scheimpflug -> little help?
I have been restling the scheimpflug principle for a few occasions now, and I do get the idea, but cannot seem to find any links that show some 'real-life' examples instead of the mathematical drawings.
What I am trying to do is photographing a room, and have the chair that in the front of the room and the table that's in the back to be sharp both. That should be possible, right?!
but if I focus on the chair, tilt my lens untill the table is sharp than the chair is not any longer.
what's is going on? Don't need full explaination, I am willing to think for myself, but some help would be appreciated!!
thanks a lot, kind regards game
I think you may want to tilt less and stop the lens down more. Too much tilt will only result in selective focus issues as far as I know. When you stop the lens down you most likely won't be able to tell that both are in focus through the ground glass because it will be too dark to see. Focus on one of the object and then stop down to about f45, this may achieve the results you are looking to get.
Lens board vertical - plane of focus vertical. Tilt the lens board - the plane of focus becomes slanted away from the camera.
Tilting the lens works great for flat subjects like table tops or flat desert areas, but stick something tall like a tree or chair in the frame and it goes out of focus. When you tilt the lens and use a small aperture, think of the plane of focus as a wedge, with the pointy end at the camera...this means your chair might still be out of focus no matter how small an aperture you use.
Note to self: Turn your negatives into positives.
What kind of camera are you using? If it has an on-axis tilt, it will maintain focus (at the center of the screen) when you tilt the front, otherwise you will need to re-focus. What lens are you using? With any tilt movement, there is a point where you run out of lens coverage, with a wide-angle lens you reach this point fairly soon. However, assuming the chair is not too close (say, not closer than 1.5 meters), it should be possible to get deep focus from the front to the back.
I played around with my Sinar yesterday with some extreme tilt on front and back. I managed to get our kitchen faucet, some flowers and part of the roof next door only slightly above the faucet in focus. I was a bit surpriced how much it took.
I tilt the front at the same time I do the focus back and forth, back and forth, until I find the right angle and point of focus.
Somebody may know the easier way so Im all ears/eyes
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In my early days of view camera use, I remember I fumbled around until the picture on the ground glass looked alright, often using too much tilt, and without a real clou of how exactly the plane of sharp focus is placed, and what can be and cannot be done by stopping down. Then I got Harold Merklinger's "Focussing the view camera". Not an easy read for me, but I found it extremely helpful. Since then I have a much more systematic grasp on focussing, know what to expect, and focuss in much shorter time.
He explains what he calls the "hinge rule", a crucial elaboration on the scheimpflug rule.
Harold Merklinger's book is available for download from HERE. That, and the rest of the "stuff" on that address is recommended reading.
Next, remember that you can only get one plane in focus, but you can put that just about wherever you want.
And then it depends on where the tilt axis is compared to the rear(?) node of the lens you are using. Unless the tilt axis passes directly through the node, you will get focus shift and will need to apply tilt, refocus, tilt, refocus repeatedly until you get it right. Even cameras with axis tilt may need this "fine tuning" of focus, since the lens node may not be exactly on the axis. A very few cameras have adjustable offsets, but even if mine is one of them I rarely bother to "pre-tune" the tilt axis.
-- Ole Tjugen, Luddite Elitist
Remembering that all you can do is shift where the plane is critical focus is, do this:
Originally Posted by game
1) Determine two points (nearest and farthest) with which you want your plane of critical focus to intersect.
2) Focus on the far point. Lock down the focus.
3) Tilt the standard (front one for less distortion, rear one if you want near objects to loom larger) until the near point is in focus. Don't worry about the far one going out of focus (yet). Lock down the standard.
4) Refocus on the far point. Lock it down.
5) Repeat steps 2 through 4 until both points of your plane are in focus with the lens wide open.
6) Stop down the lens until the depth of field brings everything around the plane of critical focus into acceptable focus.
Doing it this way allows you to quickly get everything in focus without having to imagine the Schiempflug line. A good mnemonic for remembering which way to tilt a standard is this: "the front faces, the back backs away". In other words, in your case you would tilt the front standard toward the plane you want (forward) to "face it" and tilt the rear one toward yourself to "back it away". I never think about where the Schiempflug line is anymore.
Remember, this won't get you any more depth of field. It just changes the position of the line around which the depth of field wraps. Hope this helps.
Start with: "focus on the near, tilt towards the far" - refocus if necessary and correct linear distortion w/rear standard) - then stop down. That's about as simple as I can say it for starting out. Some people do it the other way around, so I don't believe there's any golden rule.
"Pictures are not incidental frills to a text; they are essences of our distinctive way of knowing." Stephen J. Gould
It's hard to give advice on this scene without seeing what it looks like. Without using the camera, do you see all the things that you want in focus falling in approximately the same plane? If not, then tilting may not be the right approach.
Generally, if you have a relatively tall vertical object in the foreground (relative to whatever is in the background), this is when it's better to stop down for DOF rather than using tilt to manipulate the plane of focus. If the plane of focus is passing through the tall vertical object, then it won't be in focus.