Tominon 127mm Doesn't Match Shutter?

On 2/5/2004 8:49 PM jjs spake thus:

In article , David Nebenzahl
wrote:

Actually, I am. Look; no two people can actually agree on what constitutes
"good bokeh" or "bad bokeh". I'm not saying that there aren't differences
between out-of-focus backgrounds due to, among other factors, aperture shape;
but if you read about this subject much at all, you quickly reach the
how-many-zen-masters-taking-photographs-can-dance-on-the-head-of-a-pin stage.

All I know about zen masters would fit on the head of a pin, but the
qualities of bokeh are mysteries I'd rather call personal and cultural.
But it exists. I don't see much LF work that has bokeh. Most is stopped
down to the max, or has subjects farther than 30 feet (relative size to
the POV) so bokeh doesn't exist in such subjects.

groan Don't know if I should open this particular can of worms, but here
goes: when you say you don't see much LF work with bokeh, what you're really
saying that you don't see much LF work with out-of-focus backgrounds. (Which
isn't in dispute.) "Bokeh" is more than just the out-of-focus background
itself: it's mystical mumbo-jumbo which supposedly describes (and
discriminates) the *qualities* of that out-of-focusness: hence "good" and
"bad" bokeh. (Which I liken to good and bad juju, mon.)

By the way, some of my favorite SovCam lenses (35mm Leica mount) are spozed to
have good bokeh: the Jupiter-8 and -3.


--
It's fun to demonize the neo-cons and rejoice in their discomfiture, but
don't make the mistake of thinking US foreign policy was set by Norman
Podhoretz or William Kristol. They're the clowns capering about in front of
the donkey and the elephant. The donkey says the UN should clean up after
them, and the elephant now says the donkey may have a point. Somebody has
come out with a dustpan and broom.

- Alexander Cockburn, _CounterPunch_
(http://www.counterpunch.org), 9/17/03

David Nebenzahl wrote:

On 2/5/2004 8:49 PM jjs spake thus:

In article , David Nebenzahl


By the way, some of my favorite SovCam lenses (35mm Leica mount) are
spozed to have good bokeh: the Jupiter-8 and -3.



Probably why they are your favorites...

Most "classic" good lenses have great bokeh, lenses with harsh bokeh are the
ones no one ever raves about. Both of the lenses you mention above are
probably sonar clones which almost always have wonderful bokeh. Tssar
lenses, while sharp have a sort of clumpy bokeh and some of the sharpest
lenses made in 35mm have 2 line bokeh which can be quite distracting. There
are other lens designs whose bokeh isn't easily described but it does
exist.

An example of LF bokeh was with my 8X10, I wanted to play with some wide
open shooting with the 300mm f4.5 tessar that came with my camera and it
wasn't very pretty, I bought a voighlander heliar 300mm f4.5 and the wide
open shots with it were much more interesting. It was all about the out of
focus portions that differed. Yes it's a personal choice thing but if you
showed 10 people these 2 shots, I doubt anyone would pick the tessar ones
as being better.

--

Stacey

On 2/6/2004 4:29 PM Stacey spake thus:

David Nebenzahl wrote:

By the way, some of my favorite SovCam lenses (35mm Leica mount) are
spozed to have good bokeh: the Jupiter-8 and -3.

Probably why they are your favorites...

Most "classic" good lenses have great bokeh, lenses with harsh bokeh are the
ones no one ever raves about. Both of the lenses you mention above are
probably sonar clones which almost always have wonderful bokeh.

Yes; both the J-3 and J-8 are copies (very good ones) of the Sonnar. The J-3
is the fast one (f/1.5).

Tssar lenses, while sharp have a sort of clumpy bokeh and some of the sharpest
lenses made in 35mm have 2 line bokeh which can be quite distracting.

What, pray tell, is "2-line bokeh"?


--
It's fun to demonize the neo-cons and rejoice in their discomfiture, but
don't make the mistake of thinking US foreign policy was set by Norman
Podhoretz or William Kristol. They're the clowns capering about in front of
the donkey and the elephant. The donkey says the UN should clean up after
them, and the elephant now says the donkey may have a point. Somebody has
come out with a dustpan and broom.

- Alexander Cockburn, _CounterPunch_
(http://www.counterpunch.org), 9/17/03

David Nebenzahl wrote:

On 2/6/2004 4:29 PM Stacey spake thus:

Both of the lenses you mention above
are probably sonar clones which almost always have wonderful bokeh.

Yes; both the J-3 and J-8 are copies (very good ones) of the Sonnar. The
J-3 is the fast one (f/1.5).


I figured as much.



Tssar lenses, while sharp have a sort of clumpy bokeh and some of the
sharpest lenses made in 35mm have 2 line bokeh which can be quite
distracting.

What, pray tell, is "2-line bokeh"?



The first image on this page shows a double spire in the background (mirror
lens). That is an example of 2 line or double line bokeh. Nikor and many
other japanese lenses, especially their fast tele lenses, are known for
this "defect". Some people love the sharpness these have but the background
blur can be distracting if the wrong types of things are in the background.

http://www.trenholm.org/hmmerk/ATVB.pdf


Here are a few more articles on the subject.


http://www.kenrockwell.com/tech/bokeh.htm

http://hobbymaker.narod.ru/English/A.../bokeh_eng.htm

http://www.luminous-landscape.com/essays/bokeh.shtml

On my Kiev lenses, the 250mm telear is a VERY sharp lens but has harsh
bokeh. Care must be used to keep -lines- out of the background as they look
awful if they are rendered too out of focus. Something like a sonar doesn't
have this problem.

One thing can be said for harsh lenses, they can appear to have deeper DOF
than a smooth bokeh lens like a sonar. Depending on what you are trying to
do with an image this can either be a plus or minus. When I use the 250
telear, I'm ussually wanting more DOF than the lens should produce so this
harshness can help. I think many LF lenses are like this and it does help
more of the image appear to be within acceptable sharpness, but produce
ugly images shot wide open.


I've been playing with shooting my 8X10 wide open and it's hard to find a LF
lens that looks nice. I don't need sharpness making contact prints, I need
smooth bokeh. So far a very old heliar looks the best I've tried.

--

Stacey

hi Stacey ;-)

you make another interesting point, namely, that none of the published
guides I have seen rate LF lenses on their bokeh. Here again, adding this
category to a user review of LF lenses would be easy, and might show some
consensus about which lenses have better or worse bokeh (just as the
nikkor 105mm f/2.5 is often cited as among the top bokeh lenses in that
lineup etc.)...

Since I suspect that spherical aberration is the source of much good
bokeh, the fact that triplets and lens cells would have more uncorrected
aberrations than a four element (tessar..) and fully corrected main lens
would not be surprising. This may be one of those cases where older and
cheaper (fewer elements..) may be better? ;=)

grins bobm
--
************************************************** *********************
* Robert Monaghan POB 752182 Southern Methodist Univ. Dallas Tx 75275 *
********************Standard Disclaimers Apply*************************

Bob Monaghan wrote:



Since I suspect that spherical aberration is the source of much good
bokeh, the fact that triplets and lens cells would have more uncorrected
aberrations than a four element (tessar..) and fully corrected main lens
would not be surprising. This may be one of those cases where older and
cheaper (fewer elements..) may be better? ;=)


And with most of these lenses, when used at the small f-stops most LF
users use, these "defects" are corrected by stopping down.

I made a "soft focus" lens for my K-60 by taking a dead 80mm biometar and
removing all the glass except for the front element. I was shocked how good
it is at f16-f22 for 1 piece of glass.
--

Stacey

The element separation is the same, the 75 was a tessar macro lens, meant to
give the MP-4 a macro (micro?) capability. But with 4 lights stuck out to the
side was difficult. Without the exact specs on the lens it would be almost
futile to screw or unscrew the rear element and make any difference. This lens
was not a star, and if it is soft so be it.

Tom


In article ,
says...

Stacey wrote in message
...

Lo and behold, i checked my shutter, and athough it's a Copal
one type shutter, on the side it says 3 inches/75mm!

I suppose this would explain why the pics are noticably less
sharp in the center than the Schneider?



I doubt the cell spacing is any different between the 2 shutters, but could
make the f stop scale off.


Ok, so the lens spacing for a 75mm and for a 127mm are exactly
the same?

The f stop scale being off would explain why I thought my
Luna-pro has been way off! Way underexposed at first!

Ok, i'm gonna tighten the rear cell a bit and see if things don't
get a bit sharper. And i'll try f22.


Slick

yes, interesting lens "hack" ;-)

A previous poster asked about Andreas Feininger's project using an 8x10"
and a magnifying glass to shoot the NYC skyline out their office (Modern
photo?). The wide open glass was indistinct and blurry, but stopped down
with a cardboard stop, and the dang lens looked amazingly sharp for a $5
office magnifier ;-)

see http://medfmt.8k.com/mf/elements.html on a few elements going a long
way ;-)

my specific interest here is shortwave UV using quartz element (single
element to cut high costs, as with +10 diopter soft focus portrait lens).
Here again, a stop will deliver some surprisingly decent images in the far
UV for far less than $3-10,000 for a zeiss quartz UV lens ;-) (see
mf/uv.html)

grins bobm

PS did you hear about the hassy portrait shooter whose signature images
were shot through a lens which had been steel wool scraped to put in
zillions of fine scratches? Takes all kinds ;-)
--
************************************************** *********************
* Robert Monaghan POB 752182 Southern Methodist Univ. Dallas Tx 75275 *
********************Standard Disclaimers Apply*************************