hinge and tilt angle

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Hi, I wonder if there are equations to calculate the hinge and tilt angles for a simultaneous tilt and swing. I refer to Harold M. Merklinger´s theories on the subject. Thank You, Martti

-- martti lappalainen (martti@stockholm.mail.telia.com), October 23, 2001


The proper place for Merklinger's theories and equations is the trash can. He manages to make confusing some very straight forward determinations.

-- Ellis Vener Photography (ellis@ellisvener.com), October 23, 2001.

Hey Ellis, I guess like me you did not understand a darn thing he was talking about..lol. Well I don't mean not understand, but after I went through his book, If I was to do all those calculation it would take me 2 hours to focus my camera.....lol.

-- Jorge Gasteazoro (jorgegm@worldnet.att.net), October 23, 2001.

Well said Ellis ! Months before I ordered my LF camera I thought to find what I could about LF focusing techniques, and came across the usual suspects - Adams’ “ The Camera”, Strobels’ “ View Camera Technique”, and of course the ever-confusing Mr. Merklinger. I actually deferred my purchase because of his writings. He has some QuickTime movies on his web site which are useful, but his writings would either frustrate you or put you to sleep depending on your mathematical education. After reading every thread on this forum related to focusing, I remember most a little ditty someone posted ….. “ focus on the far, tilt for the near, then focus and tilt ‘till all is clear “. For modest architectural and most landscape applications, those sixteen words will serve you better than Merklingers’ tomes.

-- Michael Mahoney (mmahoney@nfld.com), October 23, 2001.

Merklinger's calculations can confuse the heck out of anyone. If you are looking for a practical tool to use I recommend Bob Wheeler's Vade Mecum software package. The tilt and focus and do it again method still gets used for most of my photos. Having Vade Mecum in the pocket does help when frustration takes over. A few quick calculations and you sometimes realize you are trying to get things in a plane of focus that simply can't be done. Vade Mecum has four methods to calculate tilt and a host of other useful tools.

-- Dave Schneider (dschneider@arjaynet.com), October 23, 2001.

Hey Dave woulnd't have been great if he had put the manual in word instead of PDF? Any way, Dave is correct this little program does all the calculations very easy.

-- Jorge Gasteazoro (jorgegm@worldnet.att.net), October 23, 2001.


If you would like to use Merklinger's approach, it would be easiest if you hired a could survey crew to map the scene and make the calculations.

-- Ken Burns (kenburns@twave.net), October 25, 2001.

I don't share the opinion expressed in this thread concerning the lack of clarity of Harold M Merklinger's writings. His Hinge rule is, in my opinion, a simple and efficient way of determining the tilt angle. Moreover his QuickTime movies helped me a lot to understand the effects of the various view camera movements on the position of the plan of sharp focus.

-- matthieu ls (lstrauss@infobiogen.fr), October 26, 2001.

If you get caught out in the field without all the formulas and gizmos, you might try a peek at the ground glass. It will show you what happens when you move something.


-- Doug Paramore (Dougmary@alaweb.com), October 26, 2001.



-- Ellis Vener Photography (ellis@ellisvener.com), October 26, 2001.

To answer the original question, I doubt that there are manageable equations to deal with a simultaneous tilt and swing. The spatial geometry is quite complex and not easily described by the two angles. An acceptable approximation could be to use the tilt equation independently on both axis. In fact, working independently, and sequentially on both axis is what I have found the simplest with visual methods. Personnally I prefer visual methods based on the GG (as explaned in great detail on the LF page). With the use of a simple gizmo (a ruler) these methods are technically optimal rather than relying on guesses.

-- Q.-Tuan Luong (qtl@ai.sri.com), October 26, 2001.

The easiest way I've found to usetilt and swing, especially in a studio setting tho that doesn't really make a difference except of the pain of lugging a big camera outinto the world, is to use on e ofthe Sinar P series of ccameras; the P, P2, X , C or C2. thebuiltin tilt and swing angle finder aids really come into their own in this kind of situation. You can improvise an assymetric swing set up by shifting the rear (or front or both) standard(s) sideways by few cm. Focus on a point on that new axis and then swingthe opposite side ofthe standard till the next point you want to come into focus does. Now recheck the focus atthe first point to make sure it is still in focus, you might need to tweak the focus a little. With the Sinar P rear standard this isn't necessary. A yaw free base tilt, or an assymmetric tilt mechanism (like on the Sinar P, I don't know if there are others) makes combined tilt and swing movements much easier over tilt designs that are not yaw free. the basic design which makes a camera yaw free is to have the swing mechanism above the tilt mechanism, not all base tilt cameras are yaw free and by definition axis tilt cameras cannot be.

One thing i have found using swing and tilt cameras is that once you combine movements you often need to refocus the camera in the opposite direction than you might think to get the optimum placement for keeping your f-stop in the optimum range for best lens performance (generally I find this to be in the f/16 to f/22.5 range).

-- Ellis Vener Photography (ellis@ellisvener.com), October 26, 2001.

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