Taking Sharp Photos Using a 6x9 Folding Camera
 

RolandRB wrote:

This is why nearly all attempts to use a 6x9 folder fail
at this first hurdle - the camera was not up to the task. Very few
are.


Nice post and also the reasons I like the 6 X 4.5 folders better. The
6X9 chromes are nice but with the film flatness issues etc I get better
results from the smaller negs most of the time, especially when hand
holding the camera and shooting neg film. I've also found the models
that don't use front cell focusing work better for infinity shooting,
the front cell focusing models appear to be optimized for "portrait"
distances?

Stephanie

Taking Sharp Photos Using a 6x9 Folding Camera
 

wrote in message ...
RolandRB wrote:

This is why nearly all attempts to use a 6x9 folder fail
at this first hurdle - the camera was not up to the task. Very few
are.


Nice post and also the reasons I like the 6 X 4.5 folders better. The 6X9
chromes are nice but with the film flatness issues etc I get better
results from the smaller negs most of the time, especially when hand
holding the camera and shooting neg film. I've also found the models that
don't use front cell focusing work better for infinity shooting, the front
cell focusing models appear to be optimized for "portrait" distances?

Steph -

You can adjust the focus of those front cell focusing cameras yourself.
There used to be a fair number of websites explaining how to do this, but I
can't find them at the moment. aha - here is one such website. Click on
"focus adjustment."
http://www.rolandandcaroline.co.uk/repair.html

Taking Sharp Photos Using a 6x9 Folding Camera
 

Lawrence Akutagawa wrote:
wrote in message ...
RolandRB wrote:
This is why nearly all attempts to use a 6x9 folder fail
at this first hurdle - the camera was not up to the task. Very few
are.

Nice post and also the reasons I like the 6 X 4.5 folders better. The 6X9
chromes are nice but with the film flatness issues etc I get better
results from the smaller negs most of the time, especially when hand
holding the camera and shooting neg film. I've also found the models that
don't use front cell focusing work better for infinity shooting, the front
cell focusing models appear to be optimized for "portrait" distances?

Steph -

You can adjust the focus of those front cell focusing cameras yourself.
There used to be a fair number of websites explaining how to do this, but I
can't find them at the moment. aha - here is one such website. Click on
"focus adjustment."
http://www.rolandandcaroline.co.uk/repair.html



What I am talking about is optically these front cell focusing cameras
are a compromise, not that they need repair. They appear to be designed
to work best at medium distances and then use the shifting of the front
cell as a means of getting the focus at other distances acceptable. I've
found the models that use a helix or other means of moving the whole
lens assembly to produce sharper images at the ends of the focus range.

Stephanie

Taking Sharp Photos Using a 6x9 Folding Camera
 

wrote in message ...
Lawrence Akutagawa wrote:
wrote in message
...
RolandRB wrote:
This is why nearly all attempts to use a 6x9 folder fail
at this first hurdle - the camera was not up to the task. Very few
are.

Nice post and also the reasons I like the 6 X 4.5 folders better. The
6X9 chromes are nice but with the film flatness issues etc I get better
results from the smaller negs most of the time, especially when hand
holding the camera and shooting neg film. I've also found the models
that don't use front cell focusing work better for infinity shooting,
the front cell focusing models appear to be optimized for "portrait"
distances?

Steph -

You can adjust the focus of those front cell focusing cameras yourself.
There used to be a fair number of websites explaining how to do this, but
I can't find them at the moment. aha - here is one such website. Click
on "focus adjustment."
http://www.rolandandcaroline.co.uk/repair.html
What I am talking about is optically these front cell focusing cameras are
a compromise, not that they need repair. They appear to be designed to
work best at medium distances and then use the shifting of the front cell
as a means of getting the focus at other distances acceptable. I've found
the models that use a helix or other means of moving the whole lens
assembly to produce sharper images at the ends of the focus range.
.
mmm...I thought you were talking about the situation in which the camera
does not focus properly at infinity. I did not know you were talking about
a camera which focuses properly at infinity but not at other distances.

The implicit assumption made by the article that I cited is, of course, that
if the camera properly focuses at infinity, then it will also properly focus
at other distances. I would think that a camera focusing properly at
infinity but not at other distances suffers from some kind of serious that
requires the services of a good technician.

ummm..it is proper focus at different distances that we are talking about,
is it not?

Taking Sharp Photos Using a 6x9 Folding Camera
 

"RolandRB" wrote in message
...
On Mar 22, 11:18 pm, "Lawrence Akutagawa"
wrote:
wrote in
...
Lawrence Akutagawa wrote:
wrote in message
...
RolandRB wrote:
This is why nearly all attempts to use a 6x9 folder fail
at this first hurdle - the camera was not up to the task. Very few
are.

Nice post and also the reasons I like the 6 X 4.5 folders better. The
6X9 chromes are nice but with the film flatness issues etc I get
better
results from the smaller negs most of the time, especially when hand
holding the camera and shooting neg film. I've also found the models
that don't use front cell focusing work better for infinity shooting,
the front cell focusing models appear to be optimized for "portrait"
distances?

Steph -

You can adjust the focus of those front cell focusing cameras yourself.
There used to be a fair number of websites explaining how to do this,
but
I can't find them at the moment. aha - here is one such website. Click
on "focus adjustment."
http://www.rolandandcaroline.co.uk/repair.html
What I am talking about is optically these front cell focusing cameras
are
a compromise, not that they need repair. They appear to be designed to
work best at medium distances and then use the shifting of the front
cell
as a means of getting the focus at other distances acceptable. I've
found
the models that use a helix or other means of moving the whole lens
assembly to produce sharper images at the ends of the focus range.
.

mmm...I thought you were talking about the situation in which the camera
does not focus properly at infinity. I did not know you were talking about
a camera which focuses properly at infinity but not at other distances.

The implicit assumption made by the article that I cited is, of course,
that
if the camera properly focuses at infinity, then it will also properly
focus
at other distances. I would think that a camera focusing properly at
infinity but not at other distances suffers from some kind of serious that
requires the services of a good technician.

ummm..it is proper focus at different distances that we are talking about,
is it not?

It doesn't work like that. True macro lenses, for use at close
distance, have a more symmetrical design. For very close focussing
distances you can even get rings that allows you to reverse a standard
lens to give you better images. In other words, the design of the lens
is linked to the intended focussing distance. It could well be that
these front cell focussing lenses on folders are optimized to closer
distances and reach infinity as a compromise. However, moving a whole
lens that is more suitable for infinity won't give you best results at
closer distances. That is why front cell focussing is maybe not a bad
idea.

And for anyone who cares to try one of these old Tessars at infinity
focus then I can assure you that the results can be spectacular at
smaller f-stops.

***

Interesting point. I didn't realize that Stephanie was talking about
distances so close to the lens. Perhaps she can clarify the exact distances
of concern to her. Then perhaps someone with an optical background can
contribute to the discussion.

My personal experience is that the Tessar has served me very well at
whatever distance indicated by that distance scale, including infinity. But
no optical person am I.

hmm...a folder that allows its lens to be reversed just as a 35mm SLR does.
Now that one is new to me. Which folder has such a capability?

Taking Sharp Photos Using a 6x9 Folding Camera
 

Lawrence Akutagawa wrote:


Interesting point. I didn't realize that Stephanie was talking about
distances so close to the lens. Perhaps she can clarify the exact distances
of concern to her. Then perhaps someone with an optical background can
contribute to the discussion.

My personal experience is that the Tessar has served me very well at
whatever distance indicated by that distance scale, including infinity. But
no optical person am I.

hmm...a folder that allows its lens to be reversed just as a 35mm SLR does.
Now that one is new to me. Which folder has such a capability?



I'm not talking about "macro" distances. I'm talking about even if you
adjust these PERFECTLY at infinity, they are not as sharp as when you
then use the front cell to adjust the focus to a medium distance, say
4-5M or so.


The problem with these front cell focusing lenses is they are changing
the lens cell spacing from their optimal designed spacing as a cheaper
way of focusing the camera. This introduces optical problems that as
rolland noted can be corrected somewhat if you stop down the lens far
enough.

http://books.google.com/books?id=cuz...cusing&f=false


"The rearrangement of optical configuration introduces aberrations which
limit the largest image magnification possible"


This front cell focusing isn't an issue with contact prints, which is
what most of these were designed for. Moving the whole lens doesn't
change the optical configuration and is the way most lenses in medium
format and large format cameras do.

Here is another discussion of this issue.

http://photo.net/medium-format-photography-forum/004r7H

Stephanie

Taking Sharp Photos Using a 6x9 Folding Camera
 

wrote in message ...
Lawrence Akutagawa wrote:


Interesting point. I didn't realize that Stephanie was talking about
distances so close to the lens. Perhaps she can clarify the exact
distances of concern to her. Then perhaps someone with an optical
background can contribute to the discussion.

My personal experience is that the Tessar has served me very well at
whatever distance indicated by that distance scale, including infinity.
But no optical person am I.

hmm...a folder that allows its lens to be reversed just as a 35mm SLR
does. Now that one is new to me. Which folder has such a capability?
I'm not talking about "macro" distances. I'm talking about even if you
adjust these PERFECTLY at infinity, they are not as sharp as when you then
use the front cell to adjust the focus to a medium distance, say 4-5M or
so.

The problem with these front cell focusing lenses is they are changing the
lens cell spacing from their optimal designed spacing as a cheaper way of
focusing the camera. This introduces optical problems that as rolland
noted can be corrected somewhat if you stop down the lens far enough.

http://books.google.com/books?id=cuz...cusing&f=false


"The rearrangement of optical configuration introduces aberrations which
limit the largest image magnification possible"


This front cell focusing isn't an issue with contact prints, which is what
most of these were designed for. Moving the whole lens doesn't change the
optical configuration and is the way most lenses in medium format and
large format cameras do.

Here is another discussion of this issue.

http://photo.net/medium-format-photography-forum/004r7H

I see. Here is an article which addresses the situation from the factory
setting perspective:

http://reviews.ebay.co.uk/Medium-for...00000000915733

Taking Sharp Photos Using a 6x9 Folding Camera
 

Lawrence Akutagawa wrote:
wrote in message ...


I see. Here is an article which addresses the situation from the factory
setting perspective:

http://reviews.ebay.co.uk/Medium-for...00000000915733



Again they are just talking about setting infinity to get it as good as
it can be. No doubt that should be checked if you shoot things at infinity.

The problem I'm talking about is at infinity, because the cell spacing
(instead of the lens to film distance) was moved to adjust focus, the
Spherical Abberation is overcorrected, which is helped by stopping down
the lens. At f16 no doubt they can take sharp images but this isn't a
problem with a camera that moves the whole lens/shutter assembly. And
ultimately these other types will produce even sharper images.

This is another discussion of this on a front cell focusing TLR.

http://photo.net/classic-cameras-forum/00CQPp

No doubt a front cell focusing tessar lensed camera can make great
images, but I've found a couple of older models that use a moving bed
focusing tessar to be even better. The only problem is these older ones
have uncoated lenses so you have to be careful to not have flare issues.

Stephanie

Taking Sharp Photos Using a 6x9 Folding Camera
 

wrote in message ...
Lawrence Akutagawa wrote:
wrote in message
...


I see. Here is an article which addresses the situation from the factory
setting perspective:

http://reviews.ebay.co.uk/Medium-for...00000000915733

Again they are just talking about setting infinity to get it as good as it
can be. No doubt that should be checked if you shoot things at infinity.

The problem I'm talking about is at infinity, because the cell spacing
(instead of the lens to film distance) was moved to adjust focus, the
Spherical Abberation is overcorrected, which is helped by stopping down
the lens. At f16 no doubt they can take sharp images but this isn't a
problem with a camera that moves the whole lens/shutter assembly. And
ultimately these other types will produce even sharper images.

This is another discussion of this on a front cell focusing TLR.

http://photo.net/classic-cameras-forum/00CQPp

No doubt a front cell focusing tessar lensed camera can make great images,
but I've found a couple of older models that use a moving bed focusing
tessar to be even better. The only problem is these older ones have
uncoated lenses so you have to be careful to not have flare issues.

Stephanie -

hmm...my reading of the article that I cited does not talk about setting at
infinity, but at 10 feet. Are you and I reading the same article?

Taking Sharp Photos Using a 6x9 Folding Camera
 

Lawrence Akutagawa wrote:
wrote in message ...
Lawrence Akutagawa wrote:
wrote in message
...
I see. Here is an article which addresses the situation from the factory
setting perspective:

http://reviews.ebay.co.uk/Medium-for...00000000915733
Again they are just talking about setting infinity to get it as good as it
can be. No doubt that should be checked if you shoot things at infinity.

The problem I'm talking about is at infinity, because the cell spacing
(instead of the lens to film distance) was moved to adjust focus, the
Spherical Abberation is overcorrected, which is helped by stopping down
the lens. At f16 no doubt they can take sharp images but this isn't a
problem with a camera that moves the whole lens/shutter assembly. And
ultimately these other types will produce even sharper images.

This is another discussion of this on a front cell focusing TLR.

http://photo.net/classic-cameras-forum/00CQPp

No doubt a front cell focusing tessar lensed camera can make great images,
but I've found a couple of older models that use a moving bed focusing
tessar to be even better. The only problem is these older ones have
uncoated lenses so you have to be careful to not have flare issues.

Stephanie -

hmm...my reading of the article that I cited does not talk about setting at
infinity, but at 10 feet. Are you and I reading the same article?




Again this issue I am talking about is NOT about adjusting focus. No
matter what procedure you use to "repair" an out of focus front cell
focusing camera or how perfectly the camera is focused, you still have
over and under corrected Spherical Abberations induced by changing the
cell spacing to focus at other that the "designed cell spacing focus"
the camera was manufactured to (which is usually the middle of the focus
range) which ALWAYS degrades image quality.

Stopping down the lens helps this problem which makes these types still
usable. But they are at their best in the middle of the focus range, a
moving bed camera will NOT have this limitation.


Stephanie