Sinar Yaw-free Axis and Asymmetric tilt - trying to work out the benefits

[nick mulder]

When it comes to view cameras I've only ever used a Sinar P so I have nothing to compare it to.

I've read up about the yaw free axis design and can see how it is useful but what still has me puzzled is how the asymmetric tilts are helpful.

Don’t get me wrong, I love my Sinars and cant fault them when using them, its just on the face of it it seems that a centred tilt axis would be more logical - the choice of an off axis tilt centre seems at least arbitrary, why not be asymmetric about the other side of the image for instance ?

Clearly I'm missing some conceptual point here and it's probably fair to say that using a normal view camera would outline the benefits, but experience has told me that at least here in NZ, my own Sinars are the only view cameras I'm going to chance upon for some time...

What got me thinking about this is that I am building a 11x14 back for my Sinar P 8x10 standard, because of this the tilt axes are going to change - I can move the mount left and right to change the vertical axis tilt point but for the horizontal axis there is nothing I can really do about it (except make it even worse by extending the mount and making the tilt axis not even on the image itself ) .

Come to think of it, when changing from portrait to landscape with a standard 8x10 back there would be a change in the centre of axis ...

Something to ponder

Any illumination appreciated,
thanks
Nick

 

[David A. Goldfarb]

The attraction of the asymmetric tilt and swing on the Sinar is that on the rear standard, you can see the focus effects of the movements on the groundglass without refocusing, because the swing and tilt axes intersect the film plane represented on the ground side of the glass. If you want to apply the movements to the front standard, you just read the angle off the scale on the rear standard and apply the corresponding movement to the front standard, and then return the rear standard to zero.

So say you want to tilt. You focus on the area of the scene intersecting the dotted line on the bottom of the groundglass, then tilt until the rest of the desired focal plane is in focus on the groundglass, and there you have your tilt angle, without any need for iterative focus and tilt. If you want the movement on the front standard, just read the tilt angle off the rear standard, apply corresponding tilt to the front standard, set the rear tilt back to zero, fine tune the focus, and you should be in focus without further tilt adjustment.

What happens if there is nothing interesting to focus on where the dotted line is? Use rear rise/fall to move the dotted line to a more useful location, find the tilt angle as described above, and then return the rise/fall to the original position to restore the original composition. The Linhof Master GTL addresses this problem by making it possible to move the tilt and swing axes anywhere on the groundglass.

 

[nick mulder]

golly gosh and popcorn - really ?!

cool...

I never had a manual - only just discovered what the DOF thingy hoohah on the wotnot thingy did a few weeks ago

Any manual .pdf's about ? (aside from those already linked)

 

[Sparky]

That's really funny, David - I had no idea you could do that on a GTL.. you mean all that extra 100lb of metal actually has a purpose...?? Crazy.

But yeah - I side with david and I'll further add the summary that there is precious little difference between a centre and an asymmetric tilt, practically speaking. In both cases you have a guide axis that one focuses on before tilting. (reminds me: I haven't tilted in a LONG time..!! Gotta put that on my to-do list!!)

As for the 8x10 back portrait vs landscape thing. Your tilt location should not change at all. As far as distance from the centre axis of the film goes... the location is determined ONLY by vertical pivot location and offset of film plane from plane formed by centre of pivot... if that makes any sense at all...!

 

[nick mulder]

ah, yes ...

okidoki I get it

I am simplifying my homemade 11x14 (for weight and size reasons and the fact I am yet to shoot in landscape after maybe 2 years) into a portrait only verison, I thought maybe I could simply turn the frame I build around (a rectangle) and mount it again in landscape if I wished in the future and hence I thought it an issue, but its not - the Sinar 8x10 back is a square !

Boy oh boy am I not looking forward to building a rectangle to square profile bellows

 

[Sparky]

maybe you don't have to. Maybe you can just build a little extender box to fit the larger format just to get you down to the point (a few inches from the back) where the regular 8x10 bellows start... just a thought...

 

[nick mulder]

I'm going to build a bellows that goes from the 11x14 back connecting to the Sinar 8x10 frame but on a 4x5 standard - the 8x10 standard now holding the 11x14 back ...

I've made one tapered bellows (square) previously and I suppose yeh I enjoy the challenge, but I know there are some painful parts involved like completing it - all the ribs nice in snug in place and a clean overlap especially whilst the glue is drying and getting all over the show.

 

[Sparky]

Well - you're more of a masochist than I am...!

 

[Frank Szabo]

When it comes to view cameras I've only ever used a Sinar P so I have nothing to compare it to.

I've read up about the yaw free axis design and can see how it is useful but what still has me puzzled is how the asymmetric tilts are helpful.

Don’t get me wrong, I love my Sinars and cant fault them when using them, its just on the face of it it seems that a centred tilt axis would be more logical - the choice of an off axis tilt centre seems at least arbitrary, why not be asymmetric about the other side of the image for instance ?

Clearly I'm missing some conceptual point here and it's probably fair to say that using a normal view camera would outline the benefits, but experience has told me that at least here in NZ, my own Sinars are the only view cameras I'm going to chance upon for some time...

What got me thinking about this is that I am building a 11x14 back for my Sinar P 8x10 standard, because of this the tilt axes are going to change - I can move the mount left and right to change the vertical axis tilt point but for the horizontal axis there is nothing I can really do about it (except make it even worse by extending the mount and making the tilt axis not even on the image itself ) .

Come to think of it, when changing from portrait to landscape with a standard 8x10 back there would be a change in the centre of axis ...

Something to ponder

Any illumination appreciated,
thanks
Nick

You said it yourself, Nick - until you've fought with a standard view camera for a few years, appreciating the Sinar (PX) is rather difficult, as they are a major pain in the posterior with no fast way to do anything. The exception here being the "F" models. They're only good for additional "P" model parts and with their base tilts are (IMHO) hardly worth the effort to drop in the trash regardless of their cost.

I've had Cambos, Toyos, old wooden Kodaks and my "P" model. I don't want to go back.

 

[nick mulder]

You said it yourself, Nick - until you've fought with a standard view camera for a few years, appreciating the Sinar (PX) is rather difficult, as they are a major pain in the posterior with no fast way to do anything. The exception here being the "F" models. They're only good for additional "P" model parts and with their base tilts are (IMHO) hardly worth the effort to drop in the trash regardless of their cost.

I've had Cambos, Toyos, old wooden Kodaks and my "P" model. I don't want to go back.

I have an F standard that was part of a package and also a beaten up norma front that my flatmate found in her car (weird gravity between me and large format).

So now I have 4 light tight 4x5 bellows to go along with my 8x10 bellows - currently using the norma and F standards as intermediary supports for some loooong extension macro work - two tripods holding up about 2 metres of rail.

Anyhoos so with the 8x10 bellows at full (some sections no longer folded) extension I can get complete coverage at f90 - larger stops get partially obscured, but the edges I'm blowing way over into complete white anyway (heavily backlit lightbox) so larger stops are still an option...

Feel free to drop your junk at my place !

 

[2F/2F]

"They're only good for additional "P" model parts and with their base tilts are (IMHO) hardly worth the effort to drop in the trash regardless of their cost."

This is laughable.