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Author Topic: Tips for quickly positioning camera to photograph the dead centre of a cube  (Read 6561 times)

Eric Kellerman

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I have been photographing people interacting in a cube (with the side facing the camera removed). It takes me quite some time to get my camera+tripod set up correctly to find the exact centre of the cube in all three dimensions (sort of analogous to yaw, pitch and roll). So far I have been doing this by eye, but this 'technique' is not exact enough and necessitates subsequent correction of horizontals and verticals in PS. How do I achieve perfectly symmetrical perspective in foolproof fashion? Any tips gratefully received.
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BartvanderWolf

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Re: Tips for quickly positioning camera to photograph the dead centre of a cube
« Reply #1 on: September 29, 2013, 08:43:25 AM »

I have been photographing people interacting in a cube (with the side facing the camera removed). It takes me quite some time to get my camera+tripod set up correctly to find the exact centre of the cube in all three dimensions (sort of analogous to yaw, pitch and roll). So far I have been doing this by eye, but this 'technique' is not exact enough and necessitates subsequent correction of horizontals and verticals in PS. How do I achieve perfectly symmetrical perspective in foolproof fashion? Any tips gratefully received.

Hi Eric,

Can you (temporarily) mount a mirror (tile) on the rear cube face?

That will allow to center your lens' reflected image in the center of your viewfinder image. When you mount the mirror at the exact center of the far cube side (using 2 diagonal lines to find that center), your camera/lens will need to be positioned exactly symmetrical in height and width, and square to the rear cube face to see that mirror image of your lens.

Otherwise, you may need to resort to very precise distance measurements, from entrance pupil position to corners, e.g. with a laser distance finder.

Cheers,
Bart
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MrSmith

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Re: Tips for quickly positioning camera to photograph the dead centre of a cube
« Reply #2 on: September 29, 2013, 09:33:06 AM »

no idea if your camera supports live view tethered in capture-1 but an overlay of a line drawing of your box would enable you to easily line up your box and the inner back square would change size as you moved back/forth until you hit the right position.
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Eric Kellerman

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Re: Tips for quickly positioning camera to photograph the dead centre of a cube
« Reply #3 on: September 29, 2013, 10:58:19 AM »

Thank you very much, Bart and MrSmith. I shall pursue both suggestions forthwith.
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alatreille

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Re: Tips for quickly positioning camera to photograph the dead centre of a cube
« Reply #4 on: September 29, 2013, 11:59:33 AM »

Eric,

I've just looked a the work you're talking about....
Striking....soft lines within a hard boundary!

Conceptually very very nice.  Is it continually progressing, or complete - you have a book out?
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Eric Kellerman

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Re: Tips for quickly positioning camera to photograph the dead centre of a cube
« Reply #5 on: September 29, 2013, 12:03:41 PM »

Is it continually progressing, or complete - you have a book out?

Thanks, Alatreille. Yes, there is a book out, published in Germany in October last year. See here. And yes, the project is ongoing!
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Ligament

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Re: Tips for quickly positioning camera to photograph the dead centre of a cube
« Reply #6 on: September 30, 2013, 12:28:29 AM »

cut 4 sections of pipe or wood the same length, and extend each from a corner toward the lens ala a pyramid. This will allow you to quickly and potentially accurately position the lens
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douglas frost

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Re: Tips for quickly positioning camera to photograph the dead centre of a cube
« Reply #7 on: September 30, 2013, 12:55:12 AM »

further to the tethered solution - when shooting architecture, i shoot tethered via camranger to an ipad. the camranger app allows you to put a grid over the liveview image. this will let you get centered and square very quickly.

regards, douglas
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MrSmith

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Re: Tips for quickly positioning camera to photograph the dead centre of a cube
« Reply #8 on: September 30, 2013, 04:58:53 AM »

cut 4 sections of pipe or wood the same length, and extend each from a corner toward the lens ala a pyramid. This will allow you to quickly and potentially accurately position the lens

You make it sound so simple ::)
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Eric Kellerman

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Re: Tips for quickly positioning camera to photograph the dead centre of a cube
« Reply #9 on: September 30, 2013, 07:13:17 AM »

Thank you, Douglas. The Camranger seems to be a very useful piece of kit.
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Eric Kellerman

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Re: Tips for quickly positioning camera to photograph the dead centre of a cube
« Reply #10 on: September 30, 2013, 07:14:40 AM »

cut 4 sections of pipe or wood the same length, and extend each from a corner toward the lens ala a pyramid. This will allow you to quickly and potentially accurately position the lens

Thank you for your idea. I just wonder about how I would temporarily attach the pyramid without damaging the box.
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Fine_Art

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Thank you for your idea. I just wonder about how I would temporarily attach the pyramid without damaging the box.

String. Pull 4 pieces of string the same length tight.

Bart's method in the second post is the most precise as long as you can align the face of the mirror parallel to the back face of the cube. If the mirror is off a little you will be way off the center. If the mirror is good you will be the closest to center.
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Fine_Art

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Just thought of the solution to the mirror. You need a second mirror with a small hole in it to look through. If you face the 2 mirrors you can align them y the multiplying reflections. Then remove the second mirror. Put the camera there. If the lens is in the middle of the frame the camera in right on.
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