Base Tilt Advantages?

[jmolligo]

Although I have been using Large Format equipment for quite some time (about 10 years) I have never fully understood the advantages of Base Tilts (as opposed to Axial or Assymetrical) on the front or rear - other than to prevent Yaw or mechanical obstruction of the standards by the camera.

So, as I'm fortunate enough to have all your knowledge at my disposal, I thought I'd ask.

Are there any other advantages to the Base Tilt (other than preventing Yaw)?

[Ian Grant]

Base tilt has no advantages for image making over Axial tilts, it's just a lot cheaper to make cameras that way.

Ian

[Vaughn]

My guesses...simplifies camera design and at the same time provides stability.

Vaughn

[edtbjon]

I don't think that it's easier to design or make a camera with base tilt as compared to axial tilt. But I fully agree that it makes the camera somewhat more stable. Also, don't deminish the prevention of yaw. When a shot becomes complicated with both front and back tilts and swings, the presence of yaw can make the shot unmanagable. The intention with tilts and swings is IMO first to get everything sharp without having to resort to f/90 or so. It's equally important to also manage perspective while doing this. If the camera is not designed to prevent yaw from appearing, it's easy to get lost which results in lost quality, i.e. using smaller aperture openings than needed. This results in need for more light (maybe 4 times the flash output in a studio or several seconds exposure instead of one) and refraction effects on the film etc.
I think Sinar was the forerunner of building yaw-free cameras and their articles and camera manuals describes the problems and solutions quite well, using mock-ups with cameras and different scenes. Of course they promotes their own products, but without a lot of hype. They compare "before and after" with the Norma and the F/P series cameras, all cameras with very good reputation. I have tried to read other articles on Sheimpflug etc. but they are all very technical/theoretical and very easy to put aside.

//Björn

[philsweeney]

Personally I find a front standard without center tilt a major hinderance. Having a yaw-free camera is not that important for my work either. Though I do own a Sinar F1. From a the book "Basics and Applications" by Urs Tillmanns he advises "Certain designs with centre tilt may result in problems in film loading at extreme movements in the horizontal format." That book is geared towards using Sinar cameras.

[Nicholas Lindan]

... don't deminish the prevention of yaw...

Yaw prevention is due to the order of the tilt and swing mechanisms.

In a Sinar design the standard first tilts and then swings perpendicular to the lens axis - the swing axis doesn't stay with the camera rail.

A conventional camera has the swing mechanism first and the tilt second. When swinging a tilted standard the standard gyrates around the swing axis, which is always perpendicular to the rail.

Sinar P's have asymmetric axis tilts (the tilt axis is a few cm lower than the lens) - the mechanism has the advantage of focus first, tilt second. The tilt and focus don't interact. The F series has real base tilt with the disadvantage that tiliting and focusing are a back and forth affair; this disadvantage is also present in true axis tilts but is somewhat minimized and much easier to deal with.

Given my druthers on the F I would rather forgo the yaw feature for asymmetric axis tilt. Base tilt is a real PITA. I rarely twist an F into a pretzel for product table-top pictures.

[Nicholas Lindan]

Urs Tillmanns ... advises "Certain designs with centre tilt may result in problems in film loading at extreme movements in the horizontal format."

That is the reason professional center tilt cameras have 'L' standards.

[David A. Goldfarb]

For field cameras (both flatbed and monorail), rear base tilt makes the camera lighter and more compact than it would be if it had rear axial tilt, because you can eliminate the uprights and knobs required for rear axial tilt.

[Ian Grant]

Some field / commercial cameras have axial tilts, the Agfa Ansco's allowed a small amount of rear axial tilt, and a lot more front axial tilt. This makes the camera much faster to use.

Ian

[jmolligo]

Thanks for all the in depth thought on this. I appreciate all the responses.