External E-TTL
Flash Exposure Compensation
Red-eye Reduction
Shutter curtain sync
1st-curtain sync
White Balance Mode
AF Mode
AI Focus AF
Parameters Settings
Contrast Mid. High
Sharpness Mid. High
Color saturation Mid. High
Color tone 0
Color Space
Noise Reduction
File Size
1621 KB
Custom Function
<none are set>
Drive Mode
Single-frame shooting
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Old Dec 28, 2004, 1:52 AM   #8
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The 20D comes with an Adobe Element2.Try puttingyour son's picture thru with the following USM. Amount 75%, Radius 2 and Threshold 3. The picture is right on. try it. You'll know.
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Old Dec 29, 2004, 3:24 AM   #9
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Do what NatureNut says, I tried it on your pic and it makes a world of difference.

Thanks NatureNut, I tried those settings on some of my pics and it works really well.


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Old Dec 29, 2004, 6:28 AM   #10
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eric s wrote:
Open the image and choose the 12th icon from the right (its tooltip says "AF point".) It will show you all the AF points and light up which was used
I never knew that.

I had several photos that seems oddly out of focus. I can see why now.

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