....an observation : -- I posted a photograph entitled 'Beauty In The Flame' ( see my gallery ) yesterday on Renderosity and also on another site (Artsig )... I took many shots of a windblown flame that was in front of a fancy restaurant -- ( about a year ago ) was just hoping to get some interesting shapes I could either use 'as is' - or as a starting point for a ' post worked' composition --as it turned out - the one shot looked like a girl's profile and I posted it as such ---did not touch a pixel of the flame form ---- unfortunately with digital - there's no negative to prove this point....anyway - what I thought was interesting -was that commenters on this site seemed to accept my statement of no post work ( thanks ! ) --- whilst on Artsig the first commenter wrote:

      "I hope you try not to say that women made of fire. Nice ps work in your image. RESPECT "

....this was after I had stated there was no postwork.

.....so , anyway - thanks to those who accept my word on this site --- hopefully I've built some integrity along the way - even in the face of deleting a ton of images - and galleries!  -- so - thanks to those that understand  ( or try to ! )    -  Doug

A raw file is as close as you can get to a negative. I currently don't know a way to create one in software.

And having a negative doesn't really prove anything. Image manipulation isn't something that was inventented with the onset of the digital darkroom you know ;)

....but a raw file can be manipulated - how could you prove it wasn't adjusted --- but I don't see how you could change an actual film negative - in the trad darkroom , of course -- but doing fine tuned changes on the actual negative ? -  I don't think so .

Ummmmmmm, how to manipulate a traditional negative, you ask? 

(1) shoot the original image

(2) manipulate that image

(3) make an Interpositive (Master Positive)

(4) make an internegative

See ... easy ... LOL

--
MGD

p.s. Google had 32,800 hits on 'internegative'

 ....good point MGD ! ....yeah -- I guess when you get down to it - there's no way to prove beyond a shadow of a doubt that an image was not manipulated in a certain way--- so - I would suppose it just comes down to the integrity of the photographer in his assertions of how it all came down........and --- ah --- Google is frickin' amazing.

When you manipulate a RAW file you can no longer officially save it as RAW - you have to choose between the standard formats (TIF, jpeg, PSD, bmt, etc.).

What you could do for this person is get a screen capture of Adobe Camera RAW opened with your image - circle the flame that is shaped like a woman. If he/she doesn't believe you then, they are just looking/finding any reason to argue.

I worked in a pro-lab and made internegs on 4x5 and 8x10 sheet film - yeah, you can manipulate and hide your tracks if you work at it.

And also, I knew a guy who specialized in - not kidding - airbrushing large format negative and transparencies! You CAN doctor the camera original if you're daring enough - scared the piss out of me, so I made internegs ;-)

Someone claiming to be unstrung65 mentioned that

there's no way to prove beyond a shadow of a doubt that an image was
not manipulated

Actually, with digital files, there is a way ... one of the applications of public key
cryptology is to compute and apply a digital signature to an information file. 
That signature is computed from the image file content, could include the file
name, date, time, camera model, and serial number, is traceable to the originator
(camera operator), and is easy to verify.  Any change to the image file would
cause the signature verification to fail. 

The software in the camera could create such a digital signature and imbed
it as part of the image file.  Image processing software would need to be able to
recognize and process that additional information. 

If this kind of enhancement hasn't already been done, I expect to see this
methodology become available for forensic and evidence applications. 

In store surveillance software is able to do this now -- that computation is done
in the PC as the images are recorded; and verified as the images are replayed. 

--
Martin

.....thanks for your input - thundering 1 --- to be honest - the raw format is new to me - there's also the new DNG raw format called a digital negative - which allows you to keep the original 'raw' file -- but I'm not that clear on how this system works ----as to proving to the person who doubted my photo was not altered - I could care less what he thinks ----- what I find interesting ,though - would explaining the process by which  a particular image was arrived at to an observor..............I manipulate photos all the time - ( as do we all from the moment we pick up our camera ) ---- there is no such thing as 'straight' photography and never was -- and this digital era just complicates explanations  to the point where the layman hasn't a clue what he's really looking at ! ......

...to MGD -------- yeah - it's possible I'm not unstrung65 - ( food for thought --- saw Invasion of The Body Snatchers one too many times ) ------- interesting observation on applying a digital signature -- never thought of the fact that crime 'evidence'  photos could be faked ....and probably have been --- maybe such photographers and photo journalists would have to legally use this system in the future -- but there would always be work around methods found for those of dubious integrity                      
                                                           --- possibly unstrung

Something pretty cool - maybe a bit OT - someone at MIT has come up with an algorithm to apply to digital images to check if original computations have been "altered". I don't know how it works, but there's some form of mathmatical irregularity when any pixel from a camera file has been "changed" - this is particularly important for courtrooms - evidence is now being shot with digital cameras, and authenticity is being questioned by defense attorneys.

Leave it to bickering Lawyers to result in new technology, huh?
-Lew ;-)

I think that thundering1 said,

Leave it to bickering Lawyers to result in new technology, huh?

... or try to suppress it. 

--
Martin

Attached Link: Blowup (1966)

In that film, a photographer accidentally photographs a crime scene

... but doesn't realize it until after he studies and blows up the negatives.  

--
Martin

p.s. I have been told that after this film was released, it was very difficult to
keep purple seamless paper in stock. 

You will know what I mean after viewing the film. 

Haha!
-Lew ;-)

I gotta go watch that now!

...ahhh --- Blow-Up ---haven't seen it since it came out - back then wasn't that interested in photography -or plots ! , it seems ---what I recall is the appearance of The Yardbirds doing 'Stroll On' ---which was a reworked version of their blues classic 'The Train Kept A Rollin'....Antonioni wanted that song but for some reason they couldn't use it - so they wrote new words on the spot but  used the same tune.....................but I digress.

Attached Link: Blowup (1966) as listed on amazon.com

One of the reviewer comments on amazon.com includes ...

"Pictures don't lie" is another old bromide being put to the test by
this film's unique thematizing of the photographic process itself 

This message thread, the comments about "Blowup", and the movie
itself -- all spinning around related ideas. 

--
Martin