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11-12-2011, 08:58 AM   #16
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I think there is more a tyranny of noise (lack of it to be precise) more than a tyranny of in focus.

11-12-2011, 10:44 AM   #17
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QuoteOriginally posted by newarts Quote
Some of us are more subject oriented than others. I like full face portraits, macros where the subject dominates the photo, etc - in many of my photos edge sharpness doesn't matter or can detract from my purpose.

A good case in point is the use of the Raynox close-up lens for macros; here's a nice macro posted here recently by Beregeded:

https://www.pentaxforums.com/forums/lens-clubs/74221-raynox-macro-club-23.html#post1709155

Looks great to me! But here's a test showing the edge sharpness for a Raynox 150 on a good Macro lens (Tamron 90:2.5):

Without the Raynox 150, the edges of the photo are just as sharp as the center. with the Raynox the edges and corners are poor. The top-most of the crops shows the upper-left quadrant of the full photo... Notice the in-focus area is in a disk about equal to the frame height.

But this is the sharpness distribution for the lens used to take the macro posted above - clearly the edge softness inherent in using the Raynox had no practical effect.

Edge quality matters a lot for wide angle lenses - one of the main reasons to use a wide angle lens is to see what's at the edges of a scene - otherwise why use a wide angle lens?
I've actually been shooting my LCD screen quite a bit recently. For some reason it seems a good way to test different macro configuration (lens reversing and such). I guess it's because it emits light and requires a shorter shutter speed than some things. Anyway, I can say that it's often difficult to get the entire FoV in focus, you have to have your front element exactly parallel to the screen, the barrel of the lens exactly perpendicular, you get funky diffraction issues that look really similar to what you posted. It's caused by the way LCDs are made, and the layer of protective glass over them. I'm not sure it makes for the best subject for testing edge to edge sharpness, unless you know this going in and are extremely careful to keep shooting tests until you get your camera perfectly aligned with the front of the screen.

Offtopic, but related in a way, here's a 1:1 crop of a 5:1 shot of a single LCD monitor pixel. Not quite as sharp as I want, I'll try it again sometime, but still kinda cool.

11-12-2011, 06:54 PM   #18
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QuoteOriginally posted by pop4 Quote
Might I suggest the OP have a look at the https://www.pentaxforums.com/forums/mini-challenges-games-photo-stories/93874...our-bokeh.html thread? Not everyone's obsessed about edge-to-edge shallow-to-deep focus!
I didn't respond earlier because i was on travel, but looking at the thread tonight - its great!!! thanks for the link.
11-13-2011, 03:23 PM   #19
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There is an important balance to be struck between sharpness and bokeh, both of which i think are overrated.

Sharpness is useful for pop and detail retention but more detail does not equal better photo. Often you want to isolate, and isolation should trump sharpness (sometimes a subject's ears will be out of focus - this is OK).

Bokeh can be incredibly distracting, but the photos you posted are examples of good bokeh. The problem is more when you have some subject and then big swirls in the background, a blurry mess.

Sometimes this mess can overtake the subject in salience, and i personally think this makes for bad photography.

Even with fast aperture lenses like the FA 50 / 43. I tend to think the sweet spot is around 2.5-3.2. Which is why the DA ltds are pretty cool - how often are you going to shoot wide open and get optimal (i.e., not special-effecty) shots? 2.8 constant aperture zooms are often the pro's tool of choice because the flexibility of a zoom far outshines a prime's corner sharpness of preposterously thin DOF control.

11-13-2011, 06:27 PM   #20
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QuoteOriginally posted by paperbag846 Quote
There is an important balance to be struck between sharpness and bokeh, both of which i think are overrated.

Sharpness is useful for pop and detail retention but more detail does not equal better photo. Often you want to isolate, and isolation should trump sharpness (sometimes a subject's ears will be out of focus - this is OK).

Bokeh can be incredibly distracting, but the photos you posted are examples of good bokeh. The problem is more when you have some subject and then big swirls in the background, a blurry mess.

Sometimes this mess can overtake the subject in salience, and i personally think this makes for bad photography.

Even with fast aperture lenses like the FA 50 / 43. I tend to think the sweet spot is around 2.5-3.2. Which is why the DA ltds are pretty cool - how often are you going to shoot wide open and get optimal (i.e., not special-effecty) shots? 2.8 constant aperture zooms are often the pro's tool of choice because the flexibility of a zoom far outshines a prime's corner sharpness of preposterously thin DOF control.
Thank you for discussing this, this is the kind of information i was hoping to see. I had come to my own conclusion that a certain amount of blurring could help tell a story, but it hadn't occurred to me that too much bokeh could actually detract from the subject. When one's eyes are focused on an object, the peripheral vision is naturally not as sharp as the center vision area. The first shot i provided came out of a request by a theatre director to take "general ambience" shots of the audition process for upcoming plays. The tumbler full of pencils seemed to me iconic of the information exchange process and the blurred people in the background are part of the process. I don't know which of the 30 photos i turned will get used, but the point is, the bokeh can help tell a story. A second example is the type of picture where there is diagonal row of similar objects in profile. The shallow focus area hilights one of the objects, while the subsequent and prior ones meet with increasing amounts of blurriness - but they help to tell the story.
11-13-2011, 07:34 PM   #21
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FWIW i rarely shoot smaller than f/2.
I love shallow dof and isolating subjects, as for sharpness ,there are plenty of lenses out there that are very sharp from f/1.4 , so you can have the best of both worlds (sharp and shallow DOF)
11-14-2011, 01:26 AM   #22
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QuoteOriginally posted by Wheatfield Quote
I think there is more a tyranny of noise (lack of it to be precise) more than a tyranny of in focus.
I couldn't agree more!

- and then I would add the tyranny of "sharpness". (Not to be confused with in-focus).

Since sharpening in post-processing has become so easy, one often feels that good images are only those that are so "sharp" that they will cut a hole in your retina.
11-14-2011, 06:03 AM   #23
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QuoteOriginally posted by Wheatfield Quote
I think there is more a tyranny of noise (lack of it to be precise) more than a tyranny of in focus.
If anything, the tyranny is an obsession with the attributes of an image rather than its content. Just as "everything has to be sharp" gets taken to its extremes and beyond, so does "it has to have BOKEH" where suddenly an image has some inherent quality just because the depth of field is shallow. You know, snap a shot of a computer keyboard at an angle and wide open and OOHH LOOOK MOST OF THE KEYS ARE BLURRED WHOA and the bokeh-obsessed photographer is convinced he has created a masterpiece when such a crap image is a crap image no matter the lens, camera, processing or depth of field.

The obsession with taking pictures in a "certain way" has a tendency to end up with both the photographer and viewer overlooking the content of the image. So we end up with turds rolled in glitter, turds polished like expensive shoes, turds spraypainted day-glo yellow, turds in every fanciful arrangement imaginable, and nobody seems to notice they are just looking at a giant pile of shit.

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