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09-28-2008, 02:05 PM   #31
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Too bad this is not a K-mount:



I have been told its register distance is about 1/3 of the K-mount distance, so it would work like a lens on an extension tube. The 8 aperture blades are oddly rounded in the opposite direction of what you'd think.

09-28-2008, 02:15 PM   #32
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QuoteOriginally posted by thePiRaTE!! Quote
?I'm simply suggesting people are misinformed that it actually matters beyond shape, which is subjective.
I don't think anyone is claiming that it number of blades affects anything *but* the shape of out-of-focus highlights. However, while you are of course correct in stating the hexagon versus circle is a subject preference, it's one that *most* people agree on (you may happen to be an exception). Similarly, there is no objective sense in which a sharper lens is better than a softer one, but again, most people *do* agree on this, so it's not much of a stretch to talk about it as if it were objectively true. I'd say it's only *slightly* less appropriate with number of aperture blades.
09-28-2008, 05:53 PM   #33
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QuoteOriginally posted by thePiRaTE!! Quote
? I mentioned them specifically...
going that way we can exclude everything else and leave only a uniformly painted wall in the background and then all lenses at any aperture will be equal, 17mm @ f32 will have the same blur as 85 @ 1.4...way to go... you can't exclude highlights from consideration as they happens to be in the background quite often in the real life... you happen to like pronounced hexagons - but most people like it as close to the perfect circle as possible...
09-28-2008, 05:56 PM   #34
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QuoteOriginally posted by thePiRaTE!! Quote

Funny thing is, I can't argue with that. Perhaps green is better than blue for you. I'm simply suggesting people are misinformed that it actually matters beyond shape, which is subjective.
Cone cell - Wikipedia, the free encyclopedia

QuoteQuote:
At moderate to bright light levels where the cones functions, the eye is more sensitive to yellowish-green light than other colors because this stimulates the two most common of the three kinds of cones almost equally. At lower light levels, where only the rod cells function, the sensitivity is greatest at a blueish-green wavelength.


09-29-2008, 08:04 AM   #35
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QuoteOriginally posted by Just1MoreDave Quote
Too bad this is not a K-mount:



I have been told its register distance is about 1/3 of the K-mount distance, so it would work like a lens on an extension tube. The 8 aperture blades are oddly rounded in the opposite direction of what you'd think.
I personally long for the day a lens of such aperture would be available, whether by mod or design, for the K-mount. I didn't know there were any others besides the Canon & Leica, I'm left to wonder if there are more?

QuoteOriginally posted by Marc Sabatella Quote
I don't think anyone is claiming that it number of blades affects anything *but* the shape of out-of-focus highlights. However, while you are of course correct in stating the hexagon versus circle is a subject preference, it's one that *most* people agree on (you may happen to be an exception). Similarly, there is no objective sense in which a sharper lens is better than a softer one, but again, most people *do* agree on this, so it's not much of a stretch to talk about it as if it were objectively true. I'd say it's only *slightly* less appropriate with number of aperture blades.
I agree with everything said here. I only mentioned initially a general observation made between the correlation of # of blades to oof. It was just a statement made as infomation on the topic, not in direct disagreement with anyone. Its an easy line to draw, # of blades to bokeh quality, by use of the term 'better' in place of 'rounder', as it did subsequently here.

Through these very forums for months I had interepretted that more blades was better. I found a Schneider 80/5.6 which has 15 blades. At 5.6 though, its a little stunted in the oof dept. It was that, and finally cutting out the hexagon aperture into my VL 125 when I discovered what maybe many know, but perhaps maybe many don't and I like to share.

FWIW -

VL125 @ 2.5 au natural


VL125 @ with hexagon inserted. (Note, amount if blur is reduced as my hexagon image circle had to become quite small (around the size of f8) in order to become readily apparent in the highlights. Larger hexs did not, or barely appeared).


QuoteOriginally posted by deejjjaaaa Quote
In your post on using painted walls, you create an analogy ignoring my stated experience in an invented scenario. Here you're arguing against an analogy of the original point and not the point. If it matters to you so much to be right regardless of fact - just believe what you like, you're going to anyways.
09-29-2008, 08:52 AM   #36
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QuoteOriginally posted by thePiRaTE!! Quote

In your post on using painted walls, you create an analogy ignoring my stated experience in an invented scenario.
you experience is that you like highlights in the shape of hexagons - so be it... however you can't arbitrary exclude certain elements from consideration how oof areas will look like to suit your agenda...
09-29-2008, 08:56 AM   #37
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QuoteOriginally posted by thePiRaTE!! Quote
FWIW -

VL125 @ 2.5 au natural


VL125 @ with hexagon inserted. (Note, amount if blur is reduced as my hexagon image circle had to become quite small (around the size of f8) in order to become readily apparent in the highlights. Larger hexs did not, or barely appeared).
it is not а good comparison, either you need to stop down to f8 (for "VL125 @ 2.5 au natural") w/o hexagon inserted and with hexagon inserted _or_ your inserted hexagon is exactly not representing how 6 blades aperture will behave in the same lens wide open @ f2.5... the correct comparison should be done on lenses w/ quite similar optical schemes (like A1.4 vs A1.7) where you have for example 8 vs 6 blades... and certainly - you need to compare not only at wide open apertures, but stopped down - there the ugliness of hexagons will shine.
09-29-2008, 11:03 AM   #38
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Agenda? nah, just experience. Hexagons, circles, stars, hearts... use what you like and if you like circles, you'll probably prefer 9 blades to 6 for your highlights. Its subjective, thats the point. I rather wish aperture interchangeability was more common practice in a traditional lens as it is with lens babies for example -

Lensbabies Creative Aperture Kit - PhotographyBLOG
(scroll down for samples)

09-29-2008, 11:38 AM   #39
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QuoteOriginally posted by thePiRaTE!! Quote
I rather wish aperture interchangeability
that to some extent can be done through filters.
09-29-2008, 11:44 AM   #40
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QuoteOriginally posted by deejjjaaaa Quote
... and certainly - you need to compare not only at wide open apertures, but stopped down - there the ugliness of hexagons will shine.
The aperture shape doesn't matter wide open. There may be a few lenses where the blades still protrude a bit all the time, but on all of the ones I have here, wide-open means wide open. My Pentax-F 50mm f1.7 with 6 blades has beautiful/ugly circular OOF highlights at f1.7, and ugly/beautiful hexagonal OOF highlights at other apertures.
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