[simico]

my point is that out of focus areas are much nicer with rounded blades.

The funny thing is: only the obsessed photographers (dare I say measurebators lol) care about that. When I show photos to normal people (i.e. non-photographers) they couldn't care less about these negligible technical differences. So I also don't care Interesting subject and the picture as a whole is far more important. Makes me more happy and leaves more money in my pocket

Each to his own, horses for courses, ymmv and all the usual disclaimer lol

[Rondec]

I actually am not an "obsessed" photographer. There are just certain things that pop out at me when I am looking at a photo and this happens to be one. I am not arguing that you can't take good photos with non-rounded lenses. I am not arguing that if you take a lousy lens formula and round the aperture blades that it will suddenly become better. I am only saying that with everything else being equal, I prefer the look of a lens with rounded aperture blades to one without.

But I'll let it go here. No need to beat a dead (or dying) horse.

[QFish]

I prefer the look of a lens with rounded aperture blades to one without.

If you do not print from the film PS is your best friend!

[ElJamoquio]

The funny thing is: only the obsessed photographers (dare I say measurebators lol) care about that. When I show photos to normal people (i.e. non-photographers) they couldn't care less about these negligible technical differences. So I also don't care Interesting subject and the picture as a whole is far more important. Makes me more happy and leaves more money in my pocket

Each to his own, horses for courses, ymmv and all the usual disclaimer lol

I agree with what you're saying - I have completely flawed pictures which other people love.

I hate them because my eyes are always drawn to what I consider the 'flaws'.

Would I pay an extra $20 to remove what distracts me? Sure.

[Anvh]

Laddie, in other words you've never actually used the 40 XS before and are quoting other people. Let me assure you that there is a difference small as it is. Please, you can hold on to your opinion that rounded aperture blades don't make a difference to your eyes but to mine and some others, there is definitely a discernible difference. Instead of quoting and linking to other people's images (did you have the courtesy to notify them first), I would suggest you actually use your own images to prove your arguments.

Then please show me a side by side comparison that shows a difference in the blur.
If you provide your DA40XS i'm more then happy to make a comparison.

About linking and quoting, all that i mention has been said or is displayed in public and link to someone his site is only beneficial for him, free advertisement.
And from the people i got the information, i've never mention them by name.



ps. funny you say something about asking permission to quote someone, i didn't receive anything from you asking if it's okay for you to quote me....

[Anvh]

You say this as though highlights in in out of focus areas are uncommon. They are quite frequent in most photography (other than studio photography).

Obviously, I have posted two completely different photos from lenses with completely different focal lengths, but my point is that out of focus areas are much nicer with rounded blades. Is it a make or break thing? Well, for me, yes. I hate hexagons or octagons popping up in the backgrounds of my photos. Others look at hexagons and say "what nice bokeh" and if they truly feel that way, then good for them.

But the shape of the highlight is NOT bokeh, you're free to say that you like rounded highlights better then then flat sided ones but don't say that this means your bokeh is better because that isn't the case and that's my point.

You actually seem to confirm with me that you can't see any difference when there isn't a highlight in the background and that's precisely my point, rounded blades does nothing for the blur and primarily only effect the highlight shapes.

[eddie1960]

But the shape of the highlight is NOT bokeh, you're free to say that you like rounded highlights better then then flat sided ones but don't say that this means your bokeh is better because that isn't the case and that's my point.

You actually seem to confirm with me that you can't see any difference when there isn't a highlight in the background and that's precisely my point, rounded blades does nothing for the blur.

your definition of Bokeh is too narrow, it includes the highlights - at least as far as wiki is concerned

from the wiki

also sometimes heard as play /ˈboʊkə/ BOH-kə,[2] Japanese: [boke]) is the blur,[3][4] or the aesthetic quality of the blur,[5][6][7] in out-of-focus areas of an image. Bokeh has been defined as "the way the lens renders out-of-focus points of light".[8] However, differences in lens aberrations and aperture shape cause some lens designs to blur the image in a way that is pleasing to the eye, while others produce blurring that is unpleasant or distracting—"good" and "bad" bokeh, respectively.[3] Bokeh occurs for parts of the scene that lie outside the depth of field. Photographers sometimes deliberately use a shallow focus technique to create images with prominent out-of-focus regions.

Bokeh is often most visible around small background highlights, such as specular reflections and light sources, which is why it is often associated with such areas.[3] However, bokeh is not limited to highlights; blur occurs in all out-of-focus regions of the image.

[creampuff]

Then please show me a side by side comparison that shows a difference in the blur.
If you provide your DA40XS i'm more then happy to make a comparison.

About linking and quoting, all that i mention has been said or is displayed in public and link to someone his site is only beneficial for him, free advertisement.

I think the onus is on you to prove your point since it is you who is making claims that rounded highlights isn't bokeh. Suffice to say my understanding of bokeh relates to the way a lens renders out-of-focus points of light and rounded aperture blades do make a difference small as they may be.

And btw, irrespective whether posting other people's images is beneficial or constitutes free advertising doesn't change the fact that you didn't even bother to seek permission or credit the person. Talk about bad form when you can't even come up comparative images of your own to back up your assertions.

[Rondec]

But the shape of the highlight is NOT bokeh, you're free to say that you like rounded highlights better then then flat sided ones but don't say that this means your bokeh is better because that isn't the case and that's my point.

You actually seem to confirm with me that you can't see any difference when there isn't a highlight in the background and that's precisely my point, rounded blades does nothing for the blur and primarily only effect the highlight shapes.

Maybe I should not use the word bokeh and instead use the more generic term "rendering of out of focus areas." Rendering of highlights is only one component of this, but depending on the image, it can be a large component.

[Anvh]

Maybe I should not use the word bokeh and instead use the more generic term "rendering of out of focus areas." Rendering of highlights is only one component of this, but depending on the image, it can be a large component.

Both are actually the same, the thing is you only see the rounded blades back in the highlights and not the blur.
Look at the samples linked to with the DFA100 and DFA100 WR, it's imposable to see a difference in the blur between both.
I'm really surprised creampuff say he can see a difference.

[Anvh]

your definition of Bokeh is too narrow, it includes the highlights - at least as far as wiki is concerned

from the wiki

Bokeh

Since any image is represented by a large number of images of points, we may attempt to understand the whole by considering the blurring of a single point. An unsharply imaged point is associated with a circle of confusion, or a blur disk. This blur disk is characterized by
- A size.
- A shape.
- The light distribution across the disk.

The size of the disk determines the "amount of blur". The shape of the blur patch does not need to be circular, in which case the designations "circle of confusion" or "blur disk" are misnomers. Nonetheless, for convenience the word disk will be freely used to mean a patch of arbitrary shape. Although the size and the shape of the disk are unmistakable blur characteristics, they do not touch the essence of bokeh as the Japanese intended the word. The distribution of light across the disk does. However, the distinction is not always clear and what follows is intended as an overview of a variety of factors that influence the rendering of OOF image parts. Explanations of the underlying mechanisms will be brief and the reader is referred to other pages for elaborateness.

About Bokeh

The rest of the misconceptions are right to a certain degree, but there is more to the story of “lens bokeh.” To start with, people who think that caring about Bokeh is just photographic elitism are slightly off base, in my opinion. It is true that people who do only wide sweeping landscape photography hardly need to worry about Bokeh-- the important thing for them is a lens that is razor sharp at higher apertures, and they usually don’t want ANYTHING out of focus. But with portrait pictures, flower pictures, macro pictures and when you want to make a subject really pop out of the picture, one will have a significant portion of the picture that is out of focus. Why would one think that this wide swath of film area doesn’t matter? A sharply focussed and busy background often detracts from the image, drawing your attention away from the subject (see the image on the introduction page for an example). An image with bad bokeh does the same, making a busy background out of what should have been smoothly rendered background that would make your subject stand out. Furthermore, the shape of aperture blades DOES make a difference to the bokeh of a picture, but only in that non-circular aperture blades will lead to non-circular highlight out of focus “circles.” This should mostly affect single specular points of light in the background, while the effect on solid shapes and lines should be minimal. There is far more to the quality of blurred areas in images than simply the circularity of the aperture blades. It also has to do with the path of light through the lens elements, how well corrected the spherical aberration is, as well as coma, curvature of field, astigmatism and a few other properties of lenses. At this time, I am focusing on Spherical aberration, since this appears to have probably the most effect on “lens bokeh.” As this site develops I may expand to other lens parameters which affect bokeh, as well.

http://www.zeiss.com/c12567a8003b8b6f/embedtitelintern/cln_35_bokeh_en/$file/cln35_bokeh_en.pdf

Sometimes the phenomenon of the individual iris images is equated with “bokeh’; under this heading one finds collections of pictures in which iris images are mixed with photos of soap bubbles. But this is not what is meant by “bokeh”. In the iris image the lens is reading the cards to a certain extent but what significance has all this for the reproduction of image areas in which there are no highlight areas?

There is a particularly interesting point further to the left in the graphic above, about 0.4 mm in front of the focal point of the paraxial rays: there, the marginal rays seem to overtake those travelling more on the inside. The light cone is no longer ideally arranged, and we could say that the rays of light are "confused."
This is the original meaning of the Japanese word "bokeh."

http://www.kenrockwell.com/tech/bokeh.htm

Diaphragm Blades

The shape and number of a lens' diaphragm blades has little to do with bokeh. They define the shape of the blur circle, but they don't define how the light is distributed within that circle. These circles are no longer circles, but shapes with as many sides as there are blades. For instance, with five blades as most Hasselblad and Mamiya lenses one gets five-sided pentagons as the shapes of out-of-focus highlights instead of circles. This isn't too great. With six blades, most common in discount lenses for 35mm SLRs, one gets hexagons. With seven blades (most Nikkor SLR lenses) things really start to improve, since the seven-sided heptagons start looking like circles instead of recognizable shapes. Nine blades (common on Nikkor telephotos) are great, and lately they are being designed with curved blades to give a close approximation of a circle.

Odd numbers of blades will give diffraction and reflection stars around very bright points of light that have double the number of points as the number of blades. For instance, a seven-blade diaphragm will give a lovely 14-pointed star. Even numbers of blades will give stars with the same number of points as you have blades. An eight-bladed diaphragm will give a boring eight pointed star.

Again, how well one approximates a circle is only a small part of the equation. The important part is how the light is distributed. Obviously at full aperture where most people worry about this the diaphragm plays no part.

The reason some manufacturers attempt to draw a correlation between bokeh and numbers of diaphragm blades is because it's easy to see how many blades there are at the sales counter, but almost impossible to see bokeh.

http://jtra.cz/stuff/essays/bokeh/

The character of bokeh is best observed on small light sources. This character is mainly given by optical construction of lens. Most of modern lenses have rounded aperture blades. Older straight aperture blades produced polygonal out of focus highlights (if aperture was slightly closed). While the aperture blades are rounded in current lenses they may still be slightly visible in some aperture settings. Sometimes a single blade is slightly misaligned and more visible than others. I have seen too often marketing claim "rounded aperture blades produce pleasing bokeh". But rounded aperture blades are not guarantee of pleasing bokeh.

I think the onus is on you to prove your point since it is you who is making claims that rounded highlights isn't bokeh. Suffice to say my understanding of bokeh relates to the way a lens renders out-of-focus points of light and rounded aperture blades do make a difference small as they may be.

And btw, irrespective whether posting other people's images is beneficial or constitutes free advertising doesn't change the fact that you didn't even bother to seek permission or credit the person. Talk about bad form when you can't even come up comparative images of your own to back up your assertions.

You can find explanation above as for the rest, we live in a society that you need to prove that something is, so rather that i need to prove that highlights isn't bokeh you need to prove it is.
Beside i've offered to do it if you or anyone else will borrow me their DA40XS, it's unreasonable for you to suggest i need to buy a DA40XS just to prove my point and since you have both the XS and the limited it's easier for you to prove you're right.

Like i said i'm happy to provide images if i've access to lenses that can be used for such a comparison.
And i linked to the person site, you can see his name, contact information and the rest of his photos there.
Really this goes about nothing, if you don't want that people see your images on the internet then don't put them there publicly.




ps. about bokeh and the blurriness you should really read the Carl Zeiss PDF, it has all the information.
http://www.zeiss.com/c12567a8003b8b6f/embedtitelintern/cln_35_bokeh_en/$file/cln35_bokeh_en.pdf

[RioRico]

Much of the above isn't really relevant. The spirit of the original Japanese (implying mental haze or senility) is irrelevant, since words shift meanings with usage. (Cf. 'gay'.) The common understanding is that bokeh is the rendering of out-of-focus areas in an image. ALL OOF areas. Since we're citing stuff, here's the start of the Wikipedia entry:

In photography, bokeh ... is the blur, or the aesthetic quality of the blur, in out-of-focus areas of an image. Bokeh has been defined as "the way the lens renders out-of-focus points of light". ... Bokeh occurs for parts of the scene that lie outside the depth of field. ... Bokeh is often most visible around small background highlights, such as specular reflections and light sources, which is why it is often associated with such areas. However, bokeh is not limited to highlights; blur occurs in all out-of-focus regions of the image.

Can we get back to the topic now? Pentax has apparently awakened on lens pricing. That is good. I can once again consider the DA21Ltd. All I need is money. Would anyone like to buy a hyperactive grandson? He is very bright. Just 19 months old, and he is reading! He'll likely be a valued contributer here in a couple years.

[Anvh]

Then why not call it OOF?
Besides the amount of text about this shows the original definition is still used, to be frank there seems to be a bridge between the two. When someone goes deeper into this matter they often refer to the original meaning of the word while the other meaning is used to simply mean everything not in focus and there it ends really, because when you approach this scientifically you are talking about the OOF. So the amount of understanding defines the meaning it seems.

Anyway we are talking about something aesthetic and that's something all accounts agree with, so there isn't good or bad or something necessarily better or worse to begin with.

[eddie1960]

Much of the above isn't really relevant. The spirit of the original Japanese (implying mental haze or senility) is irrelevant, since words shift meanings with usage. (Cf. 'gay'.) The common understanding is that bokeh is the rendering of out-of-focus areas in an image. ALL OOF areas. Since we're citing stuff, here's the start of the Wikipedia entry:



Can we get back to the topic now? .

nope



BTW i'm with you Rico, back on topic would be the prices have adjusted and the 40 xs is likely going to be just fine against the canon. there are plenty of reasons to get the LTD (build, quick shift, hood...) and it is now a more reasonable 369.95.
and Bokeh has many variants and can be interpreted many ways , I quoted the Wiki specifically because it is generally a widely accepted view, just not anvh's apparently
too each his own. Personally like rondec I like the circular blades, and like lowell i would be interested in seeing how they deal with lights at night (ie starbursts)

[Anvh]

Wikipedia is fine for some things but you can never use it as reference you know.

Sometimes the Dutch wiki does not even agree with the English wiki for example, go figure