Knoppow on Kalert RF

This stuff works fine and is the right thickness. The
piece costs about $15 US and is enough to make several
mirrors.
I've meant to write a procedure for replacing it to
supplement the one already on the Graflex.org site. That one
says you must break out the old mirror. This is not so. the
mirror is held by two spring clips but it has some wax like
material to cement it. This can be removed by using a little
acetone or even lighter fluid. The clips are removed
carefully because you will reuse them. Note how they are
oriented. Use the old mirror as a pattern to cut the new
one. Use a carbide scribe to mark the glass, it will snap at
the scratch. I got my scribe at Home Depot for $5 US. This
is also the right tool to use for ground glass.
Its much easier to remove the old mirror and replace it if
you remove the entire mirror assembly. However, once its
remounted you must make sure the mirror is at an exactly 45
degree angle. A small drafting triangle will work for this.
When the mirror is replaced place a drop of cement at the
corners to make sure it doesn't drift with time. Airplane
glue works fine and is easily removed if you have to. If the
mirror is cut accurately it will just drop in.
The coated surface of the mirror must fact the eye window
of the rangefinder. Because it is a 50%-%50% splitter is
difficult to see which side the mirror is on. However, this
can be done by looking at the reflection of a small light
placed near the mirror. When the mirror is facing you light
must travel through the mirror coating twice to be refected
by the inside surface of the glass so the second reflection
will be much dimmer when viewed this way. The other way the
two reflections will be nearly equal in strength. If the
mirror is placed backward it will throw all the adjustments
way off plus it may result in a double reflection.
Once the mirror is mounted the mirror assembly is
replaced (held by one screw) and adjusted for 45 degree
angle. Then you will probably have to readjust everything
although you may be lucky. Start with the lateral
coincidence adjustment. I've posted instructions on setting
up Kalart rangefinders to the Graflex.org site, but again
want to post a revised and clarified version. The key is to
get the infinity adjustments right to begin with. This
involves making sure the actuating arm is set right and the
initial infinity setting of the lens frame are correct. On
Speed and Crown Graphics using the Kalart the infinity stops
should be set so that the camera must be racked out perhaps
1/16th inch from the mechanical stop. I recently posted a
letter to the Graflex.org help board in the Speed Graphic
section on how to set the actuating arm correctly.
Faded beam splitter mirrors seem to be very common on
Graphics of a certain age. I don't know what happens to
them. Fortunately, they are easy to replace and once done
will probably never have to be done again.
A makeshift fix is to place a neutral or colored filter
over the upper window of the RF. This will increase the
contrast of the two images although it is no substitute for
replacing the beam splitter.

There is no eyepiece on the rangfinder but most came with
a plain tube to shield image. This was not supplied on all
Graphics or it may be missing. Some RFs have coarse threads
in the eyepiece for this to thread into, some have a bracket
on the back of the camera in line with the eye window of the
RF for this tube.
There were also telescopes made to fit the Kalart. One
was made by Kalart but there were others. I've never managed
to find one. A telescope on the eye window has the effect of
having a greater base distance for the rangefinder and thus
increasing its accuracy. Back when the Contax camera came
out to compete with Leica it advertised it had a greater RF
base so was more accurate. The Leica, however, had a 2X
telescope built in so the _effective_ base of the two was
about the same.
The Kalart is very accurate when set up correctly.
Correct set up is tedious but once done will not have to be
done again unless the lens is changed.

Sorry folks, I was just sending Richard's directions to myself but
forgot to delete the news group address.

Jim

Jim Hemenway wrote:

This stuff works fine and is the right thickness. The
piece costs about $15 US and is enough to make several
mirrors.
I've meant to write a procedure for replacing it to
supplement the one already on the Graflex.org site. That one
says you must break out the old mirror. This is not so. the
mirror is held by two spring clips but it has some wax like
material to cement it. This can be removed by using a little
acetone or even lighter fluid. The clips are removed
carefully because you will reuse them. Note how they are
oriented. Use the old mirror as a pattern to cut the new
one. Use a carbide scribe to mark the glass, it will snap at
the scratch. I got my scribe at Home Depot for $5 US. This
is also the right tool to use for ground glass.
Its much easier to remove the old mirror and replace it if
you remove the entire mirror assembly. However, once its
remounted you must make sure the mirror is at an exactly 45
degree angle. A small drafting triangle will work for this.
When the mirror is replaced place a drop of cement at the
corners to make sure it doesn't drift with time. Airplane
glue works fine and is easily removed if you have to. If the
mirror is cut accurately it will just drop in.
The coated surface of the mirror must fact the eye window
of the rangefinder. Because it is a 50%-%50% splitter is
difficult to see which side the mirror is on. However, this
can be done by looking at the reflection of a small light
placed near the mirror. When the mirror is facing you light
must travel through the mirror coating twice to be refected
by the inside surface of the glass so the second reflection
will be much dimmer when viewed this way. The other way the
two reflections will be nearly equal in strength. If the
mirror is placed backward it will throw all the adjustments
way off plus it may result in a double reflection.
Once the mirror is mounted the mirror assembly is
replaced (held by one screw) and adjusted for 45 degree
angle. Then you will probably have to readjust everything
although you may be lucky. Start with the lateral
coincidence adjustment. I've posted instructions on setting
up Kalart rangefinders to the Graflex.org site, but again
want to post a revised and clarified version. The key is to
get the infinity adjustments right to begin with. This
involves making sure the actuating arm is set right and the
initial infinity setting of the lens frame are correct. On
Speed and Crown Graphics using the Kalart the infinity stops
should be set so that the camera must be racked out perhaps
1/16th inch from the mechanical stop. I recently posted a
letter to the Graflex.org help board in the Speed Graphic
section on how to set the actuating arm correctly.
Faded beam splitter mirrors seem to be very common on
Graphics of a certain age. I don't know what happens to
them. Fortunately, they are easy to replace and once done
will probably never have to be done again.
A makeshift fix is to place a neutral or colored filter
over the upper window of the RF. This will increase the
contrast of the two images although it is no substitute for
replacing the beam splitter.

There is no eyepiece on the rangfinder but most came with
a plain tube to shield image. This was not supplied on all
Graphics or it may be missing. Some RFs have coarse threads
in the eyepiece for this to thread into, some have a bracket
on the back of the camera in line with the eye window of the
RF for this tube.
There were also telescopes made to fit the Kalart. One
was made by Kalart but there were others. I've never managed
to find one. A telescope on the eye window has the effect of
having a greater base distance for the rangefinder and thus
increasing its accuracy. Back when the Contax camera came
out to compete with Leica it advertised it had a greater RF
base so was more accurate. The Leica, however, had a 2X
telescope built in so the _effective_ base of the two was
about the same.
The Kalart is very accurate when set up correctly.
Correct set up is tedious but once done will not have to be
done again unless the lens is changed.

Sorry folks, I was just sending Richard's directions to myself but
forgot to delete the news group address.

Jim

Jim Hemenway wrote:

This stuff works fine and is the right thickness. The
piece costs about $15 US and is enough to make several
mirrors.
I've meant to write a procedure for replacing it to
supplement the one already on the Graflex.org site. That one
says you must break out the old mirror. This is not so. the
mirror is held by two spring clips but it has some wax like
material to cement it. This can be removed by using a little
acetone or even lighter fluid. The clips are removed
carefully because you will reuse them. Note how they are
oriented. Use the old mirror as a pattern to cut the new
one. Use a carbide scribe to mark the glass, it will snap at
the scratch. I got my scribe at Home Depot for $5 US. This
is also the right tool to use for ground glass.
Its much easier to remove the old mirror and replace it if
you remove the entire mirror assembly. However, once its
remounted you must make sure the mirror is at an exactly 45
degree angle. A small drafting triangle will work for this.
When the mirror is replaced place a drop of cement at the
corners to make sure it doesn't drift with time. Airplane
glue works fine and is easily removed if you have to. If the
mirror is cut accurately it will just drop in.
The coated surface of the mirror must fact the eye window
of the rangefinder. Because it is a 50%-%50% splitter is
difficult to see which side the mirror is on. However, this
can be done by looking at the reflection of a small light
placed near the mirror. When the mirror is facing you light
must travel through the mirror coating twice to be refected
by the inside surface of the glass so the second reflection
will be much dimmer when viewed this way. The other way the
two reflections will be nearly equal in strength. If the
mirror is placed backward it will throw all the adjustments
way off plus it may result in a double reflection.
Once the mirror is mounted the mirror assembly is
replaced (held by one screw) and adjusted for 45 degree
angle. Then you will probably have to readjust everything
although you may be lucky. Start with the lateral
coincidence adjustment. I've posted instructions on setting
up Kalart rangefinders to the Graflex.org site, but again
want to post a revised and clarified version. The key is to
get the infinity adjustments right to begin with. This
involves making sure the actuating arm is set right and the
initial infinity setting of the lens frame are correct. On
Speed and Crown Graphics using the Kalart the infinity stops
should be set so that the camera must be racked out perhaps
1/16th inch from the mechanical stop. I recently posted a
letter to the Graflex.org help board in the Speed Graphic
section on how to set the actuating arm correctly.
Faded beam splitter mirrors seem to be very common on
Graphics of a certain age. I don't know what happens to
them. Fortunately, they are easy to replace and once done
will probably never have to be done again.
A makeshift fix is to place a neutral or colored filter
over the upper window of the RF. This will increase the
contrast of the two images although it is no substitute for
replacing the beam splitter.

There is no eyepiece on the rangfinder but most came with
a plain tube to shield image. This was not supplied on all
Graphics or it may be missing. Some RFs have coarse threads
in the eyepiece for this to thread into, some have a bracket
on the back of the camera in line with the eye window of the
RF for this tube.
There were also telescopes made to fit the Kalart. One
was made by Kalart but there were others. I've never managed
to find one. A telescope on the eye window has the effect of
having a greater base distance for the rangefinder and thus
increasing its accuracy. Back when the Contax camera came
out to compete with Leica it advertised it had a greater RF
base so was more accurate. The Leica, however, had a 2X
telescope built in so the _effective_ base of the two was
about the same.
The Kalart is very accurate when set up correctly.
Correct set up is tedious but once done will not have to be
done again unless the lens is changed.

I had problems with 'drift' in a Kalart.

I traced it to the screw that aligns the lower prism.

The screw bears against the back of the prism, which is
held against the screw tip by its springy sheet metal
mount.

In my case there was an air gap between the screw and the
prism bracket, allowing the prism mount to 'twang'.
It wasn't the twang, but the gradual shift of the prism with
temperature, storage position and phase of the moon that
kept the rangefinder from holding calibration.

Solution (probably not the best one) was to turn the
screw in 1.5 turns so the prism was pressing back
against the screw. At a guess the proper method would
be to remove the metal bracket and bend it back so it tensions
against the screw - but I was afraid I may bend some skew into
the bracket and never get anything to like up again.

After the repair, I found _all_ the alignment settings
needed tweaking.

I also had a problem with the spring that tensions the
prism assembly so that it bears against the cam. The end of
the spring had slipped from its proper position against the
back of the prism assembly. This caused the prism to not
follow the cam, leading to a lot of hair pulling as nothing
ever lined up the same way twice.

--
Nicholas O. Lindan, Cleveland, Ohio
Consulting Engineer: Electronics; Informatics; Photonics.
Remove spaces etc. to reply: n o lindan at net com dot com
psst.. want to buy an f-stop timer? nolindan.com/da/fstop/

I had problems with 'drift' in a Kalart.

I traced it to the screw that aligns the lower prism.

The screw bears against the back of the prism, which is
held against the screw tip by its springy sheet metal
mount.

In my case there was an air gap between the screw and the
prism bracket, allowing the prism mount to 'twang'.
It wasn't the twang, but the gradual shift of the prism with
temperature, storage position and phase of the moon that
kept the rangefinder from holding calibration.

Solution (probably not the best one) was to turn the
screw in 1.5 turns so the prism was pressing back
against the screw. At a guess the proper method would
be to remove the metal bracket and bend it back so it tensions
against the screw - but I was afraid I may bend some skew into
the bracket and never get anything to like up again.

After the repair, I found _all_ the alignment settings
needed tweaking.

I also had a problem with the spring that tensions the
prism assembly so that it bears against the cam. The end of
the spring had slipped from its proper position against the
back of the prism assembly. This caused the prism to not
follow the cam, leading to a lot of hair pulling as nothing
ever lined up the same way twice.

--
Nicholas O. Lindan, Cleveland, Ohio
Consulting Engineer: Electronics; Informatics; Photonics.
Remove spaces etc. to reply: n o lindan at net com dot com
psst.. want to buy an f-stop timer? nolindan.com/da/fstop/

"Nicholas O. Lindan" wrote in message
nk.net...
I had problems with 'drift' in a Kalart.

I traced it to the screw that aligns the lower prism.

The screw bears against the back of the prism, which is
held against the screw tip by its springy sheet metal
mount.

In my case there was an air gap between the screw and the
prism bracket, allowing the prism mount to 'twang'.
It wasn't the twang, but the gradual shift of the prism
with
temperature, storage position and phase of the moon that
kept the rangefinder from holding calibration.

Solution (probably not the best one) was to turn the
screw in 1.5 turns so the prism was pressing back
against the screw. At a guess the proper method would
be to remove the metal bracket and bend it back so it
tensions
against the screw - but I was afraid I may bend some skew
into
the bracket and never get anything to like up again.

After the repair, I found _all_ the alignment settings
needed tweaking.

I also had a problem with the spring that tensions the
prism assembly so that it bears against the cam. The end
of
the spring had slipped from its proper position against
the
back of the prism assembly. This caused the prism to not
follow the cam, leading to a lot of hair pulling as
nothing
ever lined up the same way twice.

--
Nicholas O. Lindan, Cleveland, Ohio
Consulting Engineer: Electronics; Informatics; Photonics.
Remove spaces etc. to reply: n o lindan at net com dot com
psst.. want to buy an f-stop timer? nolindan.com/da/fstop/

The screw that bears on the prism is the basic infinity
adjustment for the rangefinder. The spring metal bracket for
the prism should follow it right down to the boss its
threaded into. Probably the prism got bent up at some point.
The bracket and prism are held in place by two tiny screws
on the bottom of the same boss the adjustment screw is in.
Normally the screw will be about helf way so a turn and a
half is acceptable.
If you have a rangefinder where the adjustment is
questionable the way to set it is to make sure the
rangefinder actuating arm is installed correctly as I
described in my previous post. Then make sure the infinity
stops for the lens standard are set so that infinity focus
on the ground glass requires racking out the focus track
about 1/32 inch from its back stop. This should also put the
distance scale on Anniversary Graphics about in the right
place. The scale on a Pacemaker can be put anywhere so is
not useful as a guide unless you know for certain its in the
right place.
In any case, with the infinity stops in the right place,
the eccentric on the bed at center position (slot straight
up and down) the rangefinder should indicate infinity. If it
doesn't adjust the little screw until it does. The mid and
close distance adjusters should not have any effect on this
but they should be on the starting values for the particular
focal length lens given in the Kalart manual. If this set up
is done carefully sometimes the rangefinder will come right
in on the starting values. Usually it doesn't. After setting
the mid and close distances so they are correct the
rangefinder should be checked at intermediate distances.
Sometimes it will be correct at infinity, 15 feet and 4 feet
but not at 6 or 8 feet or at 30 feet. This is an indication
the infinty adjustments are off somehow. The position of the
actuating arm is critical. Some instructions say to place
the end of the arm against the back of the camera. This may
work but the correct position is the greatest rearward
position the cam on the camera bed can have when the camera
is folded. This is actually a little forward of the back of
the camera box. The eccentric should be set at its maximum
rearward adjustment and the end of the arm held against it
with a rubber band while the set screw is tightened. Then
the eccentric is moved back to its center position. This
method of adjustment gives the greatest range for the cam in
the rangefinder. Actually, this is not a single cam but a
couple of coupled cams. The slider adustments adjust where
they overlap and how much allowing the approximation of a
range of cams to cover the focal length range of the
rangefinder. If the infinity and arm settings are not right
the curvature of the cam is wrongm, or rather, you will be
working on the wrong part of the cam, so the coincidence
with the lens will never be right.
It is also important to watch for backlash when making
adjustments to the sliders. Work the focus arm back and
forth a few times after each step to make sure it really is
where you want it. The adjustment procedure is tedious as
hell but does work and when done right the RF is very
accurate down to quite close distances. It is interesting
that in the patent literature it is stated that the
rangefinder was never intended for close use. Nonetheless it
does work down to 4 feet, sometimes even down to the limit
of movement of the arm, about 3-1/2 feet for a 4x5 camera
with a 135mm lens on it.


--
---
Richard Knoppow
Los Angeles, CA, USA

"Nicholas O. Lindan" wrote in message
nk.net...
I had problems with 'drift' in a Kalart.

I traced it to the screw that aligns the lower prism.

The screw bears against the back of the prism, which is
held against the screw tip by its springy sheet metal
mount.

In my case there was an air gap between the screw and the
prism bracket, allowing the prism mount to 'twang'.
It wasn't the twang, but the gradual shift of the prism
with
temperature, storage position and phase of the moon that
kept the rangefinder from holding calibration.

Solution (probably not the best one) was to turn the
screw in 1.5 turns so the prism was pressing back
against the screw. At a guess the proper method would
be to remove the metal bracket and bend it back so it
tensions
against the screw - but I was afraid I may bend some skew
into
the bracket and never get anything to like up again.

After the repair, I found _all_ the alignment settings
needed tweaking.

I also had a problem with the spring that tensions the
prism assembly so that it bears against the cam. The end
of
the spring had slipped from its proper position against
the
back of the prism assembly. This caused the prism to not
follow the cam, leading to a lot of hair pulling as
nothing
ever lined up the same way twice.

--
Nicholas O. Lindan, Cleveland, Ohio
Consulting Engineer: Electronics; Informatics; Photonics.
Remove spaces etc. to reply: n o lindan at net com dot com
psst.. want to buy an f-stop timer? nolindan.com/da/fstop/

The screw that bears on the prism is the basic infinity
adjustment for the rangefinder. The spring metal bracket for
the prism should follow it right down to the boss its
threaded into. Probably the prism got bent up at some point.
The bracket and prism are held in place by two tiny screws
on the bottom of the same boss the adjustment screw is in.
Normally the screw will be about helf way so a turn and a
half is acceptable.
If you have a rangefinder where the adjustment is
questionable the way to set it is to make sure the
rangefinder actuating arm is installed correctly as I
described in my previous post. Then make sure the infinity
stops for the lens standard are set so that infinity focus
on the ground glass requires racking out the focus track
about 1/32 inch from its back stop. This should also put the
distance scale on Anniversary Graphics about in the right
place. The scale on a Pacemaker can be put anywhere so is
not useful as a guide unless you know for certain its in the
right place.
In any case, with the infinity stops in the right place,
the eccentric on the bed at center position (slot straight
up and down) the rangefinder should indicate infinity. If it
doesn't adjust the little screw until it does. The mid and
close distance adjusters should not have any effect on this
but they should be on the starting values for the particular
focal length lens given in the Kalart manual. If this set up
is done carefully sometimes the rangefinder will come right
in on the starting values. Usually it doesn't. After setting
the mid and close distances so they are correct the
rangefinder should be checked at intermediate distances.
Sometimes it will be correct at infinity, 15 feet and 4 feet
but not at 6 or 8 feet or at 30 feet. This is an indication
the infinty adjustments are off somehow. The position of the
actuating arm is critical. Some instructions say to place
the end of the arm against the back of the camera. This may
work but the correct position is the greatest rearward
position the cam on the camera bed can have when the camera
is folded. This is actually a little forward of the back of
the camera box. The eccentric should be set at its maximum
rearward adjustment and the end of the arm held against it
with a rubber band while the set screw is tightened. Then
the eccentric is moved back to its center position. This
method of adjustment gives the greatest range for the cam in
the rangefinder. Actually, this is not a single cam but a
couple of coupled cams. The slider adustments adjust where
they overlap and how much allowing the approximation of a
range of cams to cover the focal length range of the
rangefinder. If the infinity and arm settings are not right
the curvature of the cam is wrongm, or rather, you will be
working on the wrong part of the cam, so the coincidence
with the lens will never be right.
It is also important to watch for backlash when making
adjustments to the sliders. Work the focus arm back and
forth a few times after each step to make sure it really is
where you want it. The adjustment procedure is tedious as
hell but does work and when done right the RF is very
accurate down to quite close distances. It is interesting
that in the patent literature it is stated that the
rangefinder was never intended for close use. Nonetheless it
does work down to 4 feet, sometimes even down to the limit
of movement of the arm, about 3-1/2 feet for a 4x5 camera
with a 135mm lens on it.


--
---
Richard Knoppow
Los Angeles, CA, USA

"Nicholas O. Lindan" wrote in message
nk.net...
I had problems with 'drift' in a Kalart.

I traced it to the screw that aligns the lower prism.

The screw bears against the back of the prism, which is
held against the screw tip by its springy sheet metal
mount.

In my case there was an air gap between the screw and the
prism bracket, allowing the prism mount to 'twang'.
It wasn't the twang, but the gradual shift of the prism
with
temperature, storage position and phase of the moon that
kept the rangefinder from holding calibration.

Solution (probably not the best one) was to turn the
screw in 1.5 turns so the prism was pressing back
against the screw. At a guess the proper method would
be to remove the metal bracket and bend it back so it
tensions
against the screw - but I was afraid I may bend some skew
into
the bracket and never get anything to like up again.

After the repair, I found _all_ the alignment settings
needed tweaking.

I also had a problem with the spring that tensions the
prism assembly so that it bears against the cam. The end
of
the spring had slipped from its proper position against
the
back of the prism assembly. This caused the prism to not
follow the cam, leading to a lot of hair pulling as
nothing
ever lined up the same way twice.

--
Nicholas O. Lindan, Cleveland, Ohio
Consulting Engineer: Electronics; Informatics; Photonics.
Remove spaces etc. to reply: n o lindan at net com dot com
psst.. want to buy an f-stop timer? nolindan.com/da/fstop/

The screw that bears on the prism is the basic infinity
adjustment for the rangefinder. The spring metal bracket for
the prism should follow it right down to the boss its
threaded into. Probably the prism got bent up at some point.
The bracket and prism are held in place by two tiny screws
on the bottom of the same boss the adjustment screw is in.
Normally the screw will be about helf way so a turn and a
half is acceptable.
If you have a rangefinder where the adjustment is
questionable the way to set it is to make sure the
rangefinder actuating arm is installed correctly as I
described in my previous post. Then make sure the infinity
stops for the lens standard are set so that infinity focus
on the ground glass requires racking out the focus track
about 1/32 inch from its back stop. This should also put the
distance scale on Anniversary Graphics about in the right
place. The scale on a Pacemaker can be put anywhere so is
not useful as a guide unless you know for certain its in the
right place.
In any case, with the infinity stops in the right place,
the eccentric on the bed at center position (slot straight
up and down) the rangefinder should indicate infinity. If it
doesn't adjust the little screw until it does. The mid and
close distance adjusters should not have any effect on this
but they should be on the starting values for the particular
focal length lens given in the Kalart manual. If this set up
is done carefully sometimes the rangefinder will come right
in on the starting values. Usually it doesn't. After setting
the mid and close distances so they are correct the
rangefinder should be checked at intermediate distances.
Sometimes it will be correct at infinity, 15 feet and 4 feet
but not at 6 or 8 feet or at 30 feet. This is an indication
the infinty adjustments are off somehow. The position of the
actuating arm is critical. Some instructions say to place
the end of the arm against the back of the camera. This may
work but the correct position is the greatest rearward
position the cam on the camera bed can have when the camera
is folded. This is actually a little forward of the back of
the camera box. The eccentric should be set at its maximum
rearward adjustment and the end of the arm held against it
with a rubber band while the set screw is tightened. Then
the eccentric is moved back to its center position. This
method of adjustment gives the greatest range for the cam in
the rangefinder. Actually, this is not a single cam but a
couple of coupled cams. The slider adustments adjust where
they overlap and how much allowing the approximation of a
range of cams to cover the focal length range of the
rangefinder. If the infinity and arm settings are not right
the curvature of the cam is wrongm, or rather, you will be
working on the wrong part of the cam, so the coincidence
with the lens will never be right.
It is also important to watch for backlash when making
adjustments to the sliders. Work the focus arm back and
forth a few times after each step to make sure it really is
where you want it. The adjustment procedure is tedious as
hell but does work and when done right the RF is very
accurate down to quite close distances. It is interesting
that in the patent literature it is stated that the
rangefinder was never intended for close use. Nonetheless it
does work down to 4 feet, sometimes even down to the limit
of movement of the arm, about 3-1/2 feet for a 4x5 camera
with a 135mm lens on it.


--
---
Richard Knoppow
Los Angeles, CA, USA