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RE: Digital camera, legal or not for documentation

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For general photographs of in-construction work a digital camera is
invaluable both for us as engineers and for contractors to illustrate
construction problems to the project team.  Typical camera resolution is
usually enough to get the point across.  Items that are in shadow and/or are
hard to see, i.e. cracks in concrete, special finishes etc do not show up
well in digital form without using a very high resolution (huge files).  For
sensitive work like this, emulsion film is still the best solution.

If you are concerned about taking photos for legal documentation purposes,
emulsion film can be used.  You can pay a little extra and have the pictures
converted to digital format and burned on a CD in addition to getting the
prints. I suppose that you could probably get a setup where you get the
negatives, a CD and no prints.  Easy to search for images, not much physical
storage space required for the negs and CD.

Barring any response to the contrary from our lawyer friends, if you use a
digital camera and burn the images to a CD, the date stamp on the CD for
each file should be enough to prove that the photos were at least taken at
the right time. An experienced graphics person can usually tell if a file
has been altered.  You have to pay an awful lot of money to manipulate
digital images so that it is hard for an expert to tell if the image has
been altered.

Nick Blackburn

-----Original Message-----
From: Christopher Wright [mailto:chrisw(--nospam--at)skypoint.com]
Sent: Friday, November 16, 2001 7:13 AM
To: SEAOC Newsletter
Subject: Re: Digital camera, legal or not for documentaion


>Is anyone NOT using digital cameras because they might not hold up in
>court because they could be altered.
I don't use a digital camera, bnut alteration is only a marginal
consideration. The major issue I could see raised would be that there's
no actual original image, as there would be with film, hence no audit
trail. In theory the camera memory card is an original, but it's very
easily and normally altered and over written or re-used.

Anything can be altered, although film negatives are tricky in this
regard. One way is to scan the original negative to disk and bugger the
image in your software of choice. Then photograph the buggered image or
scan the negative of the buggered image to film. This takes some effort
but it's plenty doable. It's also plenty fraudulent and could easily
amount to a major career decision.

If I'm doing exhibits from photographs, I scan a print to disk and crop
it or re-work certain areas for emphasis. I'm pretty careful about
explaining that something's been enhanced and why and I also add text
annotations both for my convenience and so it's apparent that I'm not
trying to pull a fast one. I keep the original negative and print around,
as part of an audit trail in case opposing counsel makes an issue of it.

Christopher Wright P.E.    |"They couldn't hit an elephant from
chrisw(--nospam--at)skypoint.com        | this distance"   (last words of Gen.
___________________________| John Sedgwick, Spotsylvania 1864)
http://www.skypoint.com/~chrisw


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