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12-28-2008, 05:27 PM   #1
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How to take pictures that are sharp throughout ?

How is this achieved ? Is it just infinity focus ? f8 cannot explain the whole thing?

Jay in the motel garden photo - Jay Rounds photos at pbase.com

How is the guy in the foreground so clear, and so is the whole image. How to exactly know where to focsu the camera ?

DOF calculator will show the circle of confusion as to what area in front and behind the image will be in focus, but how exactly does one approximate where to aim. Any short cut way...I am not talking about hyperfocal and approximating along 1/3rd of the frame...I think this is different.

12-28-2008, 05:39 PM   #2
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f8

21mm

sunny day

small photo (the user opted to not supply with full rez images)

i'm not surprised at all, perceived sharpness is increased when images are sized small with a good program.
12-28-2008, 05:56 PM   #3
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I am pretty sure it is not tach sharp, but I am trying to learn from this example, which seems to be sharp. If I were to focus on the man in the front, then the background will be blurry.

Online Depth of Field Calculator

Using this, at f8, if I were to focus at 10 feet distance then I will achieve infinity focus, so should I focus at 10 feet to get max DOF. It also says that objects within 4.77 feet will be blurry.

In the following images, is it just a matter of figuring what minimum focus distance at each aperture will give infinity focus?

Endless stairs photo - Joe Barnhart photos at pbase.com


Take my picture photo - Joe Barnhart photos at pbase.com


For these images at f5.6, focus at 13 feet to get infinity focus and accept the near objects within 6.46 feet will be out of focus.

Is this the way to look at getting the most of the scene in focus. Thanks.
12-28-2008, 08:30 PM   #4
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There is no guarantee that the image isn't cropped. He has used very good hyperfocal distancing for his picture, and may have cropped it somewhat. It is also a nice contrasty scene, which never hurts for percieved sharpness. All that and a deadly sharp lens.

12-29-2008, 05:11 AM   #5
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I can't get any exif here, so it might have been taken with a P&S camera. With the tiny sensor, DOF is huge.
12-29-2008, 05:14 AM   #6
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These are all taken with the Pentax DA 21mm/3.2 limited. I'll recieve this tomorrow, and thus my curiosity.

P.S: At the bottom of the image, towards the left end of it, it says 'full exif', you can press on that to get the EXIF info. All 3 images have it.
12-29-2008, 05:14 AM   #7
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QuoteOriginally posted by pcarfan Quote
I am not talking about hyperfocal and approximating along 1/3rd of the frame...I think this is different.
Why would you think that? Not being confrontative, just asking. As far as I know, this type of result is exactly what hyperfocusing with a smallish aperture would give you.
12-29-2008, 05:35 AM   #8
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QuoteOriginally posted by Erik Quote
Why would you think that? Not being confrontative, just asking. As far as I know, this type of result is exactly what hyperfocusing with a smallish aperture would give you.

I guess what I mean is...there is the DOF calculator, which tells you how much of the area in front and behind the image will be in focus.

Then there is the hyperfocal distance calculator.

I guee my question is, how are they related, which ones to use to get an image sharp from foreground to background.

Do, I use the DOF calculator and see where I focus to get the image sharp throughout (I assume this is at infinity focus, as when the calculator tells you 'infinity' for the area, that is in focus behind the focus plane) ?

or

Do I use the hyperfocal calculation to get the sharp image.

Which of the two ?, (or do both of these give the same result, ie when the dof calulation gives infinity focus that is hyperfocal distance ?)

or are there any other ways than these two?

Thanks

12-29-2008, 06:02 AM   #9
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f8 all the way. A compact camera with f8 would do the trick as well.
12-29-2008, 06:04 AM   #10
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Use the hyperfocal focus calculation at the bottom. It works but you have to measure the correct focusing distances with tape if you are using a zoom lens. The distance scales on those seem to fail with hyperfocal shots. I managed to do hyperfocal shots with M50 1.7 lens just fine with the scale on the lens. But it's far easier because it has the aperture markings. Just put the infinity distance at the selected aperture marking and you are set.
12-29-2008, 06:17 AM   #11
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Hi,

Besides all the good advise, there is another way to achieve unlimited focus pictures.

There are software solutions available that can help you to create what you want. Most similar like HDR (High Dynamic Range) photos you take multiple pictures of your object with multiple focus settings. The software combines it in 1 simple picture with possibly infinite focus sharpness.

Check this out: Helicon Soft: Helicon Focus
Or, if you own a Canon point and shoot, you could get add on firmware (at your own risk) to do this in camera: Samples: Unlimited DOF - CHDK Wiki

Of course you can allways close your diafragma and hope for the best.

Have fun,

- Bert
12-29-2008, 08:16 AM   #12
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Another view..

QuoteOriginally posted by pcarfan Quote
How is the guy in the foreground so clear, and so is the whole image. How to exactly know where to focsu the camera .
Have a look at this article. Basically, focus at the things in the background you need to be sharp. The aperture decides what in the foreground will be acceptably sharp.
12-29-2008, 09:14 AM   #13
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QuoteOriginally posted by bymy141 Quote
Hi,

Besides all the good advise, there is another way to achieve unlimited focus pictures.

There are software solutions available that can help you to create what you want. Most similar like HDR (High Dynamic Range) photos you take multiple pictures of your object with multiple focus settings. The software combines it in 1 simple picture with possibly infinite focus sharpness.

Check this out: Helicon Soft: Helicon Focus
Or, if you own a Canon point and shoot, you could get add on firmware (at your own risk) to do this in camera: Samples: Unlimited DOF - CHDK Wiki

Of course you can allways close your diafragma and hope for the best.

Have fun,

- Bert
Better advice would be to go out and take some pictures and learn by doing. It costs nothing but time, and then you have hard knowledge about how depth of field works rather than second hand knowledge gleaned from an internet source which may or may not be reliable.
Focus stacking, while a useful tool in some circumstances, is not a useful tool at all most of the time.
Stopping down and hoping for the best is, at best, not very smart.
12-29-2008, 11:04 AM   #14
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QuoteOriginally posted by pcarfan Quote
I guess what I mean is...there is the DOF calculator, which tells you how much of the area in front and behind the image will be in focus.

Then there is the hyperfocal distance calculator.

I guee my question is, how are they related, which ones to use to get an image sharp from foreground to background.

Do, I use the DOF calculator and see where I focus to get the image sharp throughout (I assume this is at infinity focus, as when the calculator tells you 'infinity' for the area, that is in focus behind the focus plane) ?

or

Do I use the hyperfocal calculation to get the sharp image.

Which of the two ?, (or do both of these give the same result, ie when the dof calulation gives infinity focus that is hyperfocal distance ?)

or are there any other ways than these two?

Thanks
You technically use the hyperfocal distance as that gives you the biggest DOF possible for a given focal length and aperture. The hyperfocal distance will be the closest focus distance that gives the far end of the depth of field to infinity. Play with those depth of field calculators to see how it works. Additionally, the smaller the aperture the more that will be in focus when at the hyperfocal distance.

On a recent trip, I took a shot of my wife and her best friend. They were both within the hyperfocal distance with a lighthouse 2 miles behind them (click here). I actually focused on them rather than the hyperfocal distance because it was important to me that they were sharp. The lighthouse while beyond the depth of field, still turned out quite sharp because it was close, because there was a decent amount of contrast, and because we only made a 5 x 7 print.

If I pixel peep I can see that the lighthouse isn't too sharp in the distance, and I am sure it would be more apparent if I made a bigger print. It is also important to note the focal length of the lens and the fact that my wife and her friend were a good 100 feet from me when I took the photo. Cropping and zoom can often distort the apparent depth of field.
12-29-2008, 02:28 PM   #15
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A good wide prime lens @ f8 would give a huge zone of "apparently sharp focus", well good enough for most folk anyway.

Try not to get to "wrapped around the axle" here, enjoy your photography.

Last edited by Kerrowdown; 12-29-2008 at 05:42 PM.
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