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Author Topic: How do I make sure that my camera is completely parallel to a wall?  (Read 22613 times)

Abdulrahman Aljabri

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #20 on: September 03, 2010, 11:37:33 pm »

Is the inclination vial still being made? Neither B&H nor Google produced any results when I searched for it.
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NigelC

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #21 on: September 04, 2010, 09:51:39 am »

Paul,



You can use a simple lazer pointer mounted on your camera and a mirror on the wall. The reflected beam should align with the source if the camera is perfectly perpendicular to the wall.



Just so happens I have a tiny laser pointer for PP presentations - I hadn't thought to use it to align sensor plane with a brick wall - could you elaborate - I can't really see how it would prove both planes were parallel.
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Joe Behar

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #22 on: September 04, 2010, 10:45:03 am »

Just so happens I have a tiny laser pointer for PP presentations - I hadn't thought to use it to align sensor plane with a brick wall - could you elaborate - I can't really see how it would prove both planes were parallel.

In a nutshell,

Angle of reflectance equals angle of incidence...

In simple terms, if the laser pointer is anything except exactly perpendicular to the mirror, the reflected beam will not return to the point of origin.

Keep in mind please that this method needs to be used for both the front AND rear standards if you are using a view camera. That's the only way to make sure that there are zero distortions (not counting inherent distortions in the lens)
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Bart_van_der_Wolf

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #23 on: September 04, 2010, 11:08:04 am »

In a nutshell,

Angle of reflectance equals angle of incidence...

In simple terms, if the laser pointer is anything except exactly perpendicular to the mirror, the reflected beam will not return to the point of origin.

Keep in mind please that this method needs to be used for both the front AND rear standards if you are using a view camera. That's the only way to make sure that there are zero distortions (not counting inherent distortions in the lens)


Hi Joe,

Which raises the question; "How to mount it on the camera/standards perfectly square ?" ... Isn't that a chicken and egg situation?

Cheers,
Bart
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Joe Behar

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #24 on: September 04, 2010, 11:29:12 am »

Hi Joe,

Which raises the question; "How to mount it on the camera/standards perfectly square ?" ... Isn't that a chicken and egg situation?

Cheers,
Bart

Bart,

In my experience, there is a certain amount of "acceptable" error, which will be compensated for by things like depth of field and depth of focus. 

I've also found that things like flash shoes on cameras and attachments for compendiums on view cameras are pretty well close enough to square to do the job.

If your needs are such that extreme accuracy is needed, then you really have no choice but to go to a ZigAlign system or something similar.

I know that there will be the inevitable responses about specs, figures, complex math and charts & graphs to "prove" me wrong, but I tend to be pragmatic about such things and go with the what gets the job done, while maintaining more than acceptable results.

If I described the systems in use at major, internationally recognized galleries and museums I've had the pleasure to deal with, you might just faint :)



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Bart_van_der_Wolf

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #25 on: September 04, 2010, 01:15:00 pm »

Bart,

In my experience, there is a certain amount of "acceptable" error, which will be compensated for by things like depth of field and depth of focus.

Hi Joe,

Sure, no problem, I just hoped for an ingenious solution I haven't considered before. I try to keep an open mind. One thing that helps is the use of a somewhat longer focal length. It won't help the DOF but the alignment is probably better to see/measure and the angular error smaller.

Quote
I know that there will be the inevitable responses about specs, figures, complex math and charts & graphs to "prove" me wrong, but I tend to be pragmatic about such things and go with the what gets the job done, while maintaining more than acceptable results.

If I described the systems in use at major, internationally recognized galleries and museums I've had the pleasure to deal with, you might just faint :)

Not likely but I understand what you're saying. I like simple solutions, like a plumb line for vertical alignment, a tape measure at 2 distances for horizontal alignment, and mirrors for centering. Unfortunately there are often practical obstacles that prevent doing it simple, or simple isn't accurate enough.

Cheers,
Bart
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michaelnotar

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #26 on: September 05, 2010, 08:52:33 am »

this is what i do for flat art copy of paintings

measure out a set distance on the wall from the center of the painting. mark it on the wall with tape. rough in the camera to be approx perpendicular to the wall. level camera/use VF grids etc... measure distance to lens from each point on wall. when they are equal you are perpendicular to the wall. 10th grade geometry...
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Rob C

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #27 on: September 05, 2010, 11:09:06 am »

Hi guys,

I was just wondering: After having evened-out the camera so that is completely parallel to the floor - say with an ARCA cube - is there a technique with which I can make sure that the camera is completely parallel to a wall I want to photograph? Or do you guys just do trial and error?

Regards

Paul


After much thought, I concluded: glue.

Rob C


Joe Behar

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #28 on: September 05, 2010, 11:21:17 am »


After much thought, I concluded: glue.

Rob C




Rob,

Can you be more specific please?

Digital or analog glue? If its digital, what is the pixel count and pitch?

Does your glue have sufficient dynamic range?

Is the signal to  noise ration high enough at high ISO?

Do you have any DxO test results for this glue?

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Rob C

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #29 on: September 06, 2010, 03:23:30 pm »

Rob,

Can you be more specific please?

Digital or analog glue? If its digital, what is the pixel count and pitch?
Does your glue have sufficient dynamic range?
Is the signal to  noise ration high enough at high ISO?
Do you have any DxO test results for this glue?


Glue type: that special agent stuff, you know, the kind that leaves no trace.

Dynamic range: oh yes - quite flexible, possibly due to the rubber/latex base.

Signal to noise range: no; I told you, secret agant stuff: nil decibels at any volume.

DxO test results: aren't you listening - this is all classified information - think one-minute and extrapolate from there is as far as I dare go - and only for you.

Rob C 

Peter Barnes

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #30 on: September 09, 2010, 02:18:53 am »

from CBarrett
Quote
All the monitors to seventy two degrees but not on Thursdays never on thursdays.

In a misguided attempt to test the wisdom of my elders and betters I did set a bank of monitors to 72 degrees on a Thursday. Was that ever a mistake - still paying the price.
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Peter Barnes

Rob C

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #31 on: September 09, 2010, 03:04:54 am »

I'm surprised you hadn't heard that banks have been a bad bet for a couple of years, at the very least.

Rob C

teddillard

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #32 on: September 09, 2010, 09:26:08 am »

You could try sticking a tiny self adhesive mirror slap bang in the middle of the wall, or rather where you would like the middle of the wall to be. Then looking through your camera viewfinder if you can see your camera lens in the mirror you should be in alignment.

Will it work, I've no idea, but if it does then please let me know.

It will work perfectly.  And, might I add, elegantly.  :)
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Ted Dillard

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #33 on: September 09, 2010, 10:08:21 am »

The mirror on the wall works for me if it can be stuck flush to the wall (ie its a flat internal wall). Even if the wall isn't perfectly vertical the camera will still be parallel to it.

Tony May
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teddillard

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #34 on: September 09, 2010, 05:15:48 pm »

yup, and it does in practice too...   ;D

What's that old saying?  "The difference between Theory and Practice is much smaller in theory than in practice."
« Last Edit: September 10, 2010, 03:45:07 pm by teddillard »
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Ted Dillard

teddillard

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Re: How do I make sure that my camera is completely parallel to a wall?
« Reply #35 on: September 10, 2010, 09:52:33 am »

Sorry, don't think a mirror's going to help with converging judgment.   ::)
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Ted Dillard
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