PC 19mm f/4 E ED

[PedroS]

Ai, ai... you are not helping the cause... 

[Erik Lund]

Thanks the images are quite crisp! Very nice.

What Sony is this?

[Royal Winchester]

They may not be pretty, but here are some full frame shots.
Another nice thing, you can focus beyond infinity to give you control of tilted plane of focus beyond aligned with lens axis.

https://www.flickr.com/photos/144986562@N07/albums/72157675054003430

[Bjørn Rørslett]

...
Another nice thing, you can focus beyond infinity to give you control of tilted plane of focus beyond aligned with lens axis.
...

That only implies the Scheimpflug principle is violated.

[Royal Winchester]

I don't think so...
The hinge point remains the same, but the plane of tilt goes past horizontal.  At infinity focus, the Sheimpflug point and the hinge point are equidistant from the camera, giving the axis-aligned plane.  Past infinity the scheimpflug point is slightly nearer the camera than the hinge point giving a tilted plane, just tilted in the opposite direction than for nearer than infinity focus.

[Bjørn Rørslett]

You are probably overdoing the tilt or moving the camera too low, both situations will cause violations of the Scheimpflug set up and cause trouble getting distant objects into focus along their entire vertical dimension. Typically one sees the tree tops or mountain peaks in sharp focus and their base is off.

A familiar situation for view camera users until one realises what movements can or cannot do. Been there myself.

[Royal Winchester]

Yes!  That is exactly the common scenario.  Regardless of the degree of tilt, at infinity focus the plane of focus will be parallel to the optical axis.  With longer focal lengths, that plane is displaced further away.  J=f / sin theta.
With a longer focal length TS lens, for example, the 85mm, this means that even fully tilted there can be quite a few near objects at the edge of the frame which are out of focus.  To bring them in focus, the photographer will use the focus ring and bring the focus closer, which tilts the plane of focus up (if the lens is tilted down) but it still passes through the hinge point.  Hence, when the near objects are in focus the tilted plane now puts the mountain tops in focus and not their bases because of the upward tilted focus plane.  What is so delightful with the 19mm is that not only is the focus plane much less displaced (lower f means lower J), but the increased field of view means this focus plane intersects the view frustrum much closer to the camera making it far, far easier to have near and distant objects in focus within the frame.  It truly allows images that just aren't possible without these movements!

[Bjørn Rørslett]

Almost needless to say, making such use of a very wide angle tilt/shift lens really necessitates a camera with excellent LiveView performance. For example, I wouldn't trust my D800 to take on such a challenge.

[Royal Winchester]

That matches my experience.  Live view, and in particular focus peaking, really help visualize these effects.

As I'm certain most of us on here do, if Bjorn R. says something that conflicts with what you think you know, you should immediately
double check your ideas, because chances are it is you, and not Bjorn, who is mistaken.

In order to test what I thought I knew about the focus plane I set up a ruler against the wall, and made a mark near the camera, 12 inches up the wall, perhaps 15 feet from the ruler.
Carefully set up and leveled my camera with the 19mm on it.
I measured the height of the camera from the floor, and then used tilt and focus to get the mark and the 12 inch point in focus.
The camera was 23-24 inches high (best estimate of the center of the sensor plane) so with the formula J=f/ sin theta 23-24 inches is 11-12 inches above the 12 inch mark and theta should be 3.6-3.9 degrees and focus should be infinity.
It was just under the 4 degree mark and at infinity.
The I focused further, and you can see the focus plane down the right wall.  Now the camera is still level, with the same lens tilt, but by focusing beyond infinity I now have the downward tilted focus plane.

Whew!  This is exactly as I would expect and as described by the Sheimplug principle.

I'm going to have a lot of fun with this lens.  Going to Florida for Thanksgiving, should be some long flat beach vistas to photograph!

-Royal

[Royal Winchester]

I'll also point out that, despite all the fancy coatings, there are some situations in which you get quite a bit of flare...

[Erik Lund]

Almost needless to say, making such use of a very wide angle tilt/shift lens really necessitates a camera with excellent LiveView performance. For example, I wouldn't trust my D800 to take on such a challenge.

This is a big consideration of mine, although the D810 has quite good Live View it will still require a lot of rear screen pixel peeping to nail both focus, tilt and shift movements and a tripod,,,

[Ilkka Nissilä]

This is a big consideration of mine, although the D810 has quite good Live View it will still require a lot of rear screen pixel peeping to nail both focus, tilt and shift movements and a tripod,,,

For the first three years I was trying to use tilt in landscapes and close-ups, I had rather poor rate of technical success, but eventually I figured out how to do it so that I get consistent results on a routine basis.

This might not work for someone else but here is my procedure for adjusting tilt. I first frame the shot normally and focus on the main area of interest in the image. Then, using the optical viewfinder, I simultaneously adjust tilt and focus to get them as precisely correct as I can within the limitations of my eyesight and the viewfinder. After this I turn on live view, open up the aperture and refine focus on the main subject.  Then I stop down the lens to shooting aperture (my preferred landscape aperture is around f/9, but if the subject deviates from a plane by a lot, then I may stop down further to f/11 or even deeper).  I take a shot. Then I evaluate the result and see if it acceptable across the image area. Usually it is but sometimes there is an area which is still not sharp enough. I may then redo the procedure trying to get it more precisely correct. If the dual area split live view view on the D810 is applicable to setting tilt and focus, I use that. Basically this is applicable in situations where I'm doing a near-to-far landscape as a vertical composition. 

Zooming in the live view image and scrolling around by itself doesn't work for me for adjusting tilt as I need to see the effects on the whole image at the same time. With the OVF I can get the focus and tilt close enough so that I can just refine the focus at one point using LV and the error in the tilt is so small that I can usually ignore it.

There are shortcomings to PC lenses - lower contrast, some propensity to flare etc. compared to regular non-tilt-shift lenses, and this might be more severe on the 19mm due to the lack of possibility to use a hood. Using your hand or some black object as a flag to block unwanted point light source from hitting the front element of the lens may work at times if the light source is just outside of the image area.

Thanks for everyone who posted images.

[Thomas Stellwag]

Ilkka, thx - will try your roadbook next time

[Erik Lund]

Thank You Illka, you confirm my concerns!

[Bjørn Rørslett]

In the old times of film I used view cameras and a 10X loupe to study the groundglass thoroughly when setting up the camera for any shot requiring tilt and/or shift. Making focusing errors on 4x5" sheet film is not something you would like to develop as a habit, I can assure.