Hi again Andy,
You knew I wasn’t done, right?
The more I think about digital images, and manipulation, the deeper
the rabbit hole gets.
I gave a talk about digital imaging and image manipulation at SNAG,
back in 1996. While the technology has certainly moved light-years
since, the fundamental issues remain the same. Essentially, where do
you draw the line in how much ‘polishing’ is too much?
There are some real puzzlers involved in all this, and photographs
of jewelry type objects have the greatest concentration of conundrums
out of any subject I can think of.
So, you want to create an “accurate” image of a piece. OK fine, but
what’s “accurate”? “Accurate” to what the camera saw, or "accurate"
to what a human eye would see in the same situation? There’s no way
to create an image that’s a 100% perfect recording of the object in
front of the camera without screwing with it in photoshop. You
just can’t. The camera’s sensors don’t have the dynamic range, the
lenses distort the image, the list of shortcomings is long, even with
pro- level gear.
Jewelry, being small and reflective, is sort of the ‘perfect
trainwreck’ of nasty shooting issues.
To whit:
Reflections. Yeah, we all know this one is a PITA, but it’s even
worse than you think: ever wonder why you have to work so hard to
get your diamonds to sparkle the way they do to your eye? Simple: the
camera has one lens. You have two eyes. Your eyes are 3 inches apart,
so they’re picking up two entirely different sets of reflections.
Your brain merges them together, so that you ‘see’ both sets as
though they were one. No way on earth to photograph that. The only
way to pull off something similar is to merge two photos with
slightly different reflection sets together in photoshop. No, it’s
not anything like “accurate” to what was in front of the single lens
of the camera, but it’s a pretty good fake for what a person’s two
eyes would really have seen.
It’s not just stones that show this problem. Any reflective surface
will do the same thing, and the closer you get to the subject (like
if you’re shooting jewelry…) the worse it gets. Don’t believe me?
Take a polished ring, put it on the table in front of you, and look
at it from 6 inches away. Now close one eye. Notice that the
reflections ‘moved’? Switch eyes. Notice that they moved again? Now
open both eyes and really look at the reflections. If you’re good at
it, you can pick which eye you’re paying more attention to, and
’move’ the reflections around just by concentrating on the image from
one eye or the other.
Yes, your brain is photoshopping the image on you.
So, is the goal to make a photograph that’s an accurate reproduction
of what a machine recorded, or what a person would have seen?
Can’t even do that in one shot, really.
Dynamic range: camera sensors are getting better, but they’re still
not anywhere near as good as the human eye is, in terms of the
ability to adapt to areas of dark and light in an image. (AKA dynamic
range) The eye has tremendous range that it can cover. What’s worse,
the brain steps in again, and ‘builds’ synthetic contrast
automagically. Essentially, the brain picks the darkest area in a
scene, and defines that as ‘black’, and then picks the lightest area,
and calls that ‘white’, and stretches out the luminance range between
that to give as much contrast as possible, regardless of what a light
meter might have picked up objectively. (Pretty much exactly what you
do by adjusting the levels in photoshop.) The brain also has the neat
trick of ‘remembering’ high and low value images in stages. It picks
up the bright areas, locks those into memory, and then resets the
eye, and picks up the dark areas. Once it has both sets of data, it
paints them into one semi-coherent image that you ‘see’ as though it
were all happening at once.
So, once again, your brain’s photoshopping the image without telling
you about it.
You can do this exact same thing in photoshop, by combining two
differently exposed images to get one image with improved dynamic
range. So is that ‘altering’ the image? or is it just fixing an image
previously crippled by the limitations of the recording gear?
The lenses distort the image slightly. Photoshop can correct for
this, if you’ve got the right distortion map for the particular lens
you shot with. (not as hard as it sounds.) Is that ‘altering’ the
image? or again, just fixing a screwed up recording?
And then, of course, there are the limitations of the viewing media
of the image. Yes, you can have ‘perfect’ data stored in a file
somewhere, but it doesn’t do any good unless someone can see it.
Which means it must be displayed. Which means you have to take into
account the gamut, dynamic range and aspect ratio of whatever you’re
displaying/printing on/with. Which opens up a whole new can of
worms.
So, do you keep massaging the image data to give you…what? What’s
the intent for the final image? Once you start down this road, where
do you stop?
What’s “honest” and “accurate”?? I can make a case for just about
any image modification you care to name short of outright
fabrication.
As I said in the last post, if I’m trying to do a semi-accurate
picture of a specific piece, I’ll do anything I like to the
background, but not alter the piece itself. Much. It’s the "much"
that’s the killer. Yes, I’ll always adjust the contrast and dynamic
range. That’s standard, and the eye does it automatically. I rarely
go to the trouble of shooting multi-angle reflection shots. Major
pain in the tail. Only worth it for specific shapes and situations.
(try shooting a reflective hemisphere sometime…) But I’ll usually
remove dust bunnies, even if they’re on the piece, as those are
artifacts of the specific shooting situation, not the piece itself.
Those sorts of things get removed, even if they involve retouching
bits of the piece.
Now that you’re ‘fixing’ parts of the piece itself, even if only
dust bunnies and bad reflections, where do you stop? Where’s the line
between an “accurate” photo and a digital painting?
The other question is: does it matter? PR shots are all retouched to
the max, as a matter of course. Reality isn’t close to good enough.
What’s the purpose of the image? If the purpose is a PR shot, then
you simply don’t have a choice. Grab the Wacom tablet, and get busy.
If it’s documentation, do you bother doing anything at all?
At a certain point, the sheer overhead of time and expense involved
in massive retouching limits how much truly insane work is going on.
It takes time, and skilled retouchers don’t come cheap. Time and
money are the only limiting factors though. Any thoughts of 'honesty’
in images went out the window a decade or two back, at least in the
big leagues. Any photos that are close to ‘as shot’ are that way
because the photographer was very good in the first place, not
because anybody had the first thought for making an ‘honest’ image.
Do enough retouching, and you discover that its usually cheaper and
faster to just shoot it right the first time, rather than spend hours
tweaking around in photoshop.
FWIW
Brian