What is perfect exposure?

Question

Is there a perfect exposure that all these die hard film users keep blabbing on about? "Get it right in camera!" Well what is the correct exposure? What is the correct exposure for caucasion skin? What is the correct exposure for grass? What is the correct exposure for white snow? What is the correct exposure for volcanic soil? Does anyone actually know? It's all very well saying "Use a grey card" but we can't even agree whether it's supposed to be 12% or 18% grey. And assuming it is 18% grey, at what zone is grass meant to be? Actually, what part of what zone? It's all very well saying caucasion skin is meant to be zone 6, but what is zone 6? One stop above 18% grey? Because Ansel Adams said so? So those fashion photographers who "over expose" skin tones are doing it all wrong then? And the award winning photographers who have skin tones in the zone 4 - 5 are actually useless?

Or are these film photographers who are constantly going on about the perfect exposure actually looking for the attention by crying out "Look at me! I'm really good at photography!"

As far as I'm concerned, the right exposure is what the photographer is looking for, not what Ansel Adams said it should be. Ansel Adams is a legend but I think he's worshipped too much.

Jules - "You have to know the rules before you can break them." Yes but do we actually know what the rules really are? If so, do we know if these rules are actually correct?

Edwin - imagine you believed Farraris came in many colours. Then some people keep going on and on and on at you that you don't know anything about cars because Farraris only come in red. Even though you have seen for yourself that they come in yellow, blue and black. Finally you get sick of it and speak your mind. That's the tone with which I'm writing this :-)

Edwin - that's an excellent answer.

MixedMojo - I like your approach. Another excellent answer

Dr, my point exactly! And as for deciding which image is from what format, you should have asked at the beginning of the answer because I took note of how you made each image while viewing them :-)

Answer 1

Books have been written on this subject. Books and more books. We could debate this for the rest of our lives. I suppose there are some techno-oriented photographers who will say something about capturing the greatest dynamic range possible with every zone represented or what have you, but I say that the perfect exposure is the one that conveys what you wish to say or show with your image.

For instance, as you well know, there are times when a shot SHOULD be dark and moody and others when it should be bright and cheery. There is a fine line between a "high key" image and one with blown highlights.

Some of my own examples...

http://www.flickr.com/photos/samfeinstein/2074567759/ has a lot of detail lost in the shadows, but what _I_ wanted to capture was the backlit flag blowing in the breeze, To heck with the rest of it. To me, the exposure is perfect. (No, it's not level, but I explain that away in my comments.) My brother "corrected" my "exposure problem," but I just don't like the end result. He pulled out a lot of detail from the trees that only serve to distract the viewer, in my opinion. http://www.flickr.com/photos/samfeinstein/2077000508/

This image shows 2 views of the same scene. (Ignore the one with the leaves for now...) http://www.flickr.com/photos/samfeinstein/2070390521/ Which one is the "right" exposure? I like each for its own reasons.

This is one of my personal favorites of all time, but what is technically "right" about this exposure? NOTHING! http://www.flickr.com/photos/samfeinstein/1466922266/

It was taken within a half an hour of this one: http://www.flickr.com/photos/samfeinstein/1466913536/ which I really like also,

Which one is "perfect?"

I could have set up lights (if I HAD any!) to get a "perfect" exposure of Ben Franklin, but this conveys the feeling of the dark room where the statue sits better than a well-lit image would. And, my gosh! There are some blurry people in the shot! http://www.flickr.com/photos/samfeinstein/441244806/

Since the sun was already actually set when I took this shot, the exposure was "pure cr@p," but I "made it work" in post. http://www.flickr.com/photos/samfeinstein/1246203186/ I think it is better than if I had captured every zone in a well-lit scene.

There is nothing perfect about these examples, but I wouldn't change a thing:
http://www.flickr.com/photos/samfeinstein/1089705218/
http://www.flickr.com/photos/samfeinstein/856121089/
They were taken 26 and 36 years ago and I still rank them among my "personal best."

And by the way, if we want to play the film vs. digital game, see how you do without looking at the exif data - if you can help it.

4 of these were taken with a 10 MP point and shoot.
1 of these was taken with a 4 MP point and shoot.
2 of these were scanned from 35 mm slides.
2 were scanned from 4x6 prints made from 35 mm film.
1 was taken with a 10 MP digital SLR.

Answer 2

Use a grey card...

I don't even use a grey card, I use whatever neutral tone [in my scene] textured enough for my D80's autofocus to lock onto, and that's often an area of asphalt, or other pavement closest to me. Works for me. I think that the blabbing comes from resentment some folks have of the relative ease of modern photography. I mean lets face it, things that are done today are not done the same way as they were as little as 10 years ago. Sure, we all need a basic foundation and understanding of exposure, but nowadays that can be learned from spendinng half an hour reading a few chapters of a book found in any Barnes & Noble scattered across the country. That doesn't make the photographer though, we learn how to take proper exposure reading from eventually coming to understand and trust our camera's light meter, only 20 years ago you had to do so blindly, having to wait a period until you could see the fruits of your labor from the darkroom or the lab. Well, things are no longer done that way. So when I hear that expression, 'get it right in the camera', I usually tend to dismiss it if not chuckle a bit to myself. You think Anne Geddes, or Annie Leibovitz gets it right in the camera, everytime? No, because they shoot digital, just like me. Sure, they probably do large or medium format film as well, but the standard is digital now. So, get it right, when you get it right. Take a hundred shots if neccessary, but eventually through practice and patience, you will get the shot right. Most folks that speak of "getting it right in the camera", usually bracket anyway. So, what's the point? Just what is "right" and "wrong" anyway? If you ask me, I say it's subjective. People do what works for them. You go to school to learn "how" and "what" to do, then you develop your own style which may differ from convention. Who cares anyway? I certainly don't.

...My two cents worth anyway

Answer 3

I think you kind of answered your own question there...

Photography is an art, not a science.

The correct exposure is whatever makes that particular image look its best.

I think of myself as more of a digital image maker than a photographer. I think all this over specialized analysis of zones and grey percentages is a throwback to the days when photography was a substitute for painters, and they were only interested in capturing the world 'perfectly'.

In my opinion, this is no longer relevant, and I just want to create powerful images.

But that's just me anyway.

The only other argument for it would be, that as with most arts (or even most things in life) - you've gotta learn the rules before you break them.

Answer 4

First, I have to admit that I really don't like the tone of your question. IMO its a bit antagonistic. However, its also of interest.

A "perfect exposure", were there such a thing, would produce an image with no blown highlights and no blocked-up shadows. The tonal range would be from pure white to pure black with every shade of gray between those extremes. The ''perfect exposure", then, is a goal to be sought although seldom actually achieved.

When a traditional photographer (a fancy title for us film users) says "Get it right in the camera" its a rememberance of the days of using slide film. With slide film there is approximately +/- 1 stop of exposure latitude. Exceed that and the resultant slide is useless. Print film is more forgiving of exposure errors, often with 3 or 4 stops of latitude.

"Get it right in the camera" is also an exhortation for the photographer to do the thinking rather than depending on the camera and/or extensive post-processing with a computer program. IMO, when someone says "Oh I can fix it in Photoshop" it indicates that they really don't know how to use their camera to its full potential. (I own 3 Minolta X-700 cameras. The X-700 has Aperture Preferred or Manual or Program Mode. In Program Mode the camera selects both aperture and shutter speed. I've never used it since I know the camera will choose a higher shutter speed over a smaller f-stop and, since I usually like more depth of field, the results may not be what I want. So I shoot in Aperture Preferred and pay attention to the shutter speed selected by the camera. If I'm feeling really retro I'll use my elderly SRT-202 and set both.)

As to your puzzlement over 18% gray or 12% gray, again it goes back to film. With film, 18% gray was established as being the average reflectance of an average scene. I haven't delved into why manufacturers are calibrating their meters to read 12% gray but its likely something to do with how a digital sensor responds.

Suppose we are photographing a snow scene. If we rely solely on the camera to determine the exposure our snow will not be pure white. It will be a shade of gray since the meter is basing its calculation on either 12% or 18% gray. While it may be possible in post-processing to make the snow white, the knowledgeable photographer knows to use +1 or +2 EV to "fool" the camera and produce an image of pure white snow. He or she "got it right in the camera".

Suppose we are faced with a scene with part of it in bright sunlight and part in shade. If we rely solely on the camera the highlight area will be blown out and the shadows will be blocked up. The knowledgeable photographer sees this and knows that some compensation is needed. So he or she will take a reading of the shadow area and one of the highlight area. Suppose the shadows need f2 @ 1/125 and the highlight area needs f8 @ 1/125. If you count f-stops up from f2 and down from f8 you arrive at f4 @ 1/125. In this situation the savvy photographer will make 3 exposures - 1 at f4, 1 at f2.8 and 1 at f5.6. This is called "bracketing". Again, the photographer is making every attempt to "get it right in the camera".

Photography is subjective, not objective.

subjective: adj. of or resulting from the feelings of the person thinking; not objective; personal

objective: adj; 1. existing as an object or fact. independent of the mind; real. 2 concerned with the realities of the thing dealt with rather than the thoughts of the artist, writer, etc. 3. without bias or prejudice.

Definitions from "Webster's New World Dictionary".

Perhaps we should all just hang our hats on what Robert Capa said: "I would rather have a strong image that is technically bad than vice versa."

Answer 5

With film it means no blocked highlights and no emulsionless shadows. A nice, fine graduation from black to white.

With digital, it means get it right in the camera. Shoot digital with the same care that you would shoot slide film. Expose for the highlights. Once that pixel value goes to white or 255 you cannot ever retrieve that image data...not even photoshop will bring it back.