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Old Apr 4, 2010, 2:42 AM   #11
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For most people using a dSLR this is the wrong approach. The advantage of a dSLR is the clean photos produced over a P&S, if you start going above the standard settings then you will lose some of this advantage by bringing in noise from sharpening, and adding colour etc that you can't remove later. It is better to leave things basic and then do all adjustments in PP, the cameras processing is nowhere near as good as that of software on the PC so don't hinder yourself to start with.

I personally lower sharpness one step further from standard to help even more with reducing noise.
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Old Apr 4, 2010, 11:13 AM   #12
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For someone that is not a big PP, it is just another tool one can use. I think that is why canon put it into the camera.
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Old Apr 4, 2010, 12:11 PM   #13
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Sharpening is only really important when printing or posting to the web, any time you present a photo basically. When doing this you have to use PP and best to make sharpening the last action. Yes it can be done in camera but not as well and too early in the process to be the optimum.

Yes Canon and other manufacturers allow you to sharpen a lot but I wouldn't.

Each can make their own choice for what is best.
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Old Apr 4, 2010, 9:01 PM   #14
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Good Evening HeavyBird,

I tend to do the vast majority of my shooting in the early evening and at night since I work during the day. I have also cobbled together a technique that works very well, and I think will answer most of your questions.

To get maximum sharpness I swing by some of the published lens tests, and take a look at their results. To cut to the chase, for the most part, lenses are their sharpest at around f5.6 to f8 and sometimes out to f11. However, as an example, I'll use the Canon EF 50mm f1.8 II lens (since you are asking about a Canon camera).

http://www.dpreview.com/lensreviews/..._c16/page3.asp

Go to the above website and take a look at the graph. Use your mouse to grab the aperture window and move it around. The color of the graph will change. Move it back and forth until you get the greatest amount of blue. It should be around f5.6.

You can also go to ...

http://www.photozone.de/canon-eos/16...review?start=1

Scroll down to MTF (resolution & chromatic aberrations) section of the write up. You will see a set of histograms and move along until you see where both the center bar (blue) and edge bar (purple) is at a maximum, or reasonably high together at the same time. It is again f5.6, although f8 is not bad at all (it is wonderful when lens reviews agree).

So for this lens f5.6 appears to be pretty close to the best you can get. Now, in your book they are talking about f11, f16 on up to f22+. Well there is the law of diminishing returns, and it works in optics too (even though my optical engineering class was 40 years ago). Once you reach an optimal resolution, sharpness drops off as the aperture get smaller. This is due to diffraction. As the aperture (the hole the light passes through) gets smaller, it essentially forces the light to spread out, rather than focusing it to a point. Take a look at this website for additional descriptions.

http://www.earthboundlight.com/photo...apertures.html

So, what do you do if you can't find any information on your lens - use f5.6 to f8 if its 50mm or below in focal length. If its above 50mm - say 100mm use f8, and if its in the 200+ use f11 as a rule of thumb. Telephoto lenses have smaller apertures, so that is why the optimal aperture tends to rise with focal length.

Ok, so going back to the canon lens - we have f5.6 that we want to use. How about focusing? Do you want a shallow depth of field or do you want as much as possible in focus? Let's take as much as possible in focus, since you are concerned with sharpness. Go to the depth of field calculator. Enter the focal length - 50mm, select the f value 5.6 from the pull down, select the camera type up at the top. Also enter the approximate distance to what you are photographing.

You will notice that down at the bottom there is a value for hyperfocal distance. Well that is the distance that you want to set your camera to (approximately), and its 75 feet - so let's say in your picture that the building was about 75 feet away. What that means is that everything from about 60 feet to infinity will be in focus. Also, over on the left hand margin there is a selection for "hyperfocal chart", third one down from the top. You can make your own charts and print them out, if you wish.

Set your camera up on the tripod, dial in f5.6 and 75 feet, select mirror up. I also select ISO 100 for the best resolution and low noise. Let the camera tell you the shutter speed, select mirror up and take the shot.

hope that helps...

I took this image using the same approach...

... well actually its 30 images stitched together as 2 rows of 15 each, but I also have the same photo using a 12-24 lens. (note, the original is 14,000 by 7,000 pixels, and I see the reduction really munches up the clarity. I have some others that are not reduced so much. I went to multiple rows to get additional sky and real estate below the house at the bottom of the image so as to frame it better. This, for want of something better is my lab that I use. Its about a 5 minute drive from the house and there is always a great sunset and valley lights to practice with.)

Take a look at these threads for some additional views,

http://forums.steves-digicams.com/pentax-samsung-dslr/163347-night-panorama.html
http://forums.steves-digicams.com/pentax-samsung-dslr/162509-unfair-comparison.html
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Last edited by interested_observer; Apr 4, 2010 at 9:27 PM.
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Old Apr 5, 2010, 6:25 PM   #15
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Originally Posted by interested_observer View Post
Good Evening HeavyBird,

I tend to do the vast majority of my shooting in the early evening and at night since I work during the day. I have also cobbled together a technique that works very well, and I think will answer most of your questions.

To get maximum sharpness I swing by some of the published lens tests, and take a look at their results. To cut to the chase, for the most part, lenses are their sharpest at around f5.6 to f8 and sometimes out to f11. However, as an example, I'll use the Canon EF 50mm f1.8 II lens (since you are asking about a Canon camera).

http://www.dpreview.com/lensreviews/..._c16/page3.asp

Go to the above website and take a look at the graph. Use your mouse to grab the aperture window and move it around. The color of the graph will change. Move it back and forth until you get the greatest amount of blue. It should be around f5.6.

You can also go to ...

http://www.photozone.de/canon-eos/16...review?start=1

Scroll down to MTF (resolution & chromatic aberrations) section of the write up. You will see a set of histograms and move along until you see where both the center bar (blue) and edge bar (purple) is at a maximum, or reasonably high together at the same time. It is again f5.6, although f8 is not bad at all (it is wonderful when lens reviews agree).

So for this lens f5.6 appears to be pretty close to the best you can get. Now, in your book they are talking about f11, f16 on up to f22+. Well there is the law of diminishing returns, and it works in optics too (even though my optical engineering class was 40 years ago). Once you reach an optimal resolution, sharpness drops off as the aperture get smaller. This is due to diffraction. As the aperture (the hole the light passes through) gets smaller, it essentially forces the light to spread out, rather than focusing it to a point. Take a look at this website for additional descriptions.

http://www.earthboundlight.com/photo...apertures.html

So, what do you do if you can't find any information on your lens - use f5.6 to f8 if its 50mm or below in focal length. If its above 50mm - say 100mm use f8, and if its in the 200+ use f11 as a rule of thumb. Telephoto lenses have smaller apertures, so that is why the optimal aperture tends to rise with focal length.

Ok, so going back to the canon lens - we have f5.6 that we want to use. How about focusing? Do you want a shallow depth of field or do you want as much as possible in focus? Let's take as much as possible in focus, since you are concerned with sharpness. Go to the depth of field calculator. Enter the focal length - 50mm, select the f value 5.6 from the pull down, select the camera type up at the top. Also enter the approximate distance to what you are photographing.

You will notice that down at the bottom there is a value for hyperfocal distance. Well that is the distance that you want to set your camera to (approximately), and its 75 feet - so let's say in your picture that the building was about 75 feet away. What that means is that everything from about 60 feet to infinity will be in focus. Also, over on the left hand margin there is a selection for "hyperfocal chart", third one down from the top. You can make your own charts and print them out, if you wish.

Set your camera up on the tripod, dial in f5.6 and 75 feet, select mirror up. I also select ISO 100 for the best resolution and low noise. Let the camera tell you the shutter speed, select mirror up and take the shot.

hope that helps...

I took this image using the same approach...

... well actually its 30 images stitched together as 2 rows of 15 each, but I also have the same photo using a 12-24 lens. (note, the original is 14,000 by 7,000 pixels, and I see the reduction really munches up the clarity. I have some others that are not reduced so much. I went to multiple rows to get additional sky and real estate below the house at the bottom of the image so as to frame it better. This, for want of something better is my lab that I use. Its about a 5 minute drive from the house and there is always a great sunset and valley lights to practice with.)

Take a look at these threads for some additional views,

http://forums.steves-digicams.com/pentax-samsung-dslr/163347-night-panorama.html
http://forums.steves-digicams.com/pentax-samsung-dslr/162509-unfair-comparison.html

But when you use a large aperture doesn't the light bounch around causing things to get blurry, the opposite of diffraction. At least that's what the book says.

Im just a bit confused, because some people say f8-f11 or even f16 for sharp landscape shots, while others say f5.6 or so. Wouldn't using a large appature, cause a shallow depth of field?
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Old Apr 5, 2010, 6:26 PM   #16
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Quote:
Originally Posted by Mark1616 View Post
For most people using a dSLR this is the wrong approach. The advantage of a dSLR is the clean photos produced over a P&S, if you start going above the standard settings then you will lose some of this advantage by bringing in noise from sharpening, and adding colour etc that you can't remove later. It is better to leave things basic and then do all adjustments in PP, the cameras processing is nowhere near as good as that of software on the PC so don't hinder yourself to start with.

I personally lower sharpness one step further from standard to help even more with reducing noise.
What is PP? Also is it best just to use a neutral setting on the camera? I can always sharpen afterwards.
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Old Apr 5, 2010, 6:33 PM   #17
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PP = post production editing, using photoshop, aperture or what ever editing software you have.
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Old Apr 5, 2010, 7:59 PM   #18
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Quote:
Originally Posted by HeavyBird View Post
But when you use a large aperture doesn't the light bounch around causing things to get blurry, the opposite of diffraction. At least that's what the book says.

Im just a bit confused, because some people say f8-f11 or even f16 for sharp landscape shots, while others say f5.6 or so. Wouldn't using a large appature, cause a shallow depth of field?
Most lenses are at their sharpest when stopped down a couple stops from largest aperture. It is due to the way lenses are designed. Light bouncing around (I take it this means internally) can sometimes be an issue at large apertures when there is a strong light source in the scene. It will sometimes cause 'ghosts' visible in the picture. This is more often a problem with : 1. point and shoot cameras 2. long zoom lenses. Less of problem with single focal length (prime) lenses with DSLRs. Fewer optical elements, and better anti-reflective coatings are the reason.

Depth of field is relative to aperture, focal length and focus distance. Landscape shots are usually taken at long focus distances, so unless there are foreground elements which you want to have in focus, small apertures aren't that necessary. The wider the angle of the lens you are using, the greater the DOF also. Someone will likely post a link to DoFmaster, which is a calculator, if you are interested in precise figures. I just wing it, but that is mostly due to enough experience to have a pretty good idea what the results will be.

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Old Apr 7, 2010, 1:51 PM   #19
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Are you talking about Bryan Peterson's Understanding Exposure book? I don't think he's meaning the light bouncing around literally (which causes ghosting as Brian pointed out), but rather figuratively to explain depth of field. He sometimes uses analogy to explain things (like his workers building houses to explain noise) and I thought that was his way of trying to explain it.
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Old Apr 7, 2010, 8:26 PM   #20
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Ah, the light dawns (OK, pun intended). The reference is probably to dispersion, as the opposite of diffraction. This is one of the reasons for stopping down a bit. Wide open, the lens uses all of the glass, whereas, when stopped down, the narrower aperture blocks light from the outer part. This usually results in increased sharpness.
To find out where a lens is sharpest, check out reviews with MTF results included. Some lens makers also have these graphs or charts for their lenses.

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