Discussion:
Taking Sharp Photos Using a 6x9 Folding Camera
(too old to reply)
RolandRB
2010-03-20 16:07:24 UTC
Permalink
Taking Sharp Photos Using a 6x9 Folding Camera

Author: Roland Rashleigh-Berry
Version: Draft 1.0
Date: 20 March 2010

Introduction

Those of you who still use film cameras might from time to time
consider the option of using a 6x9 folding camera. Here you have a
large film area (6cm x 9cm) with the associated possibility of
capturing a great deal of detail, combined with the convenience of
being able to fit the camera in a large pocket. Many people have tried
this but are disappointed with the results and give up on the idea.
There are good reasons why it is difficult to get good results but it
is possible if you follow some guidelines. These will be described
here.

Contact Prints

Folding cameras were fashionable at the time of black and white film
(that was not sensitive to red light) and prints were contact prints.
In other words, the black and white picture that was the end result
was made by shining light through the film negative onto photographic
paper. The final photo was the same size as the film area so these
folders were not designed with enlargement in mind. If you intend to
use a 6x9 folding camera then you probably will want to enlarge the
photo to show up the detail you wish to capture so you should realize
that you are going to make use of the camera beyond its design limits.
This means you need an exceptional folder that is capable of
enlargement. 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.

The Three Requirements

What is needed from a 6x9 folding camera to allow enlargements to be
made is a good lens, a fairly firm pressure plate to hold the film
flat and a firm "standard" such that when the camera is extended, the
lens is held rigidly in place. Assuming the camera is mechanically
sound then these are the three main requirements. This limits the
choice of camera and the only make of camera I am aware of that meets
these three criteria are the Zeiss 6x9 folding cameras with the Tessar
lens. There are other notable cameras, such as the Vöigtlander Bessa
camera with the Color Skopar lens or the better Heliar lens but in the
case of the Bessa II the standard that holds the lens in place often
has slack in it which causes blur when the photograph is taken an the
lens was never as sharp as the Tessar in any case, perhaps due to lack
of manufacturing precision rather than lens design. In fact the older
pre-WWII Tessar lenses designed for black and white film produce
better results than the Color Skopar designed for color film. This
could explain why Zeiss never felt the need to make folders with an
upgraded lens design to compete with its rivals (although the Tessar
lens was redesigned a few times over its history to improve its
performance).

The Zeiss 6x9 folding cameras

You will have to take it on trust from me that if you want to take
sharp photos capable of enlargement with a 6x9 folder then the only
sensible option is to use a Zeiss 6x9 folder. Deviation from this will
almost certainly result in failure. But apart from making sure the
Zeiss folder is in sound mechanical condition and the lens in good
condition, there are other guidelines that need to be followed.

Wind on just before taking the photo

You need the film to be as flat as possible. The film will be flattest
a few seconds just after being wound on so you should wind on just
before taking the photograph and wait just a few seconds for the film
to flatten further. If you delay taking the shot for whatever reason
then retighten the film by using the wind-on knob without actually
advancing the film.

Use f11 to f16

Even with taking care to ensure the film is flat, there is still some
unevenness in the film surface. You need to use a small enough
aperture to give you enough depth of focus to ensure the full surface
of the film receives a sharp image. This limits you to apertures
between f11 and f16 inclusive. Any fractional values between these
limits are of course possible.

Use 1/200th sec film speed or faster for hand-held shots

6x9 folding cameras are difficult to hold steady when taking the shot.
The focal length of the lens will typically be 105mm so to ensure a
reasonable chance of taking a sharp photo then you will have to use an
exposure time of 1/150th second or faster so you have to ensure that
this sort of shutter speed is available on whatever Zeiss camera you
choose. Most Compur shutters that many of the better Zeiss cameras
have will have a 1/150th sec or a 1/200th sec shutter speed available.
Note that most Compur shutters have an even faster speed such as
1/400th sec or 1/500th sec. The trouble is that to achieve these
speeds a stronger spring is used and this can create extra camera
shake that negates the speed advantage when taking hand-held shots.

Use a monopod

Even using the faster shutter speeds will not ensure all your pictures
are sharp. Even with a good technique, some of the shots will be
blurred due to camera shake. You will get much better results if you
can support the camera. A monopod will help enormously. This makes
carrying the camera less convenient but you might be carrying it as a
second camera and you might benefit from using a monopod for the
primary camera.

Bright sunny weather

If your aim is to capture a lot of detail in color then you will
probably opt to use a slow film speed such as ISO 100. Using the
"Sunny 16 rule" then for subjects front-lit by the sun, at f16 the
exposure should be the inverse of the film speed. So at f16, using ISO
100 film, exposure should be 1/100th sec. But this is too slow for
hand-held shots with a 6x9 folder so the equivalent at f11 is to use a
1/200th sec film speed for ISO 100 film. So for taking sharp hand-held
shots using 100 speed film you are limited to sunny conditions with
your subject front-lit by the sun using an aperture of f11 and a
shutter speed of 1/200th second (1/150th sec is also good).

Focussing and Depth of Field

It is important to use the correct focal distance. If possible, you
should set the focus to the exact distance. If your subject is at
infinity for landscape shots then set the focus to infinity and not
some marking on the lens that is supposed to be good for all long
distances. These marking were only good for contact printing. If you
require some depth of field then do not use the markings on the lens
as your guide as again, these are for contact print size. For f11 you
should use the markings for two stops more open at least. Preferably
three. So for f11 use the d-o-f markings for f5.6 or f4 if you can get
away with it.

Conclusion

Follow the guidelines above and you will be able to take sharp photos
with your Zeiss 6x9 folder that are capable of enlargement of maybe up
to 8x. Viewing these images made with color slide film on a light
table and an 8x loupe can be very satisfying. I want to end with a few
practical tips on using these old cameras. If your camera has a red
window in the back that can not be covered using a twist knob then you
will have to use a piece of black insulating tape for this purpose
that you can peel back to see the film frame numbers. Winding on film
should always be done in subdued light otherwise the light that is
making the frame numbers visible will also fog the film. Folders have
poor light seals so you should aim to finish a roll within a few days
of starting it and between use the camera should be stored in a dark
place. If you intend to leave the roll unfinished for more than a week
then wind on an extra frame and waste that frame so that less light
leaks onto the last good frame you took. Old cameras will allow double
exposure so don't become so engrossed in the technicalities that you
forget to wind on the film before taking the shot.
RolandRB
2010-03-21 07:25:27 UTC
Permalink
Post by RolandRB
Taking Sharp Photos Using a 6x9 Folding Camera
Author: Roland Rashleigh-Berry
Version: Draft 1.0
Date: 20 March 2010
If anyone wants to web this I can send them the latest version as an
RTF file.

I could make some scans of images I have taken with a 1933 Zeiss
camera but these files will be very large and my scanner is only an
Epson 4990 so they won't be of high quality.
Alan Browne
2010-03-21 15:41:18 UTC
Permalink
Post by RolandRB
Taking Sharp Photos Using a 6x9 Folding Camera
Author: Roland Rashleigh-Berry
Version: Draft 1.0
Date: 20 March 2010
I was tempted last year (or so) to buy a 6x9 folder, others 'round here
like Littleboy are fans. They also warn about focus issues with some
6x9 folders, so it's not something I'd jump into lightly. Esp. in light
of the ever reducing processing availability/convenience.

There is a new FujiFilm 6x9 folder, but it isn't cheap by any measure.
I'd put my photo-bucks elsewhere.
--
gmail originated posts are filtered due to spam.
RolandRB
2010-03-21 17:06:27 UTC
Permalink
Post by Alan Browne
Post by RolandRB
Taking Sharp Photos Using a 6x9 Folding Camera
Author: Roland Rashleigh-Berry
Version: Draft 1.0
Date: 20 March 2010
I was tempted last year (or so) to buy a 6x9 folder, others 'round here
like Littleboy are fans.  They also warn about focus issues with some
6x9 folders, so it's not something I'd jump into lightly.  Esp. in light
of the ever reducing processing availability/convenience.
There is a new FujiFilm 6x9 folder, but it isn't cheap by any measure.
I'd put my photo-bucks elsewhere.
--
gmail originated posts are filtered due to spam.
The only recent FujiFilm folding camera I am aware of is a 6x7
(GF670). Film flatness is much less of a problem with thee smaller
formats such as 6x6 folding cameras but it is the 6x9 format I like.
It's altogether more impressive on a light box.
Alan Browne
2010-03-21 17:29:54 UTC
Permalink
Post by RolandRB
Post by Alan Browne
Post by RolandRB
Taking Sharp Photos Using a 6x9 Folding Camera
Author: Roland Rashleigh-Berry
Version: Draft 1.0
Date: 20 March 2010
I was tempted last year (or so) to buy a 6x9 folder, others 'round here
like Littleboy are fans. They also warn about focus issues with some
6x9 folders, so it's not something I'd jump into lightly. Esp. in light
of the ever reducing processing availability/convenience.
There is a new FujiFilm 6x9 folder, but it isn't cheap by any measure.
I'd put my photo-bucks elsewhere.
--
gmail originated posts are filtered due to spam.
The only recent FujiFilm folding camera I am aware of is a 6x7
(GF670). Film flatness is much less of a problem with thee smaller
formats such as 6x6 folding cameras but it is the 6x9 format I like.
It's altogether more impressive on a light box.
Doh! Still just as tempting for the same reasons.
--
gmail originated posts are filtered due to spam.
s***@yahoo.com
2010-03-22 05:49:11 UTC
Permalink
This post might be inappropriate. Click to display it.
Lawrence Akutagawa
2010-03-22 07:31:49 UTC
Permalink
Post by RolandRB
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
s***@yahoo.com
2010-03-22 21:23:16 UTC
Permalink
Post by Lawrence Akutagawa
Post by RolandRB
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
Lawrence Akutagawa
2010-03-22 22:18:25 UTC
Permalink
Post by Lawrence Akutagawa
Post by s***@yahoo.com
Post by RolandRB
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?
RolandRB
2010-03-23 07:13:25 UTC
Permalink
Post by Lawrence Akutagawa
Post by Lawrence Akutagawa
Post by s***@yahoo.com
Post by RolandRB
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.
Lawrence Akutagawa
2010-03-23 14:36:06 UTC
Permalink
Post by Lawrence Akutagawa
Post by Lawrence Akutagawa
Post by s***@yahoo.com
Post by RolandRB
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?
s***@yahoo.com
2010-03-24 05:48:49 UTC
Permalink
Post by Lawrence Akutagawa
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=cuzYl4hx-B8C&pg=PA195&lpg=PA195&dq=front+cell+focusing&source=bl&ots=n-MxySGxJI&sig=YauQ-9Cx0_9db_3kCUL-FIZgPPw&hl=en&ei=w6WpS_SDCYL58Abv7Pi7Bw&sa=X&oi=book_result&ct=result&resnum=2&ved=0CAgQ6AEwAQ#v=onepage&q=front%20cell%20focusing&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
Lawrence Akutagawa
2010-03-24 06:47:04 UTC
Permalink
Post by s***@yahoo.com
Post by Lawrence Akutagawa
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=cuzYl4hx-B8C&pg=PA195&lpg=PA195&dq=front+cell+focusing&source=bl&ots=n-MxySGxJI&sig=YauQ-9Cx0_9db_3kCUL-FIZgPPw&hl=en&ei=w6WpS_SDCYL58Abv7Pi7Bw&sa=X&oi=book_result&ct=result&resnum=2&ved=0CAgQ6AEwAQ#v=onepage&q=front%20cell%20focusing&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-format-focus-on-better-definition_W0QQugidZ10000000000915733
s***@yahoo.com
2010-03-24 07:13:49 UTC
Permalink
Post by Lawrence Akutagawa
I see. Here is an article which addresses the situation from the factory
http://reviews.ebay.co.uk/Medium-format-focus-on-better-definition_W0QQugidZ10000000000915733
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
Lawrence Akutagawa
2010-03-24 08:21:23 UTC
Permalink
Post by Lawrence Akutagawa
I see. Here is an article which addresses the situation from the factory
http://reviews.ebay.co.uk/Medium-format-focus-on-better-definition_W0QQugidZ10000000000915733
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?
s***@yahoo.com
2010-03-24 16:57:28 UTC
Permalink
Post by Lawrence Akutagawa
Post by Lawrence Akutagawa
I see. Here is an article which addresses the situation from the factory
http://reviews.ebay.co.uk/Medium-format-focus-on-better-definition_W0QQugidZ10000000000915733
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
Max Perl
2010-03-27 21:44:51 UTC
Permalink
"RolandRB" <***@hotmail.com> skrev i en meddelelse news:2a79eb0f-1331-4643-a969-***@q15g2000yqj.googlegroups.com...
Taking Sharp Photos Using a 6x9 Folding Camera

Author: Roland Rashleigh-Berry
Version: Draft 1.0
Date: 20 March 2010

Introduction

Those of you who still use film cameras might from time to time
consider the option of using a 6x9 folding camera. Here you have a
large film area (6cm x 9cm) with the associated possibility of
capturing a great deal of detail, combined with the convenience of
being able to fit the camera in a large pocket. Many people have tried
this but are disappointed with the results and give up on the idea.
There are good reasons why it is difficult to get good results but it
is possible if you follow some guidelines. These will be described
here.

Contact Prints

Folding cameras were fashionable at the time of black and white film
(that was not sensitive to red light) and prints were contact prints.
In other words, the black and white picture that was the end result
was made by shining light through the film negative onto photographic
paper. The final photo was the same size as the film area so these
folders were not designed with enlargement in mind. If you intend to
use a 6x9 folding camera then you probably will want to enlarge the
photo to show up the detail you wish to capture so you should realize
that you are going to make use of the camera beyond its design limits.
This means you need an exceptional folder that is capable of
enlargement. 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.

The Three Requirements

What is needed from a 6x9 folding camera to allow enlargements to be
made is a good lens, a fairly firm pressure plate to hold the film
flat and a firm "standard" such that when the camera is extended, the
lens is held rigidly in place. Assuming the camera is mechanically
sound then these are the three main requirements. This limits the
choice of camera and the only make of camera I am aware of that meets
these three criteria are the Zeiss 6x9 folding cameras with the Tessar
lens. There are other notable cameras, such as the Vöigtlander Bessa
camera with the Color Skopar lens or the better Heliar lens but in the
case of the Bessa II the standard that holds the lens in place often
has slack in it which causes blur when the photograph is taken an the
lens was never as sharp as the Tessar in any case, perhaps due to lack
of manufacturing precision rather than lens design. In fact the older
pre-WWII Tessar lenses designed for black and white film produce
better results than the Color Skopar designed for color film. This
could explain why Zeiss never felt the need to make folders with an
upgraded lens design to compete with its rivals (although the Tessar
lens was redesigned a few times over its history to improve its
performance).

The Zeiss 6x9 folding cameras

You will have to take it on trust from me that if you want to take
sharp photos capable of enlargement with a 6x9 folder then the only
sensible option is to use a Zeiss 6x9 folder. Deviation from this will
almost certainly result in failure. But apart from making sure the
Zeiss folder is in sound mechanical condition and the lens in good
condition, there are other guidelines that need to be followed.

Wind on just before taking the photo

You need the film to be as flat as possible. The film will be flattest
a few seconds just after being wound on so you should wind on just
before taking the photograph and wait just a few seconds for the film
to flatten further. If you delay taking the shot for whatever reason
then retighten the film by using the wind-on knob without actually
advancing the film.

Use f11 to f16

Even with taking care to ensure the film is flat, there is still some
unevenness in the film surface. You need to use a small enough
aperture to give you enough depth of focus to ensure the full surface
of the film receives a sharp image. This limits you to apertures
between f11 and f16 inclusive. Any fractional values between these
limits are of course possible.

Use 1/200th sec film speed or faster for hand-held shots

6x9 folding cameras are difficult to hold steady when taking the shot.
The focal length of the lens will typically be 105mm so to ensure a
reasonable chance of taking a sharp photo then you will have to use an
exposure time of 1/150th second or faster so you have to ensure that
this sort of shutter speed is available on whatever Zeiss camera you
choose. Most Compur shutters that many of the better Zeiss cameras
have will have a 1/150th sec or a 1/200th sec shutter speed available.
Note that most Compur shutters have an even faster speed such as
1/400th sec or 1/500th sec. The trouble is that to achieve these
speeds a stronger spring is used and this can create extra camera
shake that negates the speed advantage when taking hand-held shots.

Use a monopod

Even using the faster shutter speeds will not ensure all your pictures
are sharp. Even with a good technique, some of the shots will be
blurred due to camera shake. You will get much better results if you
can support the camera. A monopod will help enormously. This makes
carrying the camera less convenient but you might be carrying it as a
second camera and you might benefit from using a monopod for the
primary camera.

Bright sunny weather

If your aim is to capture a lot of detail in color then you will
probably opt to use a slow film speed such as ISO 100. Using the
"Sunny 16 rule" then for subjects front-lit by the sun, at f16 the
exposure should be the inverse of the film speed. So at f16, using ISO
100 film, exposure should be 1/100th sec. But this is too slow for
hand-held shots with a 6x9 folder so the equivalent at f11 is to use a
1/200th sec film speed for ISO 100 film. So for taking sharp hand-held
shots using 100 speed film you are limited to sunny conditions with
your subject front-lit by the sun using an aperture of f11 and a
shutter speed of 1/200th second (1/150th sec is also good).

Focussing and Depth of Field

It is important to use the correct focal distance. If possible, you
should set the focus to the exact distance. If your subject is at
infinity for landscape shots then set the focus to infinity and not
some marking on the lens that is supposed to be good for all long
distances. These marking were only good for contact printing. If you
require some depth of field then do not use the markings on the lens
as your guide as again, these are for contact print size. For f11 you
should use the markings for two stops more open at least. Preferably
three. So for f11 use the d-o-f markings for f5.6 or f4 if you can get
away with it.

Conclusion

Follow the guidelines above and you will be able to take sharp photos
with your Zeiss 6x9 folder that are capable of enlargement of maybe up
to 8x. Viewing these images made with color slide film on a light
table and an 8x loupe can be very satisfying. I want to end with a few
practical tips on using these old cameras. If your camera has a red
window in the back that can not be covered using a twist knob then you
will have to use a piece of black insulating tape for this purpose
that you can peel back to see the film frame numbers. Winding on film
should always be done in subdued light otherwise the light that is
making the frame numbers visible will also fog the film. Folders have
poor light seals so you should aim to finish a roll within a few days
of starting it and between use the camera should be stored in a dark
place. If you intend to leave the roll unfinished for more than a week
then wind on an extra frame and waste that frame so that less light
leaks onto the last good frame you took. Old cameras will allow double
exposure so don't become so engrossed in the technicalities that you
forget to wind on the film before taking the shot.
******************************************************

I agree with most of your post. I have some personal experiences by not
getting
the quality out of the 6x9 folders I expected. E.g. the Bessa II with
Color-Heliar
and Color-Skopar. I sent the Bessa II with Color-Heliar to a pro which did
some
adjustments of the lens. It was both focus and alignment of the lens done by
using
a "collimator". The front standard may still be a little problem....a bit of
a design flaw
when these folders gets used a lot. The Bessa I's locks the front standard
much better
into position. But after the adjustments the Bessa II was able to take much
sharper
images than before. Think the lens is too good to be put on a folder it
should be put
on a Linhof lens board instead an used on a Technika. But here is a test
image
on a 400 CN film.

http://www.pbase.com/mxp/image/121325884/original

...and 100% crop of above image (4000 dpi scan):
http://www.pbase.com/mxp/image/121326005/original
K W Hart
2010-03-28 22:50:19 UTC
Permalink
Post by RolandRB
Taking Sharp Photos Using a 6x9 Folding Camera
Author: Roland Rashleigh-Berry
Version: Draft 1.0
Date: 20 March 2010
Introduction
Those of you who still use film cameras might from time to time
consider the option of using a 6x9 folding camera. Here you have a
large film area (6cm x 9cm) with the associated possibility of
capturing a great deal of detail, combined with the convenience of
being able to fit the camera in a large pocket. Many people have tried
this but are disappointed with the results and give up on the idea.
There are good reasons why it is difficult to get good results but it
is possible if you follow some guidelines. These will be described
here.
snip
Post by RolandRB
Wind on just before taking the photo
You need the film to be as flat as possible. The film will be flattest
a few seconds just after being wound on so you should wind on just
before taking the photograph and wait just a few seconds for the film
to flatten further. If you delay taking the shot for whatever reason
then retighten the film by using the wind-on knob without actually
advancing the film.
snip

I don't understand the reasoning here. If you wind the film just before
shooting, the film is going to be just coming off the roll. On the other
hand, if you wind the film and allow it to 'rest' in the film exposure
plane, it will tend to lose it's curl over time.
I've purchased used cameras that had film left in them for a long period of
time. The film would have a uniform curl except where it rested in the film
plane- that part of the film would be fairly flat. It seems to me that for
the flattest film, you should wind it until the film is in position for
exposure, and put the camera away for a year or two before taking a picture.
This should give the flattest film in the film exposure area, and also
conserve film.
Alan Browne
2010-03-29 00:52:04 UTC
Permalink
Post by K W Hart
Post by RolandRB
Wind on just before taking the photo
You need the film to be as flat as possible. The film will be flattest
a few seconds just after being wound on so you should wind on just
before taking the photograph and wait just a few seconds for the film
to flatten further. If you delay taking the shot for whatever reason
then retighten the film by using the wind-on knob without actually
advancing the film.
snip
I don't understand the reasoning here. If you wind the film just before
shooting, the film is going to be just coming off the roll. On the other
hand, if you wind the film and allow it to 'rest' in the film exposure
plane, it will tend to lose it's curl over time.
I think the notion is that nothing in the camera relaxes after winding
and lets the film bow.
--
gmail originated posts are filtered due to spam.
RolandRB
2010-03-29 05:40:26 UTC
Permalink
Post by K W Hart
Post by RolandRB
Taking Sharp Photos Using a 6x9 Folding Camera
Author: Roland Rashleigh-Berry
Version: Draft 1.0
Date: 20 March 2010
Introduction
Those of you who still use film cameras might from time to time
consider the option of using a 6x9 folding camera. Here you have a
large film area (6cm x 9cm) with the associated possibility of
capturing a great deal of detail, combined with the convenience of
being able to fit the camera in a large pocket. Many people have tried
this but are disappointed with the results and give up on the idea.
There are good reasons why it is difficult to get good results but it
is possible if you follow some guidelines. These will be described
here.
snip
Post by RolandRB
Wind on just before taking the photo
You need the film to be as flat as possible. The film will be flattest
a few seconds just after being wound on so you should wind on just
before taking the photograph and wait just a few seconds for the film
to flatten further. If you delay taking the shot for whatever reason
then retighten the film by using the wind-on knob without actually
advancing the film.
snip
I don't understand the reasoning here. If you wind the film just before
shooting, the film is going to be just coming off the roll. On the other
hand, if you wind the film and allow it to 'rest' in the film exposure
plane, it will tend to lose it's curl over time.
I've purchased used cameras that had film left in them for a long period of
time. The film would have a uniform curl except where it rested in the film
plane- that part of the film would be fairly flat. It seems to me that for
the flattest film, you should wind it until the film is in position for
exposure, and put the camera away for a year or two before taking a picture.
This should give the flattest film in the film exposure area, and also
conserve film.
You wouldn't even have to bother exposing the film if you did that.
Folders have very poor light seals.

Continue reading on narkive:
Loading...