Metering and where-to-point

[mrpiano]

Hi all,

I'm reading some books, namely Bryan Peterson's "Understanding Exposure" and a slew of articles on various websites, and I'd like to validate some of my findings over the last couple of days...looking for validation or any annotations on any of these "conclusions" below:

1. Pointing your camera at a white object to get a meter reading will attempt to turn that white object 18% gray if you meter off of it and do not compensate at all.
2. One approach for dealing with this is to not meter off of that object, but to instead meter off something that is in fact somewhat neutral if possible
3. Another approach seems to be to meter off of the white object, but then use Exposure compensation to about +1 full stop in order to slow the shutter back to half the speed necessary to render the white correctly (in AE mode)
4. Another approach is to shoot manual, meter off the white object, but set your exposure to +1

What's interesting is when I try any of the above techniques, especially in manual mode, when I expose against a white object to +1 and then point my camera at a neutral gray object, my meter goes straight to the middle when pointed at the gray object.

In AE mode, when I do the same exercise, when I point at a white object, the shutter speed is twice as high as when I point it at a gray object...

Am I on the right track with all this? Just trying to find the best approach for finding good exposure settings and these are some of the things I'm starting to notice consistently.

Thank you!

GG

[kencaleno]

To set custom White balance:

Select a neutral coloured object to set your white balance
It’s best to avoid using a white target. The camera prefers grey.( Print yourself a grey card: In photoshop- File> New
Click on background square in toolbox
select Red 127;Green 127;Blue 127 from color chart-Print)

If you use white in direct sunlight you'll always get a "No Gd" response from the camera because the Matrix/Evaluative meter is rendering it white instead of grey. Thus the trick is to select the centre-weighted meter when using a white reference in bright light and you'll get "Good" from a camera. Remember to set back to Matrix/Evaluative metering as soon as you're done.

PS. I cannot understand why so many people recommend Bryan Peterson's "Understanding Exposure"-he doesn't understand Exposure himself, especially concerning digital. But he is a commendable film photographer.

Regards, Ken

[fletch]

Originally Posted by kencaleno

To set custom White balance:

Select a neutral coloured object to set your white balance
It’s best to avoid using a white target. The camera prefers grey.( Print yourself a grey card: In photoshop- File> New
Click on background square in toolbox
select Red 127;Green 127;Blue 127 from color chart-Print)

If you use white in direct sunlight you'll always get a "No Gd" response from the camera because the Matrix/Evaluative meter is rendering it white instead of grey. Thus the trick is to select the centre-weighted meter when using a white reference in bright light and you'll get "Good" from a camera. Remember to set back to Matrix/Evaluative metering as soon as you're done.

PS. I cannot understand why so many people recommend Bryan Peterson's "Understanding Exposure"-he doesn't understand Exposure himself, especially concerning digital. But he is a commendable film photographer.

Regards, Ken

Did you even read the original post Ken? Not once did he ask about white balance.

Mrpiano - regarding metering I've not read the Bryan Peterson book so I'm not familiar with the techniques you are using. When faced with a tricky exposure I normaly switch to spot metering and meter off whatever is the main subject of the picture such as a persons face etc. Then I'll take a test shot and check the histogram (beauty of digital) adjusting the exposure as necessary. For landscapes I may even skip the spot metering or meter of a few different parts of the scene and then pick somewhere in the middle of the range.

That's the beauty of digital, you don't need to spend hours calcualting exposure and bracket shots to ensure that you get the shot, just take a test shot or two and check the histogram.

[kencaleno]

Originally Posted by fletch

Did you even read the original post Ken? Not once did he ask about white balance.

Mrpiano - regarding metering I've not read the Bryan Peterson book so I'm not familiar with the techniques you are using. When faced with a tricky exposure I normaly switch to spot metering and meter off whatever is the main subject of the picture such as a persons face etc. Then I'll take a test shot and check the histogram (beauty of digital) adjusting the exposure as necessary. For landscapes I may even skip the spot metering or meter of a few different parts of the scene and then pick somewhere in the middle of the range.

That's the beauty of digital, you don't need to spend hours calcualting exposure and bracket shots to ensure that you get the shot, just take a test shot or two and check the histogram.

Where are you coming from? The following from original statement is white balance:

Pointing your camera at a white object to get a meter reading will attempt to turn that white object 18% gray if you meter off of it and do not compensate at all.
One approach for dealing with this is to not meter off of that object, but to instead meter off something that is in fact somewhat neutral if possible
Another approach seems to be to meter off of the white object, but then use Exposure compensation to about +1 full stop in order to slow the shutter back to half the speed necessary to render the white correctly (in AE mode)
Another approach is to shoot manual, meter off the white object, but set your exposure to +1

[kencaleno]

Mr Piano,Here's the secret to getting a perfectly exposed outdoor shot every time - (as long as your subject area is within the 5-stop dynamic range of the camera's metering system)

1. Know how your camera handles exposure-( I know that mine overexposes between 1/3 and 2/3 of a stop-depending on lighting conditions)

First, calibrate your camera's meter:

a) Set camera mode to “P”/P-shift“, or “A/AV” Use Matrix/evaluative metering-(Scene should contain all tones within dynamic range)
b) Hold +/- button, (On Nikon’s, Near shutter button: Canon‘s is to the right of LCD screen) and turn command dial to + 1.0 - take a shot

Next ……………………………….................turn command dial to + 0.7 - take a shot
Next………………………………..................turn command dial to + 0.3 - take a shot
Next………………………………..................turn command dial to - 0.0 - take a shot
Next………………………………..................turn command dial to - 0.3 - take a shot
Next………………………………..................turn command dial to - 0.7 - take a shot
Next………………………………..................turn command dial to - 1.0 - take a shot



You will have 7 shots from + 1.0 to - 1.0 study these for one with detail in shadow and highlight areas, without blown highlights (Switch on the “blinkies” to show blown highlights)
Set exposure compensation (+/-) to this best shot reading, and keep it there for all outdoor shots
Once set up, this will be pretty accurate.

Set metering to "spot metering" mode
Set auto bracketing to 2/3 EV (With camera calibrated as above you should not be more than 1/3 EV(0.3) out at any one time)

Use A/Av mode to select depth of field

set white balance to appropriate Kelvins as below:

Where, with film you either shot print film in daylight or with flash indoors, and with slide film, you used daylight or tungsten film, or used compensating filters with these. White balance is Digital’s version-you select a white balance based on the condition of the light you are using, so the camera’s meter allows for white to photograph as white
Auto white balance does a reasonable job most of the time, but it cannot cope in some situations-especially when subject is in deep shadow. You need to know when to use the white balance settings for all situations, and this table will help you understand: ( degrees Kelvin is a means of determining colour temperature)

Sunrise/sunset 2400-3000 Kelvin……………………Use Auto white balance
Tungsten lighting 3200-3500 Kelvin ……………………Use tungsten/Incandescent white balance
Fluorescent lighting 4000 Kelvin …………… Use fluorescent White balance
Early morning/afternoon sun 4000 Kelvin…….Use auto white balance/ --fluorescent white balance
(Magenta filter) to counter greenish cast on skin from foliage if under trees or on really green grass
Noon sun/Sun overhead…5000-6500 Kelvin…………………….use Cloudy White balance
Flash photography in daylight 5500 Kelvin ………………………Use Flash White balance
Deep shade………………….6500 Kelvin…………………………Use cloudy/shade white balance
Shade in daylight 7500 Kelvin ………………………………......Use shade white balance
Heavy overcast, very dark shade 8000 to 10000 Kelvin………Use shade white balance plus 81a-85c glass filter

To set custom White balance: (Nikon)

Select a neutral coloured object to set your white balance
It’s best to avoid using a white target. The camera prefers grey..( Print yourself a grey card: In photoshop- File> New
Click on background square in toolbox
select 127;127;127 from color chart-Print)
If you use white in direct sunlight you'll always get a "No Gd" response from the camera because the Matrix meter is rendering it white instead of grey. Thus the trick is to select the centre-weighted meter when using a white reference in bright light and you'll get "Good" from a camera. Remember to set back to Matrix metering as soon as you're done.

Ok, so you are going to have problems if some images you want to make, are outside the dynamic range of the camera: So here's the plan for that:
With camera on tripod: meter for highlight, take a shot-then meter for shadows, take another shot.

In Photoshop:

1. Add lighter image to darker as a new layer, ,( click on Move tool, hold down "shift" button, and drag lighter image over to darker, then release)then:
2. Select> Color Range-Click highlights
3. Check “invert”, click “OK”.
4. Add layer mask. Click on layer mask
5.Filter> Blur> Gaussian Blur 250 pixels. Click "OK"
Flatten and save. You will get detail in highlights and shadows.

Now you know how to get perfect exposure-



Regards, Ken

[fletch]

Originally Posted by kencaleno

Where are you coming from? The following from original statement is white balance:

Pointing your camera at a white object to get a meter reading will attempt to turn that white object 18% gray if you meter off of it and do not compensate at all.

No its not 18% grey is to do with exposure as you well know. WB is an entirely different beast and you could use any grey to check that as long as it is grey.

Originally Posted by kencaleno

Mr Piano,Here's the secret to getting a perfectly exposed outdoor shot every time - (as long as your subject area is within the 5-stop dynamic range of the camera's metering system) ... [Long winded explanistion omited from quote for sanity's sake]

Wow that simple - So to get a perfect shot every time all I need to do is take 7 photos of every scene at every possible exposure value? Or do I just set that once and hope that the scene put in front of me matches my preset value from a completely different scene.

It seems your method is a bit "Photography by numbers" when actually it would serve someone better to understand the 'why' so they could apply that knowledge to the scene before them.

[kencaleno]

Originally Posted by fletch

No its not 18% grey is to do with exposure as you well know. WB is an entirely different beast and you could use any grey to check that as long as it is grey.



Wow that simple - So to get a perfect shot every time all I need to do is take 7 photos of every scene at every possible exposure value? Or do I just set that once and hope that the scene put in front of me matches my preset value from a completely different scene.

It seems your method is a bit "Photography by numbers" when actually it would serve someone better to understand the 'why' so they could apply that knowledge to the scene before them.

The why is explained fully-
The seven shots only happen once, just to calibrate the camera,to find out how it reads exposure-then you never need to do it again,ever,after that you use autobracket-why are you having so much difficulty in understanding your own language? Sorry but when you are qualified, as I am to teach photography,you need to understand photography in the first place

[fletch]

Originally Posted by kencaleno

The why is explained fully-
The seven shots only happen once, just to calibrate the camera,to find out how it reads exposure-then you never need to do it again,ever,after that you use autobracket-why are you having so much difficulty in understanding your own language? Sorry but when you are qualified, as I am to teach photography,you need to understand photography in the first place

So if I understand your method correctly I should work out what the bias of my cameras meter is once (using the 7 shots) and then dial that in as permanent exposure compensation. Say my on my Olympus the value was +0.3, what you are saying is that every shot from then on should be shot at +0.3? Really?

I don't need to concider the scene before me and evaluate the light sources and positions, then decide if I need to adjust exposure. Maybe I don't need to look at my subject and decide which meeting mode would be appropriate and maybe fire of a test shot to check my histogram. All that is now a thing of the past with your method? Simple as that? Wow - I can't wait to get home and set my expsoure compensation now that I have been shown the light by the great Kenneth Caleno.

Edit: Oh I missed out the bit about using autobracket. So on top of setting my camera perfectly for evey shot ever I now need to take three versions of it just in case? Well that sure does make it easier, definately living up the the great Ken Caleno's mantra of getting it right in camera.

[kencaleno]

Originally Posted by fletch

So if I understand your method correctly I should work out what the bias of my cameras meter is once (using the 7 shots) and then dial that in as permanent exposure compensation. Say my on my Olympus the value was +0.3, what you are saying is that every shot from then on should be shot at +0.3? Really?

I don't need to concider the scene before me and evaluate the light sources and positions, then decide if I need to adjust exposure. Maybe I don't need to look at my subject and decide which meeting mode would be appropriate and maybe fire of a test shot to check my histogram. All that is now a thing of the past with your method? Simple as that? Wow - I can't wait to get home and set my expsoure compensation now that I have been shown the light by the great Kenneth Caleno.

Edit: Oh I missed out the bit about using autobracket. So on top of setting my camera perfectly for evey shot ever I now need to take three versions of it just in case? Well that sure does make it easier, definately living up the the great Ken Caleno's mantra of getting it right in camera.

There are none so blind, as those who will not see. The exercise was if a perfect image was wanted everytime,this was how to get it-It's that simple. I would only use this method If I had a highly paying client wanting an exactitude of image within a limited time, as most of the time I get it right, anyway. regards

[mrpiano]

Hi Fletch (and Ken),

Yeah I was not thinking about white balance...I was thinking about the appropriate metering settings for a variety of different scenarios and how they impact exposure. Given there are a number of different metering options on most SLRs, I'm basically just trying to wrap my head around when to use the different types of metering and what the impact will be of each decision. Above all else, I was also opening the floor on the impacts of metering off a white object instead of something that the camera would see as "neutral" gray under the same lighting conditions...

Fletch, I've had good success so far with spot metering when outdoors, and have used the subject's face as the primary place to do my spot metering, so I agree with that approach and it seems widely embraced...

Sorry if my thread was misleading but certainly has been interesting to watch the dialogue unfold :-)

GG