Steve Johnston , Sep 02, 2010; 05:20 a.m.
RAW is often referred to as the Digital Negative. Say for example, you saw a ghost or a UFO and you had your SLR with you.
If you shoot in jpeg, you could have made the alterations to the file, say cut and pasted the UFO and no could tell the difference from the file.
When you make alterations in RAW it storing the data in a sidecar file. If you delete the sidecar file it deletes the alterations.
However is it possible to make changes to actual file itself, like you would with a JPEG, and fake the UFO in the RAW file. Or is the RAW file unchangeable, So if I capture a picture of a UFO or Ghost in raw it can’t be disputed ?
Hector Javkin 
, Sep 02, 2010; 05:30 a.m.
Just ask the little green men in the UFO to change the raw file for you. It's not that difficult.
Jake Watrous , Sep 02, 2010; 06:04 a.m.
As far as I know, anything digital can be hacked to some extent. I imagine given enough time you could even write a RAW photo with "1" and "0" repeated a few kajillion times. The crux of the matter is whether it is easy to do so or not, which I imagine extensive modifications like you suggest aren't easy for most.
As far as film negatives go, those are "hackable" too. That's how they managed to make the film photos the astronauts took on the moon look like they were made on a Hollywood movie set.
Hector Javkin , Sep 02, 2010; 06:28 a.m.
If the green men refuse to do it, it could be hacked digitally, or faked the old-fashioned way -- creating the fake image in whatever format, printing it, and then photographing the print in raw.
Matt Needham , Sep 02, 2010; 08:36 a.m.
Even if your neg or file is determined to be unaltered that doesn't mean we can't dispute what's captured on it. Photography is realism, not truth.
Mikael Karlsson 
, Sep 02, 2010; 10:00 a.m.
There are verification systems used sometimes by law enforcement. I know Canon have a system like this as I have used it on occasion. I don't see these systems in use much though, even by dedicated CSI photographers. I've had images used in court numerous times and the issue of if the digital file is original or not has never come up. That doesn't mean it can't - or won't - be an issue.
Since many (even big city) CSI units, Crime Labs etc don't use the digital verification systems it certainly seems that from a legal standpoint the legal people with the PDs don't feel it to be necessary. Like mentioned previously though, anything can be hacked I believe.
Ghosts and UFOs though? Well. Who knows.
Michael Axel 
, Sep 02, 2010; 10:01 a.m.
There are photo forensic experts that can often tell. The tell-tale sign might be as simple as the pixels in the UFO differ in size, noise, or other characteristics from the surrounding area. So while you can fool some of the people some of the time, you can't fool everyone (I like breaking metaphors<g>).
Mark Deneen 
, Sep 02, 2010; 10:22 a.m.
RAW is nothing but a file format. Any decent junior programmer could write a program that would allow you to make changes directly to the RAW file, and no one would know if it was an "original" or "modified" file.
Brett Cole , Sep 02, 2010; 11:55 a.m.
RAW is nothing but a file format. Any decent junior programmer could write a program that would allow you to make changes directly to the RAW file, and no one would know if it was an "original" or "modified" file.
This is not so - link
JDM von Weinberg , Sep 02, 2010; 01:29 p.m.
Brett, that is a very useful Canon article on data verification. Of special interest is how to "switch on" the functions on the camera. No new equipment is needed by the photographer -- the verification hardware has to be bought by the user of the pictures....
from the article at Brett's LINK:
The following cameras are compatible with the Canon Data Verification kits. The information in brackets shows the Personal Function or Custom Function number needed to activate the data verification system:
EOS-1Ds (P.Fn-31)
EOS-1Ds Mark II (P.Fn-31)
EOS-1Ds Mark III (C.Fn 1V-15)
EOS-1D Mark II (P.Fn-31)
EOS-1D Mark II N (P.Fn-31)
EOS-1D Mark III (C.Fn IV-15)
EOS 20D and 20Da (C.Fn-18)
EOS 30D (C.Fn-19)
EOS 5D (C.Fn-20)
Personal Functions (P.Fn) can only be set from a computer.
The copyright date is 2010; but some cameras, the 40D, for example, are discussed later so the list above is not complete. Just for the heck of it, I have turned it on my cameras, but I haven't yet tried to see how much bigger, if any, the files are with this turned on.
