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01-09-2008, 09:06 AM   #16
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FA 85 mm 1.4? too obvious of a guess? hhmmmmm...surprising results huh, how about the current kit lens?


Here's one with the SMC FA 50mm 1.4 stopped down to f/2




would this even count? I define bokeh as being something specific to backgrounds......I'm not sure if this image has a 'background' so to speak, it just merely melts into out-of-focusness

01-09-2008, 09:13 AM   #17
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For those of you who might want to browse some (Minolta/Sony) Bokeh shots, Dyxum has a contest on at the moment here that shows off a lot of different interpretations of bokeh..
01-09-2008, 09:24 AM   #18
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QuoteOriginally posted by d.bradley Quote
For those of you who might want to browse some (Minolta/Sony) Bokeh shots, Dyxum has a contest on at the moment here that shows off a lot of different interpretations of bokeh..
cool shots through that link. But that reinforces my question. Is bokeh defined as simply the out of focus part of an image or the out of focus background that emphasizes what is in focus? For example. My image fades out and compared to roentarre's example where we have a nice focused subject with the bokeh in the background.

How do you (everyone) define bokeh?
01-09-2008, 09:34 AM   #19
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QuoteOriginally posted by jshurak Quote
How do you (everyone) define bokeh?
It is simply the out-of-focus area of a photo. Yes, your guitar shot is showing the bokeh of the lens.

(PS - it really should be 'boke' without the 'h' on the end. It is silly that we - me inlcuded - deliberately misspell it.)

01-09-2008, 10:03 AM   #20
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No one will guess it? hmmm maybe a zoom? how about one of my faves an smc a-35-70mm f4???
01-09-2008, 10:19 AM   #21
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probably the old takumar 55 if my guess of 50mm was close ;-)
01-09-2008, 10:20 AM   #22
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Hey, what happened to Nesster's reply?

(Removed)

Last edited by carpents; 01-09-2008 at 10:43 AM.
01-09-2008, 10:20 AM   #23
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I will hazard a guess as well, how about 55/1.8?

01-09-2008, 10:22 AM   #24
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I wish I were home and could take a look at the pics I took with a 55/2 SMC Takumar. I formed a good opinion of it while I had it.

How about the front bokeh - it's not as good as the back bokeh, in this example. So based on this example, I'd guess the lens design over corrects near field and slightly undercorrects far?
01-09-2008, 10:25 AM   #25
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QuoteQuote:
Hey, what happened to Nesster's reply?
LOL - I deleted it when I realised it wasn't what I actually wanted to say... because this thread's getting me to look at all my pics to try to figure this thing out.

Some of the consistently good bokeh I found in my pics comes from a Richoh Diacord TLR.
01-09-2008, 10:28 AM   #26
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Drumroll please...the answer is...

The Pentax-A 50/1.2 + Pentax-F 1.7x AF Teleconverter.

That's right - the A50/1.2 on its own doesn't produce this sort of Gaussian blur for out-of-focus highlights, but when you slap on the Pentax-F 1.7x AF Teleconverter it becomes an auto-focus 85mm f/2 lens that does. The teleconverter degrades other parts of the image slightly (sharpness, for one) but in regards to the specific attribute requested in Jonas' thread it shines!

The only problem with this combination is that it doesn't calculate the widest aperture correctly. Apparently there is a bug in the Pentax calculation for the A50/1.2+1.7x AF TC combination at widest aperture. (This happens on all my Pentax cameras - if others want to confirm this feel free.)
01-09-2008, 10:32 AM   #27
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QuoteOriginally posted by Nesster Quote
I wish I were home and could take a look at the pics I took with a 55/2 SMC Takumar. I formed a good opinion of it while I had it.

How about the front bokeh - it's not as good as the back bokeh, in this example. So based on this example, I'd guess the lens design over corrects near field and slightly undercorrects far?
The SMC Takumar 55/2 is indeed a good lens. I found mine to be equal to the Pentax 50/1.7 which gets much more press.

But if you look at the image below (clickable) you see that it fails Jonas' request for Gaussian behavior on out-of-focus highlights:


QuoteOriginally posted by Nesster Quote
LOL - I deleted it when I realised it wasn't what I actually wanted to say... because this thread's getting me to look at all my pics to try to figure this thing out.
LOL, I thought there was a conspiracy against you!
01-09-2008, 10:40 AM   #28
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QuoteOriginally posted by carpents Quote
Many Pentax lenses perform spectacularly on green or muted backgrounds (like the 77 Limited).
almost anything can do "greens" nicely - that is from cheap <Sigma 24-135/2.8-4.5> @ 70mm/4.5
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01-09-2008, 10:41 AM   #29
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QuoteOriginally posted by carpents Quote
The Pentax-A 50/1.2 + Pentax-F 1.7x AF Teleconverter
Hey, that's cheating...you can't use two lenses to do ultimate bokeh! :-)

The STF lenses on that dyxseum link are cool...wish we had them :-P

Last edited by kenyee; 01-09-2008 at 12:07 PM.
01-09-2008, 10:42 AM   #30
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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...
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