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01-19-2010, 07:26 AM   #1
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definitely not the flat earth society

Is there any interest in a club dedicated to lenses which have a round aperture as opposed to hexagonal or octagonal?

I'm talking about all those lenses with 12-18 blade apertures, and /or sculpted blades that keep the aperture round

these lenses have a unique bokeh all thier own

01-19-2010, 07:54 AM   #2
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I don't have such a beast, but can you post an example from one so I can see the creamy bokeh?
01-19-2010, 08:35 AM   #3
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It's mostly due to the lens design build, not the aperture shape (since this doesn't matter when it is wide open). All lenses will have a round aperture when wide open, but only those with sculpted blades/many blades will have a round aperture when stopped down at all.

Typically, designers that put much care into the aperture shape will also have good bokeh (both wide open and stopped down).
01-19-2010, 08:36 AM - 1 Like   #4
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I had such a beast, quite sharp, but not color corrected.
Meyer Orestegor 300mm



The Bokeh circles are round, but nothing more:


01-19-2010, 09:19 AM   #5
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QuoteOriginally posted by Eruditass Quote
It's mostly due to the lens design build, not the aperture shape (since this doesn't matter when it is wide open). All lenses will have a round aperture when wide open, but only those with sculpted blades/many blades will have a round aperture when stopped down at all.

Typically, designers that put much care into the aperture shape will also have good bokeh (both wide open and stopped down).
Blende8 gave a good example of what I am looking for.

The lenses in this club will be scattered throughout different makers.

I have a 200mm Takumar with 15-16 blades.

The types of things I suspect that people would post are the OFF details like Blende posted, and also the starburst you see from difraction interference around the minor discontinuities at the intersection of the blades.
01-19-2010, 10:20 AM   #6
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I noticed the Takumar 300/4 is another lens that has 18 blades in it too.
I wouldn't mind one of these actually.
01-19-2010, 10:31 AM   #7
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I think my Russian Tair 300 has 16 blades, but I haven't had a chance to try it properly yet.

The shots in the Russian Club thread look impressive though.

01-19-2010, 10:38 AM   #8
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QuoteOriginally posted by Mechan1k Quote
I noticed the Takumar 300/4 is another lens that has 18 blades in it too.
I wouldn't mind one of these actually.
I think with the takumars, it is only the presets with high number of blades.

at least with the mix of taks, super taks and SMC tak's that I have
01-19-2010, 10:47 AM   #9
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It might be as well .. I saw one recently on eBay go for couple hundred.
Reason i noticed the blades was a shot that was posted up with an internal shot of the lens. (Which i can't find now )
01-19-2010, 10:50 AM   #10
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Very impressive Wieland - I've never seen such a grand multi-blade animal...
The only other round aperture lenses I know of are the lensbabies and mirrors - but we have clubs for those already...
01-19-2010, 11:26 AM - 1 Like   #11
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QuoteOriginally posted by Mechan1k Quote
It might be as well .. I saw one recently on eBay go for couple hundred.
Reason i noticed the blades was a shot that was posted up with an internal shot of the lens. (Which i can't find now )
OK ... I'll quote myself.

Here's a shot of Groucho's Takumar 300/4 ... 18 blades of goodness

01-19-2010, 02:49 PM - 1 Like   #12
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Nice idea, and I guess we are looking at very old lenses or very new ones. I'd love to have
a new Voigtländer and Zeiss (which I think all have those rounded blades). For the time being,
here's the Tair 300/4.5.



Blade counting is easier here,
01-19-2010, 08:51 PM   #13
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My cheap Tamron 400mm f/6.3 that i just picked up from the Post office has 13 blades surprisingly.
01-20-2010, 07:27 AM   #14
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here's the lens in my kit that prompted the thread.

I think I count 18 blades.
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06-21-2010, 12:45 PM   #15
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I have the Takumar 200/3.5 200/5.6 and 135/3.5 presets and can only account for the 200/3.5 as having more than 10 blades, the others are eight (and half the size and a lot lighter).

The only other I know of that might have a plethora of blades are mostly the other presets. Maybe the older helios-44 2 or the jupiter-9 fit in here?
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