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01-09-2008, 10:45 AM   #31
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QuoteOriginally posted by Nesster Quote
AHA! I'd noticed similar changes when I used the Takumar 50/1.4 with extension tube + 2x converter. Changed the flavor of the bokeh, for the better.

But about that front bokeh, maybe the tc has the effect of changing the optimization point of the lens...
Yup, I'm sure it does. Off-the-cuff I would say that it is undercorrecting for spherical aberrations with the TC, but overcorrecting without.

This is exactly what the Nikon Defocus Control lenses do. If you search for more info on them, they are fascinating lenses - but not as fascinating as the Minolta STF.

01-09-2008, 11:36 AM   #32
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QuoteOriginally posted by carpents Quote
the Minolta STF.
Yeah!
That is truly amazing.
Such a lens from Pentax!
01-09-2008, 01:21 PM   #33
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Hi everybody!

I found my old password for the forum and can't resist jumping in.

Carpents mentioned this thread to me. I'm glad he did as I learned a few things from it.

Part 1:
Bokeh, or boke, is derived from Japanese and one of the stories about the word is about a certain style some Japanese painters used to paint fuzzy backgrounds in a manner reminding about the impressionism (you know Chagall and his water-lilies) and their way of just pressing the tip of the brush against the canvas. Those parts of the painting are not sharp but merely there to let the beholder emphasis on the sharp parts and at the same time make for a context.

That story suits me fine, it makes the word understandable. The spelling is not important. It started, in Englsih, as boke. The h was added pretty quickly as it helps with the pronounciation. I don't think there is "right" or "wrong" way to translate phonetic Japanese to English letters. Or maybe there is (I'm neither Japanese nor English -spoken)? Anyway, the most common way to spell bokeh is bokeh. The word is confusing as it is so why not use the most common way to spell it.

When using the word bokeh it replaces the whole phrase "quality of the out of focus parts of the picture". For example:

The bokeh is good = The quality of the out of focus parts of the picture is good.

or
What do you think about the bokeh? = What do you think about the quality of the out of focus parts of the picture?

Not like this:
There is a lot of bokeh in this picture = There is a lot of quality of the out of focus parts of the picture in this picture.

And not like this:
The DOF is thin, then the bokeh kicks in. = The DOF is thin, then the quality of the out of focus parts of the picture kicks in.

The last sample is from DPR which is a bad place. Don't repeat such things here...

From the above we can learn that "bokeh" isn't limited to the foreground or the background only. In general we think of the background as it is much more common with backgrounds than foregrounds. When choosing a lens I'm never interested in how it renders the OOF parts of the foreground. (Those that are have an excellent lens in the FA50/1.4.)

What about the bokehmania that hit the forums for a couple of years? Nothing special really. I think many want to use the word, many are seeking ways of expressing themselfs when taking pictures and a lot of experiments are going on now when we don't have to deal with chemical developing (and good photo editors are available). People communicate and pictures can easily be posted.

To me the real thing with the OOF areas are that I want them to just be there. They shall not make the beholder confused. They shall not make the beholder look at other things in the picture. They shall be soft and creamy and literally stick to the background helping the real content of the picture to reach the beholder.

When OOF highlights get green, or get bright rings, it can be distracting. When OOF stuff gets green (due to axial CA) it seldom enhances the picture. When OOF highlights are rendered with odd shapes due to the cat eye's effect it make the beholder to look at it and lose focus. Things going in and out to and from the focus plane should be rendered smoothly, in a way that doesn't keep the brain occupied trying to figure out what it is looking at.

In short; I want the OOF areas not to stand out.

This is valid for 99% or so of all pictures. The last 1% are pictures where the photogrpher seeks odd effects for the sake of it, as when the balls in the Christmas tree makes for funny blobs and such.

Part 2:

Lately the Sony/Minolta 135mm STF lens has been mentioned a lot. I want one. Just as carpents says; it's a reason to buy a Sony camera... that one, and the Zeiss/Minolta version of the 85/1.4.
If you have a 135mm STF collecting dust please let me know! If it is boring it is the right lens for me.

And another thing; I had some mail contact with a guy that has an STF lens fitting to a Nikon. Oh well... All sorts of things can be done. From the Nikon mount it isn't far to a Pentax mount. From either of them one can easily imagine an adapter and suddenly th lens fits a Canon, or an Olympus, as well...

Part 3:

There are a lot of new nicks here since I used to visit! Cool. I like this forum as it is reasonably moderated and free from ads. I enjoyed this thread. All the best to you all from me.

--
Jonas

(did you really read all this?)


and a random one:

E-510, Oly kit lens, my last picture of 2007, 1/45 of a second, Yeah! Fireworks... A few hours later it was mty head that exploded.
01-09-2008, 08:45 PM   #34
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hey jonas

interesting post . I am not really sure that bokeh = "quality of the out of focus parts of the picture", as in japanese bokeh , literally means "blur" / "fuzziness" .

Wikipedia says : Bokeh (from the Japanese boke ぼけ, "blur") is a photographic term referring to out-of-focus areas in an image produced by a camera lens. ...

From The Photographic Glossary: your Photo help page : Bokeh describes the rendition of out-of-focus points of light. Differing amounts of spherical aberration alter how lenses render out-of-focus ...

From the world of digital photography. Digital Camera Glossary : In Japanese , this term literally means “blur,” and in photography, this is an out-of-focus quality that comes as a result of certain photographic compositions. Normally, this is seen in photographs that utilize a large aperture.

Leica says that : When you use a lens at a wide aperture (ƒ1 - ƒ5.6), 'Bokeh' refers to the out of focus portions of the image - in particular its visually pleasing nature or lack thereof. Now leica must be dumb because a lens at 5x magnification even with f32 will only focus less about a mm or less ( not sure but it will be very small ) . But it says that bokeh refers to the out of focus portions of the image , then it says its visually pleasing nature . So to my mind that means that bokeh refers to the out of focus portions , but we are interested more in the quality . Thats what I understand ....

Even if bokeh doesn't refer to just the blur but it refers to the quality of the blur ( OOF parts ) , this doesnt mean that bokeh equals "quality of the OOF parts" , so you can't replace it whenever you see the term bokeh . Open a dictionary and you'll see what I mean . What you are describing is the definition of the word .

Anyway I maybe wrong , I am not really sure ... but the problem is that there is no official defintion ... thats why it is a little foggy . What I do think is that "Bokeh describes the rendition of out-of-focus points of light." see the word DESCRIBES not = / equal . It's different to say "bokeh is..." than "bokeh describes..." or "bokeh refers to" . Sorry but my english is not the best... so I may be totally wrong . But if this is the case , you can't replace the word bokeh with "quality of the out of focus parts of the picture" . I think... lol

Anyway ... I don't really care but it would be nice to know how use the word correctly .

I am surprised that you haven't tested the 50mm DFA or have you ... this lens gives the best bokeh of all the lenses I have seen , including all the star and limited lenses . The 70mm gives nice bokeh as well . But that's my opinion ....

what about the voigtlander 125 apo macro ?

have fun

btw I am quite sure you have read it but for those you haven't this is a nice link for bokeh : bokeh


Last edited by mer; 01-09-2008 at 09:04 PM.
01-09-2008, 08:57 PM   #35
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QuoteOriginally posted by Jonas B Quote
Hi everybody!

(did you really read all this?)[/COLOR]

and a random one:
. . .
E-510, Oly kit lens, my last picture of 2007, 1/45 of a second, Yeah! Fireworks... A few hours later it was mty head that exploded.
Yes, and hope your head has recovered in the past 9 days!
01-09-2008, 09:00 PM   #36
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Bokeh

Im surprised how good the bokeh is on the FA 80-320mm Pentax lens.This was a bright sunny day at the beach.

Last edited by trumpyman; 01-22-2008 at 01:59 PM.
01-09-2008, 09:23 PM   #37
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bokeh Sigma 17-70mm

I rekon the sigma has good bokeh to.Attachment 7447

Last edited by trumpyman; 01-22-2008 at 01:59 PM.
01-09-2008, 11:01 PM   #38
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QuoteOriginally posted by trumpyman Quote
Im surprised how good the bokeh is on the FA 80-320mm Pentax lens.This was a bright sunny day at the beach.
Well...the beach looks nice, but the seaweed - not so hot.

QuoteOriginally posted by trumpyman Quote
I rekon the sigma has good bokeh to.Attachment 7447
Now look at THAT! Do you have any pictures that show the bright highlights like in Jonas' thread? This looks promising, I think.

01-10-2008, 07:02 AM   #39
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I have tried a lot of lenses and I must say that it is almost impossible to find a reasonably sharp lens that doesn't exhibit bright rings around background highlights to some extent. The plunger cams, monocle experimental lenses, Portragon 100/4 and Sima 100/2 don't really qualify as a sharp lenses, even though their out of focus highlights do look very... soft.

Among the "sharp" lenses of normal focal length, the smoothest I have found is the old Takumar 58/2.4 lens. It's a 5 element/3 group lens of Heliar formula. It is rather soft at 2.4 but sharpens up nicely at f/4 while delivering very smooth bokeh. Here are some pictures taken with this lens at f/4 (no sharpening applied):







100% crop from above photo:


Cheers!

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01-10-2008, 08:07 AM   #40
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I did some testing in my minolta days...tried to create a standaradized setup that anyone could build at home to test bokeh of lenses.

Boke Testing



For further discussion...The reason lenses do well in greens is because of the axial chromatic abberations in the background specular highlights:

Minolta 200mm f2.8 APO G HS (regarded as having VERY good bokeh)


Think of it this way, over a green background, a 'green ring' surrounding the background specular results in the transition from the otherwise "normal" bokeh being smoothed out, EFFECTIVELY becoming very close to gaussian in nature. Result?



From the same lens.

Interesting, no?
01-10-2008, 08:21 AM   #41
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dbradley: interesting indeed. So does that mean we have to categorize good bokeh lenses into a "good at plant life bokeh" vs. "good at non plant life bokeh"? :-)
The latter certainly seems to be what carpents was after...
01-10-2008, 08:32 AM   #42
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QuoteOriginally posted by kenyee Quote
dbradley: interesting indeed. So does that mean we have to categorize good bokeh lenses into a "good at plant life bokeh" vs. "good at non plant life bokeh"? :-)
The latter certainly seems to be what carpents was after...
Technically, yes. Not all lenses have the show the 'green ring' and even those that do may only do it at certain (usually larger) apertures. Know thy lens, know thy subject...
01-10-2008, 08:36 AM   #43
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QuoteOriginally posted by d.bradley Quote
I did some testing in my minolta days...tried to create a standaradized setup that anyone could build at home to test bokeh of lenses.
Thank you!
Very good idea for a set up!
01-10-2008, 08:55 AM   #44
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QuoteOriginally posted by blende8 Quote
Thank you!
Very good idea for a set up!
Thanks, I had help from the dyxum folks on that one. One tip, if you're doing this at home: don't crinkle the foil quite so much. It will space out the specular highlights making them a little better defined.
01-10-2008, 09:14 AM   #45
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QuoteOriginally posted by d.bradley Quote
Think of it this way, over a green background, a 'green ring' surrounding the background specular results in the transition from the otherwise "normal" bokeh being smoothed out, EFFECTIVELY becoming very close to gaussian in nature. Result?

...

From the same lens.

Interesting, no?
Yes, interesting indeed. And we in the Minolta/Pentax camp should know a lot about this effect, because this type of CA is very common along both lens lines. Your advice on knowing the subject is a good one.

I have an excellent example backing this up, even more dramatic than yours - because both subjects are nominally green. The two shots below (clickable for larger size) are both from the same Nikon 50/1.4 lens, same day, same aperture.


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