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+--- Thread: Clarification from Klaus on Aperture Blades? (/showthread.php?tid=2814)
Clarification from Klaus on Aperture Blades? - Optic_Junkie - 11-30-2011
Hi Klaus
In your review of the Pentax DA-L 35mm f2.4 under the 'Bokeh' section, you wrote: "The Pentax lens does a rather average job here which is typical for lenses with aspherical elements. Out-of-focus highlights can show an outlining effect and aperture shape gets already visible at f/3.2 - the latter aspect is an effect of the non-circular aperture blades."
Can you clarify as to whether the lens has straight aperture blades, or curved aperture blades (as found in the DA*55 and D-FA 100)? I'm assuming "non-circular aperture blades" was a typo, and you instead meant to refer to "curved aperture blades" and/or a "circular aperture". Thanks
Clarification from Klaus on Aperture Blades? - Klaus - 11-30-2011
[quote name='Optic_Junkie' timestamp='1322618169' post='13367']
Hi Klaus
In your review of the Pentax DA-L 35mm f2.4 under the 'Bokeh' section, you wrote: "The Pentax lens does a rather average job here which is typical for lenses with aspherical elements. Out-of-focus highlights can show an outlining effect and aperture shape gets already visible at f/3.2 - the latter aspect is an effect of the non-circular aperture blades."
Can you clarify as to whether the lens has straight aperture blades, or curved aperture blades (as found in the DA*55 and D-FA 100)? I'm assuming "non-circular aperture blades" was a typo, and you instead meant to refer to "curved aperture blades" and/or a "circular aperture". Thanks
[/quote]
non-circular aperture blades = straight blades
Clarification from Klaus on Aperture Blades? - Optic_Junkie - 11-30-2011
Indeed - this would seem obvious to me as well. So, the Pentax DA-L 35mm f2.4 doesn't have curved aperture blades of any kind; it has straight blades. Is that correct?
[quote name='Klaus' timestamp='1322634989' post='13373']
non-circular aperture blades = straight blades
[/quote]
Clarification from Klaus on Aperture Blades? - Brightcolours - 11-30-2011
[quote name='Optic_Junkie' timestamp='1322636922' post='13376']
Indeed - this would seem obvious to me as well. So, the Pentax DA-L 35mm f2.4 doesn't have curved aperture blades of any kind; it has straight blades. Is that correct?
[/quote]
As the sample image clearly shows, this particular lens has 6 aperture blades that not rounded at all. About as straight as the 5 aperture blades my 35mm f2 has when stopped down.
Not sure where you are going with this? <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/blink.gif' class='bbc_emoticon' alt=':blink:' /> If you want to point out that you can detect a slight curve in the blades when stopped down, don't. We call blades "curved" when they more or less produce rounded apertures, and this Pentax clearly does not do that.
Clarification from Klaus on Aperture Blades? - Optic_Junkie - 11-30-2011
Well, I personally, am not going anywhere with it.
http://forums.dpreview.com/forums/read.asp?forum=1036&message=39951648
[quote name='Brightcolours' timestamp='1322641703' post='13380']
As the sample image clearly shows, this particular lens has 6 aperture blades that not rounded at all. About as straight as the 5 aperture blades my 35mm f2 has when stopped down.
Not sure where you are going with this? <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/blink.gif' class='bbc_emoticon' alt=':blink:' /> If you want to point out that you can detect a slight curve in the blades when stopped down, don't. We call blades "curved" when they more or less produce rounded apertures, and this Pentax clearly does not do that.
[/quote]
Clarification from Klaus on Aperture Blades? - mst - 11-30-2011
[quote name='Optic_Junkie' timestamp='1322672091' post='13397']
http://forums.dpreview.com/forums/read.asp?forum=1036&message=39951648
[/quote]
Geez, what a waste of time...
-- Markus
Clarification from Klaus on Aperture Blades? - Optic_Junkie - 11-30-2011
Agreed; it looks like the admin banned some people over there after the guy starting calling Klaus a liar. DPR is full of morons.
[quote name='mst' timestamp='1322682282' post='13405']
Geez, what a waste of time...
-- Markus
[/quote]