Questions on Scheimpflug principle

[sweat100]

I would like to clarify some questions based on this principle. I read about the Scheimpflug line and the hing line. What was said that all the 3 planes intersect to form a line giving you sharp focus. I do not get what they mean by a wedge shape DOF.
Do they mean the plane of focus is now tilted? Thus am i right to say for example object in the front say (10cm from the lens) of height of 1cm is focused, then some distance further away (50cm from the lens), the object at height of is 5cm is focused? But if lets say I have another object at 50cm away from the lens, but height is 1 cm, it wont be focused?

By stopping down the aperture when using the Scheimpflug principle, the DoF now is like an angle that spans from the focus plane?

What is a good way that you use this principle while in the field? Any quick and fast method? I tried to use it, it works but, focusing really takes some time as you need to tilt and readjust for a few times to get it right.

 

[fuwen]

Oh yes, I would like to know the answer also. I have difficulties get the principle working properly with my SL66.

 

[sabrewolf]

yes, the plane of focus is now tilted and no longer parallel to the film. As a result DOF also no longer parallel to the film, instead it will be shaped like a wedge, smaller near the photographer and getting wider at infinity (the plane of focus will still be in the middle of the DOF).


Using this method, you can get a huge DOF to infinity at full lens aperture, or the other way round, an extremely shallow DOF. Of course Large Format benefit more for this because large format lens sometimes need aperture as small as F56 (not 5.6) for huge DOF, even in daylight that will be problematic.

More readings: http://en.wikipedia.org/wiki/Scheimpflug

 

[theRBK]

Here's an article on the Scheimpflug principle, with a picture at the top which clearly illustrates the effect as well as the wedge shaped area of reasonably sharp focus...

http://www.luminous-landscape.com/tutorials/focusing-ts.shtml

 

[Leong23]

Hi

Just happen to saw this thread on Scheimpflug principle.

Just sharing this 2 photos taken using shifting method to increase DOF for tilted subject.

Both are taken using DSLR with Nikon 85mm PC Lens, not Medium format, please tell me if you guys want me to remove it.

 

[boochap]

Hi

Just happen to saw this thread on Scheimpflug principle.

Just sharing this 2 photos taken using shifting method to increase DOF for tilted subject.

Both are taken using DSLR with Nikon 85mm PC Lens, not Medium format, please tell me if you guys want me to remove it.

leave it here.. these pix will explain why so many film lovers are still hanging on with films. :bigeyes:

 

[ST1100]

leave it here.. these pix will explain why so many film lovers are still hanging on with films.

He mentioned the pictures were done on DSLR... why the sudden reference to film?

 

[boochap]

He mentioned the pictures were done on DSLR... why the sudden reference to film?

so that most film lovers here know exactly what they are getting out of the photographic films.. when they start to compare their shots vs that dslr dragonfly pix..

 

[boochap]

sorry. i shouldn't OT.

i also do Scheimpflug with 4x5.
simply visually align film plane to be parallel with object plane.
at this point, everything falling on the object plane will be focus sharp. then step down or up to adjust your DOF.

 

[sweat100]

Hi Leong23, from the 2nd shot, it seems that the object is in a flat plane. I am not very sure how did you applied Scheimpflug technique.

 

[sweat100]

sorry. i shouldn't OT.

i also do Scheimpflug with 4x5.
simply visually align film plane to be parallel with object plane.
at this point, everything falling on the object plane will be focus sharp. then step down or up to adjust your DOF.

Hi boochap, from the links I read in this thread, I think to apply the principle, your film should not parallel with the object plane. What you have mentioned should be more on perspective correction.

 

[Leong23]

Hi Leong23, from the 2nd shot, it seems that the object is in a flat plane. I am not very sure how did you applied Scheimpflug technique.

If taken a closer look at the head of the damselfly, you will notice that the subject is slightly tilted.

Example of a similar shot that show how a damselfly look like in flat plane.

Although some might said that it is not neccessary to apply scheimpflug technique as stepping down might also able get head to tail sharpness. But most of the time stepping down is not preferable as it might not get head to tail sharpness due to high magnification and it will also loses the clean background.

 

[Leong23]

Hi boochap, from the links I read in this thread, I think to apply the principle, your film should not parallel with the object plane. What you have mentioned should be more on perspective correction.

Yap, the film or sensor plane should not be parrallel to the object plane if you using Scheimpflug principle.

 

[boochap]

Hi boochap, from the links I read in this thread, I think to apply the principle, your film should not parallel with the object plane. What you have mentioned should be more on perspective correction.

Oooppss. yaya. see, my LF theory rusty liao.