Much use was made of computer enhancement in the early 1970's in an attempt to extract useful data from poor results. Unfortunately the investigators carrying out the photography frequently failed to recognise photographs of the loch bottom, or silhouettes of debris photographed against back-illuminated silt clouds, leading to a number of false dawns. Technicians carrying out the enhancements, which were ground-breaking 25 or 30 years ago, were equally unfamiliar with the underwater environment in Loch Ness,
Today, with the aid of a domestic computer and basic imaging software, almost anyone can "enhance" certain qualities of any image to their hearts content, whether it be brightness, contrast, sharpness, or other more subtle qualities. Back in the 1970's few researchers knew what an underwater picture looked like, even fewer had seen the bottom of the loch.
Below are four video frames taken recently. The first two are simply frames taken during the camera's descent to the bottom, original condition on the left and "computer enhanced" on the right. The two below show the bottom itself with its typical occasional lighter patches. These enhancements have each been made in a matter of a few minutes, and are merely illustrative of the difference a few key strokes on a computer can make to an image.
Particles in the water during descent Same picture "computer enhanced"
Typical view of loch bottom Same frame "computer enhanced"
In their enthusiasm, some researchers made errors of analysis. Some have been admitted, some have not. In my view no underwater photograph from Loch Ness yet published shows any part of any unclassified animal. To complicate things further, our recently gained knowledge about seals in Loch Ness throws an amount of confusion over any future photographs which might be obtained, as even the best of these will need to be shown not to be any part of a seal.
...and if you prefer them in colour
Unenhanced still frame of loch bottom
same image as above after contrast increase
Early picture of loch bottom