RE: 77 specular bokeh talk (again!)

2002-01-05 Thread Ed Mathews

Hi Kristian,
 Yes, I saw it with the 43 also, and your photo shows it nicely.
And it's a quality I've seen in photos taken with Leica lenses too.
It's well discussed that great bokeh has been associated with a degree
of spherical aberration, and in fact the 105 F2 DC Nikkor portrait lens
actually allows the user to "dial in" some spherical aberration.  Since
what we're looking at happens differently off axis, and appears to
revolve around the center axis of the lens, I wonder if this is indeed
just a picture of spherical aberration?  This is probably why the lens
exhibits such nice background blur at larger apertures with smooth
transitions when there are no real highlights but just more even tones.
Is it literally distorting the background and blurring it into the next
tone like an artist who would be smearing wet paint?  We need a lens
guru for this one.  

Thanks,
Ed
http://lightandsilver.com 

> -Original Message-
> From: [EMAIL PROTECTED] 
> [mailto:[EMAIL PROTECTED]] On Behalf Of Kristian Walsh
> Sent: Saturday, January 05, 2002 6:13 PM
> To: [EMAIL PROTECTED]
> Subject: Re: 77 specular bokeh talk (again!)
> 
> 
> Hi Ed,
> 
> I agree, and I've seen this with pictures taken with the 43 too. The 
> only example I have isn't as clear-cut as yours, but if you 
> compare the 
> shape of the spots in the top right to those at the top of 
> the frame  in:
> 
> http://homepage.mac.com/walshk/moira.jpeg
> 
> ...you might see it.
> 
> The distortion is very slight, and I only notice the squashing of the 
> highlights with the lens wide open. Once stopped down, it's very 
> difficult to see a difference. Nothing I'm losing sleep over, and far 
> outweighed by the wonderful pictures this lens produces...
> 
> --
> Kristian
> 
> 
> On Saturday, January 5, 2002, at 10:26  pm, Ed Mathews wrote:
> 
> > Just when you thought it was safe to go back in the 
> water.  A week 
> > or so ago there was some limited  discussion about the 
> Nikon 105, 
> > it's bokeh, and the 77 bokeh.  I mentioned that the 77 yields nice 
> > bokeh, with some football (American football) shaped highlights.  
> > Nobody commented about that, and probably nobody understood what I 
> > meant.  So I thought I'd take a picture of my Christmas tree lights 
> > out of focus to show you.
> >
> > This is background bokeh, with the brightest lights about 7 
> feet away, 
> > and the lens focused to about 3 feet.  In this shot, the lens is at 
> > F2.8.  In other shots I took at smaller apertures, the 
> highlights of 
> > course get smaller, and the football shapes start to get more round.
> >
> > It appears to me that the shape becomes more oblong closer to the 
> > edge, and that they kind of look like they circle around the center 
> > axis. Tell me what you think.
> >
> > http://lightandsilver.com/Temp/77.htm
> >
> > Thanks,
> > Ed
> > http://lightandsilver.com
> > -
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Re: 77 specular bokeh talk (again!)

2002-01-05 Thread Dan Scott

Yes.

Dan Scott
[EMAIL PROTECTED]

> Any other 77 owners noticed the highlights to be
>like Ed's sample here?
>
>
>Bruce Dayton
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Re: 77 specular bokeh talk (again!)

2002-01-05 Thread David A. Mann

Ed Mathews wrote:

> I mentioned that the 77 yields nice
> bokeh, with some football (American football) shaped highlights.  Nobody
> commented about that, and probably nobody understood what I meant.  So I
> thought I'd take a picture of my Christmas tree lights out of focus to
> show you.

 I think all lenses do it - at least all the ones I've looked at (its less pronounced 
with longer lenses).

 My theory is that its caused by an internal vignetting.  Look into the lens and 
swing it around, you won't see a perfect circle through the elements from all 
angles :)  It follows that if I'm right, the effect would diminish when using lenses 
with a larger image circle.

 The effect goes away when stopped down, as you've noticed.

Cheers,


- Dave

David A. Mann, B.E. (Elec)

"Why is it that if an adult behaves like a child they lock him up,
 while children are allowed to run free on the streets?" -- Garfield
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RE: 77 specular bokeh talk (again!)

2002-01-06 Thread Ed Mathews

OK Yoshihiko, I'll accept this explanation from you and Dan (mostly
because I don't know any better myself and trust others on this).  But I
do wonder why I have only noticed it with the 43 and the 77.  At some
point, I would also like to see some sort of illustration showing what
spherical aberration looks like, if possible.  I've become intrigued by
it and way too interested in it for my own good.

I'm still considering buying an MZ-S, mainly so I can keep this 77
because I like it so much.  As I sell more stuff and actually get the
money, that decision might become even more difficult.

Thanks,
Ed
http://lightandsilver.com 

> -Original Message-
> From: [EMAIL PROTECTED] 
> [mailto:[EMAIL PROTECTED]] On Behalf Of Yoshihiko Takinami
> Sent: Sunday, January 06, 2002 5:07 AM
> To: [EMAIL PROTECTED]
> Subject: Re: 77 specular bokeh talk (again!)
> 
> 
> Hi Ed and everyone,

> It's not bokeh but just vignetting as Dan wrote.
> 
> BTW, I was really impressed at the very smooth outlines of 
> the football shapes of out-of-focus background spotlights 
> while you stopped down about one and a half stops.
> 
> Hope this helps.
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RE: 77 specular bokeh talk (again!)

2002-01-06 Thread Rob Studdert

On 6 Jan 2002 at 9:42, Ed Mathews wrote:

> OK Yoshihiko, I'll accept this explanation from you and Dan (mostly
> because I don't know any better myself and trust others on this).  But I
> do wonder why I have only noticed it with the 43 and the 77.

Ed,

See http://pug.komkon.org/00marc/tracy.htm same thing but with my 50 f/1.2, a 
little bit more edgy though.

Cheers,
Rob Studdert
HURSTVILLE AUSTRALIA
Tel +61-2-9554-4110
UTC(GMT)  +10 Hours
[EMAIL PROTECTED]
http://members.ozemail.com.au/~distudio/publications.html
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Re: 77 specular bokeh talk (again!)

2002-01-06 Thread Yoshihiko Takinami

Hi Ed,

On 6 Jan 2002 at 06:42:50 -0800 , Ed Mathews wrote:

> OK Yoshihiko, I'll accept this explanation from you and Dan (mostly
> because I don't know any better myself and trust others on this).  But I
> do wonder why I have only noticed it with the 43 and the 77.

I suppose it would be because they have much vignetting than
their counterparts for they were designed to be compact as
possible.   Think of their sizes !!  :^)

> At some point, I would also like to see some sort of illustration
> showing what spherical aberration looks like, if possible.

Spherical aberration brings some soft, or veiled, images like
Pentax soft lenses.   You can also see some sort of soft effect
by spherical aberration with K50/1.2, or A50/1.2, wide open in
the strong daylight.

> I'm still considering buying an MZ-S, mainly so I can keep this 77
> because I like it so much.  As I sell more stuff and actually get the
> money, that decision might become even more difficult.

I also do think the 77 Limited is really excellent and I love
mine.  :^)

Regards,
--
Yoshihiko Takinami
Osaka, Japan
[EMAIL PROTECTED]
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Re: 77 specular bokeh talk (again!)

2002-01-06 Thread Aaron Reynolds

I've seen these football shaped highlights with my SMC-M 50mm f1.4.

-Aaron
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RE: 77 specular bokeh talk (again!)

2002-01-06 Thread Ed Mathews

Yup.  And pretty edgy for sure.  Seems you have a lot off bad bokeh
luck. :)

Thanks,
Ed
http://lightandsilver.com 

> -Original Message-
> From: [EMAIL PROTECTED] 
> [mailto:[EMAIL PROTECTED]] On Behalf Of Rob Studdert
> Sent: Sunday, January 06, 2002 11:08 AM
> To: [EMAIL PROTECTED]
> Subject: RE: 77 specular bokeh talk (again!)
 
> Ed,
> 
> See http://pug.komkon.org/00marc/tracy.htm same thing but 
> with my 50 f/1.2, a 
> little bit more edgy though.

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RE: 77 specular bokeh talk (again!)

2002-01-07 Thread Kent Gittings

That's called spherical aberration or coma I think. Unless the aperture
diaphragm is not circular at whatever F-stop you chose.
Kent Gittings

-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of Ed Mathews
Sent: Saturday, January 05, 2002 5:26 PM
To: [EMAIL PROTECTED]
Subject: 77 specular bokeh talk (again!)


Just when you thought it was safe to go back in the water.  A week
or so ago there was some limited  discussion about the Nikon 105,
it's bokeh, and the 77 bokeh.  I mentioned that the 77 yields nice
bokeh, with some football (American football) shaped highlights.  Nobody
commented about that, and probably nobody understood what I meant.  So I
thought I'd take a picture of my Christmas tree lights out of focus to
show you.

This is background bokeh, with the brightest lights about 7 feet away,
and the lens focused to about 3 feet.  In this shot, the lens is at
F2.8.  In other shots I took at smaller apertures, the highlights of
course get smaller, and the football shapes start to get more round.

It appears to me that the shape becomes more oblong closer to the edge,
and that they kind of look like they circle around the center axis.
Tell me what you think.

http://lightandsilver.com/Temp/77.htm

Thanks,
Ed
http://lightandsilver.com
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RE: 77 specular bokeh talk (again!)

2002-01-07 Thread Kent Gittings

The faster the optical system (or F-stop) the more pronounced the coma can
be.
Kent Gittings

-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of Bruce Dayton
Sent: Saturday, January 05, 2002 6:40 PM
To: Ed Mathews
Subject: Re: 77 specular bokeh talk (again!)


Ed,

It's certainly very visible.  This is an area where the FA*85 beats
the 77 in my opinion.  It produces nice, round highlights.  I have
thought long and hard about getting the 77 and seeing this makes me
want to just keep and use my FA*85 (already paid for).  I would be
curious to know if this is consistent from sample to sample or is
there some variance.  Any other 77 owners noticed the highlights to be
like Ed's sample here?


Bruce Dayton



Saturday, January 05, 2002, 2:26:12 PM, you wrote:

EM> Just when you thought it was safe to go back in the water.  A week
EM> or so ago there was some limited  discussion about the Nikon 105,
EM> it's bokeh, and the 77 bokeh.  I mentioned that the 77 yields nice
EM> bokeh, with some football (American football) shaped highlights.  Nobody
EM> commented about that, and probably nobody understood what I meant.  So I
EM> thought I'd take a picture of my Christmas tree lights out of focus to
EM> show you.

EM> This is background bokeh, with the brightest lights about 7 feet away,
EM> and the lens focused to about 3 feet.  In this shot, the lens is at
EM> F2.8.  In other shots I took at smaller apertures, the highlights of
EM> course get smaller, and the football shapes start to get more round.

EM> It appears to me that the shape becomes more oblong closer to the edge,
EM> and that they kind of look like they circle around the center axis.
EM> Tell me what you think.

EM> http://lightandsilver.com/Temp/77.htm

EM> Thanks,
EM> Ed
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