Coming to terms with exposure compensation requires understanding basic ambient exposure first. Ambient exposure is made of a combination of shutter speed and aperture (assuming no flash is in use). Using basic daylight (called the sunny 16 rule by some) your base exposure can be quickly calculated by combining f/16 and the reciprocal of the ISO in use (this is a sunny day exposure). For example, with ISO 100 film, your exposure should be 1/125 at f/16, or any combination that equals the same value (i.e. 1/60 at f/22 or 1/250 at f/11). This by the way, is an easy way to determine on your own if your camera meter is providing accurate readings. With your hand fully lit, take a meter reading off it and it should equal basic daylight (within 1/3 stop)....Show more →
This is something I found on the net... and I am trying to understand this...
Actually , the Sunny 16 Rule dictates that in full sun between 10:00 and 2:00, the exposure at ISO100 is 1/100@f16.
There were multiples for open shade, overcast days, etc.
Some of us old timers used to refer to that rule as "Basic Daylight Exposure" and every lighting situation thus had an exposure that was based on that "BDE".
The premise is that light acts very predictable ways. In nature the sun provides a consistent source of light under certain conditions. If it didn't we all be in trouble more ways that one. The Sunny 16 settings assume that the sun will provide a consistent repeatable exposure at mid day when there are no clouds to act as a modifier. Even "cloudy" or "shade" provides consistent repeatable light reading. This condition is found anywhere under the sun and nothing changes under the sun.
It's nice how everyone reminds me "I am a beginner".. thanks. I know and understand this.
I guess I will go and look to google for a more detailed answer...
<sigh> should have know better to post something like this.. at least here.. It's amazing that I have gotten any results at all with my camera not knowing such "vital" information..... : )
sharp_glass wrote:
It's nice how everyone reminds me "I am a beginner".. thanks. I know and understand this.
Don't take it personally. You can be photographing for a long time and never realize that you're getting basically the same exposure in many different places. And the relationship between aperture and shutter speed was much easier to grok when they were printed on the outside of the lens and camera, and you could see how they moved together. Some people forget that there ever was a time when they didn't get it.
Thanks.. I just want to keep learning.. I know this is an "advance" forum.. so I should take that into consideration.
So lets see if I have learned this... ....
Basiclly during bright sunny days (especially here in Miami) I can just go ahead and set my lens to f/16 , and I know that on a bright day I am going to be using ISO 100. So based on the rule, I want to get my shutter speed close to the ISO setting.
So.. maybe f/16, 1/100 @ ISO 100
If it's a little darker (cloudy) then start a stop down to f/11 and compensate the shutter to 1/125 still at ISO 100..
You should know the sequence of the numbers. In part (I hope these line up)(well they didn't but you see the sequence):
5.6 8 11 16 22
1/1000 1/500 1/250 1/125 1/60
Those are all equivalent, the same exposure. For more or less exposure, you can vary shutter or aperture. Or both, to a different EV (exposure value). So if it's cloudy, at iso 100, f8 1/125. Or f/5.6 1/250. Same thing, but different EV than f16 1/125.
The thing to keep in mind is the principle of reciprocity. The following exposures are all the same:
f16 @ 1/100
f11 2/3 @ 1/125
f11 @ 1/200
f8 @ 1/400
f5.6 2/3 @ 1/500
f5.6 @ 1/800
f4.0 2/3 @ 1/1000
So no need to stick to f16 if you desire a wider aperture.
jjlphoto wrote:
The thing to keep in mind is the principle of reciprocity. The following exposures are all the same:
f16 @ 1/100
f11 2/3 @ 1/125
f11 @ 1/200
f8 @ 1/400
f5.6 2/3 @ 1/500
f5.6 @ 1/800
f4.0 2/3 @ 1/1000
So no need to stick to f16 if you desire a wider aperture.
+1
the sunny16 rule is just a basic starting point to get a good exposure with the sun out during midday
jjlphoto wrote:
The thing to keep in mind is the principle of reciprocity. The following exposures are all the same:
f16 @ 1/100
f11 2/3 @ 1/125
f11 @ 1/200
f8 @ 1/400
f5.6 2/3 @ 1/500
f5.6 @ 1/800
f4.0 2/3 @ 1/1000
So no need to stick to f16 if you desire a wider aperture.
+1
the sunny16 rule is just a basic starting point to get a good exposure with the sun out during midday
jjlphoto wrote:
The thing to keep in mind is the principle of reciprocity. The following exposures are all the same:
f16 @ 1/100
f11 2/3 @ 1/125
f11 @ 1/200
f8 @ 1/400
f5.6 2/3 @ 1/500
f5.6 @ 1/800
f4.0 2/3 @ 1/1000
So no need to stick to f16 if you desire a wider aperture.
+1
the sunny16 rule is just a basic starting point to get a good exposure with the sun out during midday
Here's a different take on the topic of exposure....
In practical terms for a beginner the easiest way to learn exposure is to start in P mode and observe what the camera does to select exposure for various scenes. Depending on light level it will pick various combinations of aperture and shutter speeds. It will not always provide the correct exposure, so you need to adjust via the Exposure Compensation control (EC). The easiest way to know when exposure is correct or not is to put the playback into "info" mode where overexposed areas become blacked out.
After using P mode for awhile graduate to Av mode. Av mode allows you to select the aperture while the camera picks whatever shutter speed the meter thinks is necessary for correct exposure. As with P mode its usually necessary to "second guess" the camera results with +/- EC
You will probably use Av mode more than any other automatic one because one of the more useful creative tools in photography is the control of depth of focus, more commonly called "depth of field" or DOF to separate foreground and background. Throwing the background out of focus in a photo mimics the way our eyes focus on only 2% in the very center of our field of view and tune everything else out. So in most shooting situations other than sports where stopping action is important, the first creative decision made is what aperture to use to control foreground / background separation.
For any given lens as you increase the f/stop number the aperture gets smaller and DOF increase, but depth of the zone which is in focus will vary depending on the distance you focus on and the focal length of the lens. You can't actually see the DOF of the selected aperture in the viewfinder because the camera always focuses with the lens wide open to make the viewfinder as bright as possible. But if you press the button to the left of the lens, below the lens release button (i.e. the DOF preview button) it will close the aperture to what you've selected so you can preview the DOF.
Experiment shooting with various apertures using the DOF preview button to get an understanding of DOF control with your lenses at different distances. Many become enamored by extremely shallow DOF, but keep in mind the benchmark for "normal" is the DOF we experience with our eye balls. When DOF gets more shallow than our eyes would perceive in person in an similar situation the extremely shallow DOF can actually become a distraction rather than a means to mimic how the eyes and brain tune out the unimportant background.
In low light situations in Av mode there will be a point where the camera will select a shutter speed too slow for you to hand hold without blur. Your choices there are either to put the camera on a tripod or raise the ISO speed. When you raise ISO the camera doesn't capture more light, it simply amplifies what was captured more. Amplifying the image data also amplifies the noise, which accounts for the rainbow grain of high ISO images.
As in P mode the easiest way to know when exposure is correct or not is to put the playback into "info" mode where overexposed areas become blacked out. To get perfect exposure when shooting portraits have the subject hold a white terry wash cloth next to their face. Keep the towel 1/3 stop (one dial click) below the point where it starts to black out in the overexposure warning and your exposure will be perfect.
Once you get the hang of controlling exposure via the over-exposure warning (OEW) and those standard targets you'll be able to do it on highlights in scenes like landscapes. Most outdoor scenes will have specular, mirror like reflections off objects. So if shooting something like a white car you'd adjust exposure so the reflection off the chrome was clipping in the OEW but the white paint of the car isn't.
A couple final notes with respect to aperture:
In terms of optical performance most lenses are sharpest about 2-3 stops smaller than wide open. Full f/stops are 1.0 - 1.4 - 2.0 - 2.8 - 4.0 - 5.6 - 8 -11- 16 - 22 - 32 - 45 ... So if you have an f/1.4 lens it will be sharpest around f/4, while a f/2.8 lens will be sharpest around f/8. Beyond f/11 the aperture gets so small physically it begins to distort the light going through it (i.e. diffraction) which degrades image resolution. So unless there is a compelling need for extreme DOF its better to avoid stopping down past f/11 if possible.
Shooting outdoors with flash is a different can of worms. Click the WWW button below and look in the Canon section for tutorials I've written on fill flash exposure control and high-speed FP flash mode for shooting in sunlight at wide apertures.
FWIW - Whenever I get a new camera I do exactly what I suggest here. I first put it in P mode and shoot at random, seeing how the camera handles focus and exposure. Each new camera does it slightly differently so its a very quick way to learn the camera's baseline performance. Then I switch to Av and repeat the same shots. Finally I do it in M mode, seeing if I can outguess the camera.
sharp_glass wrote:
It's nice how everyone reminds me "I am a beginner".. thanks. I know and understand this.
I guess I will go and look to google for a more detailed answer...
<sigh> should have know better to post something like this.. at least here.. It's amazing that I have gotten any results at all with my camera not knowing such "vital" information..... : )
Well - out of three posts when you replied two had been helpful and did not remind you you were a beginner. The other post asked a question about how long you had been using a non P&S camera as most people with two DSLRs would have some idea of the concept which was defeating you. Categorizing this however as "everyone" is a bit over-sensitive in my book.
But why are you worrying about this "rule"? The reason cameras have meters is so you don't need guesswork - although interpreting the meter results is a whole new ball game of course!
paulhodson wrote:
Well - out of three posts when you replied two had been helpful and did not remind you you were a beginner. The other post asked a question about how long you had been using a non P&S camera as most people with two DSLRs would have some idea of the concept which was defeating you. Categorizing this however as "everyone" is a bit over-sensitive in my book.
But why are you worrying about this "rule"? The reason cameras have meters is so you don't need guesswork - although interpreting the meter results is a whole new ball game of course!
I was thinking the same thing Paul....talk about way over sensitive. If you ever took an art/photography class you'd probably walk out crying because the instructor would be very direct while being helpful and honest like "everyone" has been thus far. Even about P&S cameras.
It is important that you understand that nobody here is trying to make a fool out of you when they call you a beginner. We were all beginners at one time or another. I have been into photography for more than 40 years and still I am a beginner in many areas and continue to learn.
Sunny 16 applies to 2 hours after sunrise and 2 hours before sunset although here in Miami, especially summertime, it could be longer than that. It only applies to front lighted subjects. Side light or backlighted subjects require a different exposure.
I like the books written by John Shaw where he has an excellent chapter written on exposure. I particularly like "The Confused Photographer's Guide to Photographic Exposure and the Simplified Zone System" by Bahman Farzad. This is a book with a long title but well written and easy to read and understand. It will give you a ton of information on exposure.
I live in Miami and many times I am not busy. If you feel like talking about exposure just email me to find a convenient time to review some of the basic concepts and put those concepts in practice so that you can understand this better. We have plenty of subjects in Miami to put those concepts to work.
William Rodriguez
Miami, Florida.
Shooting at ISO 100: f/16, 1/100
Shooting at ISO 200: f/16, 1/200
Shooting at ISO 400: f/16, 1/400
Shooting at ISO 800: f/16, 1/800
. . . ad infinitum . . .
Of course, as mentioned above, any equivalent exposure setting will result in a properly exposed photo, just with different DOF and motion-freezing characteristics.
....