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Not Bad For f20

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ozdean

ozdean

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18-135 @ 40 & 135





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Regards Dean - Capturing Creation
 
Thanks Chris.
--
Regards Dean - Capturing Creation
 
Nice shots. There is nothing to be afraid of when stepping down to f11-22. In fact, i found that range is necessary with macro shots if i want to achieve overall sharpness. Also great for landscapes.

Is there diffraction taking place? Probably, but does it matter, no. It may when you start comparing side by side images at 100% crop. But unless you provide those comparisons, no one will ever know. And comparing 100% crops is not a way to enjoy photography.

Print those shots at f11 and f22 and the average person will see the image and not the technical affects of those apertures.

Use whatever aperture you need to achieve the DOF you require.

Happy shooting.
 
Thanks Mahesh
--
Regards Dean - Capturing Creation
 
So true Adrian.
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Regards Dean - Capturing Creation
 
Agreed. The whole notion that apertures beyond f11 will "ruin" photos is ridiculous. It's true that softness increases beyond a certain point but it's not the demon that some make it. In much of my photography I live at f11 through f22, and have recently discovered the joys of f19;> )

Nice and needed thread. Thanks.

Cheers. ernie
 
Thanks CD
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Regards Dean - Capturing Creation
 
Thanks Ernie, and yes there is this diffraction fear around.
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Regards Dean - Capturing Creation
 
You need at least 2000 pixels wide image to start seeing diffraction effects at f/22 on an 1.5x crop camera, so in this size it's nowhere near. Even theoretically.

Nice shots, BTW!
--
Ilkka V
 
For any given f-Number, it's possible to have a resolution requirement that's low enough, and/or an enlargement factor that's small enough, and/or a viewing distance that's great enough to permit the use of even the smallest apertures (largest f-Numbers) available on your lens.

The degradation caused by diffraction is not a problem until the Airy disks are large enough in the final print, after enlargement, to inhibit your personal goal for print resolution at an anticipated viewing distance.

Here's a formula for determining the aperture, f/N, at which diffraction's Airy disks will only just begin to inhibit your desired print resolution at the anticipated enlargement factor:

N = 1 / enlargement factor / desired print resolution / 0.00135383

So, if you know your desired print resolution (3 lp/mm, for example) and how much larger the diagonal of your final print will be than your sensor diagonal, you can use this formula to calculate the f-Number at which diffraction will begin to inhibit your desired print resolution.

If enlargement factor or desired print resolution are small enough, the f-Number at which diffraction will begin to inhibit your desired print resolution might be f/16, f22, or even a larger f-Number that's not available on your lens.

It's ridiculous the way so many people will dictate that a given f/Number will "cause diffraction" for this camera or that - without QUALIFYING their statement with specification of the anticipated enlargement factor and desired print resolution (which itself must accommodate an anticipated viewing distance).

For more, read these five posts (or the entire thread) from the Canon Digital Photography Forum:

http://photography-on-the.net/...orum/showpost.php?p=2756604&postcount=25
http://photography-on-the.net/...orum/showpost.php?p=2780643&postcount=39
http://photography-on-the.net/...orum/showpost.php?p=2784205&postcount=45
http://photography-on-the.net/...orum/showpost.php?p=2786373&postcount=54
http://photography-on-the.net/...orum/showpost.php?p=2788383&postcount=57

The complete thread starts here:
http://photography-on-the.net/forum/showthread.php?t=279951

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Mike Davis
http://www.AccessZ.com
 
Uugh......thanks for the good info, but it looks like back to MF to make decent sized landscape wall print :(
 
It all depends on what resolution you hope to achieve in the final print and that depends, in part, on your anticipated viewing distance. (Highway billboards can look great at 100 yards...)

The vast majority of photographers are unknowingly content with amazingly low resolution, but high acutance prints.

For an explanation of the difference between resolution and acutance, see Sean McHugh's tutorial on sharpness:

http://www.cambridgeincolour.com/tutorials/sharpness.htm

Consider this: Even with a camera like the 16.61 MP Canon EOS 1Ds Mark II, the 4992 x 3328 pixel capture, when put to paper at 360 ppi without resampling (which is equivalent to a print resolution of 5 lp/mm when taking into account resolution lost to Bayer algorithm and AA filter), will only yield a 9.24 x 13.87-inch print.

9.244 inches * 360 ppi = 3328 pixels
13.866 inches * 360 ppi = 4992 pixels

So anyone out there who's routinely making 360 dpi 9x13-inch prints (without cropping) from a 16.61 MP sensor is limited to a maximum print resolution of 5 lp/mm, but a young adult with healthy vision can appreciate resolutions as high as 8 lp/mm when viewed at a distance of 25cm (9.84 inches) - and some experts, like Ctein (if he deserves that designation), would argue that even higher resolutions can be distinguished by the naked eye.

We could make "sharp" 20 x 30-inch prints from a 16.61 MP sensor, but they'll be "sharp" only by way of acutance (edge sharpness), not by way of resolution (fine subject detail), because at 20 x 30, the actual subject detail will be diluted to something less than 2.5 lp/mm (less than half the resolution enjoyed in a 9.24 x 13.87-inch print from 16.61 MP).

But that's perfectly OK as long as your audience stands twice as far away from the print that's twice as large.

In other words, your "desired print resolution" can be cut in half when you're willing to assume that your audience will view the print at a distance of 20-inches instead of 10-inches.

It amazes me how few people in photography forums are willing to declare, or even consider, their anticipated enlargement factor, desired print resolution (and the latter variable's dependency on viewing distance) when discussing factors that affect "sharpness".

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Mike Davis
http://www.AccessZ.com
 
Very good perspective Mike.....Thanks.

Just struggling to get back to where I was 15 years ago.....making 16x20 Cibachromes (actuallly 14.5x20s full negative) from 645 Velvia slides. :)

DSLRs have been a "start from the beginning again" experience......

Regards, Larry
 
Larry,

Wow, you paid your dues and then some working with such large Cibachromes.

A lot of people today would be amazed just how much subject detail can be extracted from an MF Velvia chrome - and even at that enlargement factor, grain wasn't an issue with Velvia.

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Mike Davis
http://www.AccessZ.com
 
I just picked up Bryan Peterson's new edition of "Understanding Exposure" and in response to this area of discussion, he has a 200% crop of 2 images, 1 at f9, 1 at f/22, and the difference is so negligable even at that magnification.
eadrian75 said:
Nice shots. There is nothing to be afraid of when stepping down to f11-22. In fact, i found that range is necessary with macro shots if i want to achieve overall sharpness. Also great for landscapes.

Is there diffraction taking place? Probably, but does it matter, no. It may when you start comparing side by side images at 100% crop. But unless you provide those comparisons, no one will ever know. And comparing 100% crops is not a way to enjoy photography.

Print those shots at f11 and f22 and the average person will see the image and not the technical affects of those apertures.

Use whatever aperture you need to achieve the DOF you require.

Happy shooting.
Click to expand...
 
impressive detail and color.

rene
 
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