Comments on the Sinar P?

[Theodoros]

Theodoros - "yaw free" is irrelevant in most architectural work because the camera is typically leveled first, before tilts, swings, or rise. It's logical application is production tabletop studio photography. I'll let you and Bob argue the finer points of the subject. Sinar made a big fuss about buying perfectly nodal-centered mounted lenses from them, at a premium of course. Symmetrical, assymetrical, whatever; I just do it based on rote familiarity with each particular style of camera, having forgotten the theory long ago. But to suggest that there is anything less precise about outdoor photography is utter ballyhoo. And there is certainly
more demand on equipment reliability. Try getting a little sand in that P gearing.

I think you underestimate yaw free operation importance for architectural photography... Other than yaw free being the only way for the photographer to have completely distortionless architectural images, it also allows stitching by rotating the camera around the nodal point (same as the entrance pupil) axis and thus achieve extreme WA completely distortionless shots.... Further more, one can use swings for half the angle between shots of the plane he is after to stitch, thus achieving a previously unimaginable perspective...

Sinar's customer's service of offering correct positioning for each different lens for yaw free operation, should have been followed by other makers too, but... wouldn't it be far better if makers would make the frames able to be adjusted back and forth on their respective standards so that the user is forced to get more self involved as to have his camera to operate correctly?

Heck, 90% of the cameras out there have design flaws like if they have been designed by ignorants and the few that are designed "by the book" fail to finish the job when it comes to mount the lens (or the image area) at the right position...

EDIT: And then you get salesmen in forums trying to call "night for being a day"...

[Drew Wiley]

Many architectural photographer rely on very wide angle lenses which stretch and distort the image regardless. Guess someone could stitch if they had nothing
better to do with their time, or they had total control of the lighting the whole session. I thought stitching was for people who couldn't afford new sox. But if you'll excuse that quip, find me a interesting structure that is actually square to begin with! I even sell special instruments to contractors for calculating certain corrections based on the premise that no room is actually square! And lots of structures are not truly level either. But yeah, all machinery is some kind of compromise between price and performance, even the lenses we use. Maybe if you're NASA or the DEA you can afford something significantly better. But that fact doesn't stop me from enjoying my various Sinar cameras. They get the job done.

[Theodoros]

.............find me a interesting structure that is actually square to begin with!

Try shooting the full width of a temple in an 11th century ancient byzantine monastery!

EDIT: square is irrelevant to distortionless

[Drew Wiley]

It would be a treat to me just to visit and see such a thing.

[Bob Salomon]

Gosh Bob! You can't patent YAW FREE operation of a camera because no camera by itself can ensure that the result will be yaw free... YAW FREE is a lens positioning matter with respect to the image area, a camera will work different with different lenses depending on each individual lens entrance pupil position...

Most makers of cameras claim "yaw free" operation these days... and guess what... All of them "forget" to add the phrase: "only with symmetrical lenses", All of them "forget" to mention that the tilt plain and swing plane must cross on the axis that also crosses the entrance pupil of the lens and 90% of the makers (Linhof included - Sinar excluded on the 90%) forget to mention that if your side shift mechanism is above your swing or the up-down shift above your tilt and you combine the movements... you can "kiss yaw free operation goodbye" even if the entrance pupil is positioned correctly... give us a brake will you? ...and please stop posting nonsense like cameras becoming "yaw free" if their swing is above tilt or "all cameras becoming yaw free if they are turned 90 degrees to the side" (especially since you never have backed up with some theory as to support those nonsense)....

We are not all as ignorants as some of your customers might have been in the past as to invent sale properties of cameras that do not exist...

Can't you read? I said that the patent was not for yaw free.

Read first. Then learn photographic terminology. Then study what different cameras can do and then comment.

[Theodoros]

Can't you read? I said that the patent was not for yaw free.

Read first. Then learn photographic terminology. Then study what different cameras can do and then comment.

Ohhhh no... not again! Bob why was the Kardan the first yaw free camera? Can you please explain (for once) what makes it yaw free? Please explain the fundamentals behind yaw free operation as I have and state where you disagree and why... Please avoid bold statements like "all cameras are yaw free if turned by 90 degrees" or "cameras are yaw free if the swing is above tilt" this time, or back up your statements with some (sensible) reasoning...

As far as I know... no camera that is first focused accurately and then needs refocusing after movements are applied is yaw free... the more the focus is lost, the more the yaw error that has been induced... do you disagree with that?

[Bob Salomon]

Ohhhh no... not again! Bob why was the Kardan the first yaw free camera? Can you please explain (for once) what makes it yaw free? Please explain the fundamentals behind yaw free operation as I have and state where you disagree and why... Please avoid bold statements like "all cameras are yaw free if turned by 90 degrees" or "cameras are yaw free if the swing is above tilt" this time, or back up your statements with some (sensible) reasoning...

As far as I know... no camera that is first focused accurately and then needs refocusing after movements are applied is yaw free... the more the focus is lost, the more the yaw error that has been induced... do you disagree with that?

This has been posted several times and there is an article on it in the Linhof Camera Story book.
The first Kardan shown had a knuckle type joint ( the origin of the Kardan name) that did tilts and swings at the same point and was hence yaw free.
However Linhof decided that this joint was too complicated so the production models were optical axis movement cameras and were not yaw free.

Later Linhof models like the Kardan Master L, TL, GTL, GT, etc. did have dual tilt movements, like the Sinar P, one below the swing point to level the standard when the camera was inclined, and one above the swing point for performing Scheimpflug maneuvers. Many other cameras from other manufacturers also had this setup.
Since, as stated earlier, any yaw prone camera is yaw free when swung 90° to make the normal swing point become the tilt point Linhof added an extra bubble level to the TechniKardan as it was very easy to swing this camera over on a proper head and then use it as a yaw free camera. Apparently not many users did this.

Linhof, and other view camera manufacturers regularly supplied lenses factory mounted on the boards, if you were willing to pay the extra price that the factories, including Sinar, charged for the lens. If not, Linhof supplies boards with pre milled, properly centered holes for each shutter size as well as boards with pre bored pilot holes for those who want to bore their own holes. The price for the boards, with pilot hole or sized hole, are the same.

[Theodoros]

This has been posted several times and there is an article on it in the Linhof Camera Story book.
The first Kardan shown had a knuckle type joint ( the origin of the Kardan name) that did tilts and swings at the same point and was hence yaw free.
However Linhof decided that this joint was too complicated so the production models were optical axis movement cameras and were not yaw free.

Later Linhof models like the Kardan Master L, TL, GTL, GT, etc. did have dual tilt movements, like the Sinar P, one below the swing point to level the standard when the camera was inclined, and one above the swing point for performing Scheimpflug maneuvers. Many other cameras from other manufacturers also had this setup.
Since, as stated earlier, any yaw prone camera is yaw free when swung 90° to make the normal swing point become the tilt point Linhof added an extra bubble level to the TechniKardan as it was very easy to swing this camera over on a proper head and then use it as a yaw free camera. Apparently not many users did this.

Linhof, and other view camera manufacturers regularly supplied lenses factory mounted on the boards, if you were willing to pay the extra price that the factories, including Sinar, charged for the lens. If not, Linhof supplies boards with pre milled, properly centered holes for each shutter size as well as boards with pre bored pilot holes for those who want to bore their own holes. The price for the boards, with pilot hole or sized hole, are the same.

More bold statements still... can you please at least answer me if you agree that if a camera is focused (no movements applied) and after movements are applied, focus is lost... does this mean that the camera is yaw prone? Do you agree on this?

EDIT: And that the more yaw prone the camera, the more focus is off?

EDIT 2: Let me give you a hint... the answer is yes! Focus will be off only if the camera (rather the system) is yaw prone...

Then next question should be.... "why focus has been lost if only a tilt movement has been applied"?

Hint-2... Because the distance of the entrance pupil of the lens to the image area has changed?

[Bob Salomon]

More bold statements still... can you please at least answer me if you agree that if a camera is focused (no movements applied) and after movements are applied, focus is lost... does this mean that the camera is yaw prone? Do you agree on this?

EDIT: And that the more yaw prone the camera, the more focus is off?

No, that happens with any base tilt camera and has nothing to do with the subject yawing on the ground glass which is what will happen with any yaw prone camera if a tilt and swing are used at the same time.

Here is some reading for you to help you learn what yaw means in a view camera.

http://www.sinar.ch/en/yaw-free/

[Theodoros]

why do I suspect that Bob won't be answering any of the above... Nevermind, I may as well ask him some more questions which should follow the above...

If the swing point is on the same axis as the tilt point and the lens loses its focus when tilted, is there any possible chance it won't lose focus by exactly the same amount if one swings it for the same angle that he tilted it before?

HINT: The answer is NO-absolutely not! ...focus will be off exactly by the same amount...

Then... if you turn the camera by 90 degs and you swing the lens (so that you now make it tilt) will that make any difference to the focusing?

HINT: The answer is "don't make me laugh"....

Next Q: Then why you insist posting false information like that or all the rest of nonsense bold statements that you have all this time Bob?