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View Full Version : Bokeh again: aperture blades round or edgy?



ramin
20-Sep-2005, 16:26
One thing that is responsible for a pleasing bokeh is a round iris when the lens is stopped down. Nevertheless I am aware that some lens designs do posses a good bokeh despite having an edgy iris like the Nikkor 35 1.4 but again there have been manufacturers (more in the past though) who have added more diaphragm blades to create this round look so it looks like this does play a big role in bokeh quality. May be this is the reason we like our lenses wide open?

I have checked my optics for this and want to share it with you:

My Apo sironar 210-S, G-Claron 150 (typical symmetrical or near symmetrical designs) SA 72XL and my Konica Hexars 35mm fixed lens all show a round iris, the Hexar has actually a very beautiful bokeh something very special among all of my optics. My 110 xl and Apo tele xenar 400 show an edgy shape.

All of my Bronica SQ lenses (80, 50 and 200) show an edgy iris though I like the 80 wide open. Nikkor 35: 35 1.4, 105 1.8, 55 2.8 micro and 28 PC are all edgy. The 35 1.4 is a very contrasty optic and is famous for having a "complex" bokeh. Again I like this lens wide open and it does have a good bokeh but not at close ups.

To check your optics point your lens set at infinity at a ball of crushed aluminum foil lit by a strong light like a table lamp. Then stop your lens down and look for the circle of confusion. For rangefinders open the back and place a small ground glass on the film plane.

Dan Fromm
20-Sep-2005, 17:54
Huh?

Its time for a poll. What apertures do you typically use?

35 mm, macro up to 1:1? f/16 - f/27 marked. Effective smaller.

35 mm out and about? f/5.6 to f/16, depending.

2x3 macro, up to 2:1? f/20

2x3 out and about? f/11 - f/22, depending.

Dan Fromm
20-Sep-2005, 17:55
Huh?

Its time for another poll.

Whose pictures often suffer from bright highlights in the out-of-focus areas that are rendered as images of the lens' diaphragm?

Not mine.

Ted Harris
20-Sep-2005, 20:25
The problem as it relates to modern large format lenses is that none of them have diphragms. The diphragms are in the shutter and today the only shutters being manufactured come from Copal. Within the past few years both Compur and Prontor stopped making LF shutters although there could easily still be some in dealer stock. I haven't numbers of blades but the Compurs and Prontor Pro's both have more blades than the Copals. So, regardless of your lens it is highly likely to be mounted in a Copal shutter.

John_4185
20-Sep-2005, 21:16
http://elearning.winona.edu/jjs/tmp1.gif

愉快模糊

Oren Grad
20-Sep-2005, 21:28
That's a special version of the Copal Press #0, known as the Copal Press Smiley #0, sold only in Asian markets...

Frank Petronio
21-Sep-2005, 00:13
FWIW, after dabbling with shutter mounted and non-mounted lenses, the rounded openings of the non-shutter mounted lenses make images that are vastly more pleasing. Of course this is for wide aperture portraits with backlight, not your typical West Coast landscape stopped down to f/22.

It actually is part of the reason I stopped trying to do close portraits with shutter mounted large format lenses. And why I am about the throw this darn Nikkor 50/1.4 AF lens against the wall (harsh hexagonal bokeh).

Ole Tjugen
21-Sep-2005, 02:27
If you want lots and lots of aperture blades in a shutter, you'll have to get a classic "oldie" in a Compound #5 shutter. I think it's 23 aperture blades. Look for a Heliar 300mm f:4.5 in shutter - the "King of Bokeh"!

Oren Grad
21-Sep-2005, 07:05
Frank, I tossed my 50/1.4 AF Nikkor out the window a long time ago. Stopped down or flat out, between the bokeh and the tonal gradation, it's one of the harshest lenses I've ever used.

Michael Jones
21-Sep-2005, 08:04
While this is all terribly fascinating; I come away with the thought: What would Edward Weston think about all this? Oh my...

jj comes closest to my response.

Mike

paulr
21-Sep-2005, 08:59
"What would Edward Weston think about all this?"

Early in his career when he was a pictorialist, and supported himself making portraits, he probably had a few conversations just like this. Later on when he joined the f64 militia, none of it would have mattered because he made images with everything pretty much in focus.

I never thought about this stuff for a minute until recently .. the project i was working on for years required everything to be sharp. The first time someone asked me about the bokeh of my LF lenses, I had no idea. I'd truly never seen it. For the first time now I have some selective focus going on in my pictures, so I'm having to learn a bit about all this.

Ken Lee
21-Sep-2005, 11:02
A friend translated 愉快模糊 for me: It means "happy fuzz", a nice little joke about "good bokeh" or "pleasant bokeh". In this case, the bokeh is *very* happy.

Is that right, jj ?

Frank Petronio
21-Sep-2005, 13:17
I always thought that talk about bokeh was horses#*t that amateurs yakked about because they were lousy photographers. Then I started to play with selective focus, and then started making more and more photos with out of focus areas.

It's not large format, but when I used a Leica 35/1.4 it was possible to have a wide angle and to control the focus - it is a pretty sweet way to work, and used subtlety it gives your photos more of a 3-D depth.

John_4185
21-Sep-2005, 13:27
Ken Lee A friend translated 愉快模糊 for me: It means "happy fuzz", a nice little joke about "good bokeh" or "pleasant bokeh". In this case, the bokeh is *very* happy.

I'm surprised you found a traditional Chinese translator. He is correct! If I could find a Japanese person, I'd have done it in the proper language, but all my help is Chinese.

Oren Grad
21-Sep-2005, 15:40
It's not large format, but when I used a Leica 35/1.4 it was possible to have a wide angle and to control the focus - it is a pretty sweet way to work, and used subtlety it gives your photos more of a 3-D depth.

Yes, pan focus often will tend to "flatten" a scene. One of the things that sensitized me to OOF effects was trying different 35s for M-Leica and realizing how differently they behaved in this respect.