[voyager13]

Hi Guys,

The meter range of a K-5 is '0 to 22 EV'.
1. Please suggest a simple(beginners) way of understanding the EV in terms of when one is out in the field with just a camera and wanting to make the best exposure possible. What should be my first thoughts and steps towards the best possible exposure knowing the '0 to 22 EV' information on a K-5?
2. Also, how does dynamic range relate to EV?

[Adam]

Hi Guys,

The meter range of a K-5 is '0 to 22 EV'.
1. Please suggest a simple(beginners) way of understanding the EV in terms of when one is out in the field with just a camera and wanting to make the best exposure possible. What should be my first thoughts and steps towards the best possible exposure knowing the '0 to 22 EV' information on a K-5?
2. Also, how does dynamic range relate to EV?

The 0-22 figure just gives you the boundaries within which the camera's light meter works reliably. Less than 0 ev is a very dimly-lit room, while over 22 ev is close to the brightness of the sun.

If you have 14 stops of dynamic range then everything no part of the photo will be over or under exposed if and only if the difference between the lightest and the darkest point in the photo is less than or equal to 14 EV. In other words, say you're shooting outdoors and the darkest area is a rock at 5EV. So then everything from 5EV to 19EV would be kosher. You can buy a light meter that tells you the EV value, or it can be calculated based on shutter speed, ISO, and aperture.

[voyager13]

The 0-22 figure just gives you the boundaries within which the camera's light meter works reliably.

If you have 14 stops of dynamic range

I feel I need to have a good, thorough read on understanding dynamic ranges and EV's in practical terms, especially where those concepts are explained clearly using photographic examples. Any suggestions?

[Adam]

I feel I need to have a good, thorough read on understanding dynamic ranges and EV's in practical terms, especially where those concepts are explained clearly using photographic examples. Any suggestions?

I'm going to bed now, otherwise I'd like some samples. Try looking for photos of the sky or photos of blag dogs. That's when you really need dynamic range!

Adam
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[TenZ.NL]

In short:
DR is the intensity of light between pure black and pure white measured in stops (EV). 1 EV is a set lightlevel (say a lightbulb), so +1 EV is twice as bright as the initial lightbulb (if your lightbulb was 20Watt to begin with, it`s now 40Watts). So -1 EV is like cutting the lightintensity in half, like you dim the lightbulb by 50% and your lightbuld is now 10Watts.
Now in photography not all scenes have the same dynamic range. A landscape on a bright sunny day has more DR (EV stops) than the same scene on a cloudy day. Because the sunlight is stronger the shadows are deeper and the highlights are brighter, thus the total range of EV (stops) is bigger/wider.

Here`s something without getting too technical: Why understanding dynamic range is vital for travel photography - Photography - 25 Days Off | Make the most of your time off work! Travel itineraries and photography tips for full time workers.
And this one has some interesting links at the bottom: What is Dynamic Range? | The Circle of Confusion
And one more if you can`t get enough
The Online Photographer: More on Dynamic Range


Edit:
Also, EV (exposure value) is used to designated the luminance of a scene. To get the full out of a given scene the DR of that scene must not exceed the DR of the camera. (check your histogram)
(Shameless copy from Wikipedia)

[voyager13]

Those are great links you sent me Tenz, THANKS.

[Just1MoreDave]

You can use the camera's spot meter when you're out in the field with just the camera. In M mode, the bar meter shown is in Ev. In Av or Tv with a fixed ISO, you'll have to convert the displayed value to stops or Ev. For example, in Tv mode, the display says f2.8 at one point and f11 at another point. That's a 4 Ev difference. You can calculate the difference in any mode but when you allow more than one parameter to change, it's easy to run out of fingers and toes to count on. Remember the spot meter is designed to ignore everything except that spot. The other meter modes are looking at the whole frame and suggesting an exposure for that scene. The spot meter readings are only for the spot, so you have to consider how they'll work for the whole scene before shooting.

[voyager13]

You can use the camera's spot meter when you're out in the field

That's what I always try to do to measure the exposure, and than refer to the histogram to confirm if the exposure has been achieved within the confines of the camera's histogram, which also confirms that the dynamic range present is captured for that scene.
What I have been curious about is how to calculate the EV in any given scene (if I don't have a light meter) and apply that knowledge confidently knowing I must have captured the best possible exposure. I know one can do that using the zone system, but what if I am not comfortable(and confident) using the zone system, there must be some other way?

[Ponosby Britt]

What I have been curious about is how to calculate the EV in any given scene (if I don't have a light meter) and apply that knowledge confidently knowing I must have captured the best possible exposure.

1. Here's a good, detailed, free explanation The Ultimate Exposure Computer
2. I use the Sunny 16 Rule (which is based on EV 15) as an anchor point and mentally calculate the difference in stops. Sunny day EV 15, Hazy Sunny Day is EV14, Open Shade will be 13-12, etc..
3. With experience,especially if you're shooting a lot, your guesstimates will be pretty close. You can verify with the modern Polaroid aka Histogram. Shooting Raw on a K-5, the DR gives you some latitude.
4. Haven't used my camera meters in years. I do carry a Gossen Digisix, always set to ISO 100 and Incident. It gives me an EV value and I take it from there.

[derekkite]

Ultimate Exposure Computer

This is one way to do it. Another is to use a grey card, take a meter reading off of that, then set your camera.

[voyager13]

Excellent. Thanks for the link guys

[SteveM]

I've been shooting Pentax since 1981....and every camera has it's advantages but it's been a little wonky as of late. What I mean is EV from my K10d is not the EV from my K5. I can drop the shot 2 or 3 stops and push post processing with a K5 beyond my K10d.....which means sensitivity (Dynamic Range) means everything for EV.

[Ponosby Britt]

Ultimate Exposure Computer

This is one way to do it. Another is to use a grey card, take a meter reading off of that, then set your camera.

Or the palm of your hand, +2/3 stop.

"Grandpa, why are you taking a picture of your hand? I"m not, I'm getting a meter reading and I forgot my gray card"

[arcturus]

I'm still trying to grasp the concept here. Is exposure bracketing the same as EV bracketing?

[Ponosby Britt]

I'm still trying to grasp the concept here. Is exposure bracketing the same as EV bracketing?

EV simply means Exposure Value, how much light is falling on a subject.

Camera meters assume their measure of reflected light is the Exposure Value.

The amount of light reflected from an object is often different from how much light falls on an object, aka incident light.

If you use the camera's recommended exposure value (AE), black cats become gray, snow becomes gray, etc. EV compensation on a camera allows you to adjust the exposure for the reflective properties of the subject. It's why exposing +1 to 1.5 stops high for snow or a bright beach is recommended. Same with exposing -2/3 to 1 for a green forest or a black animal.

Bracketing makes multiples exposures, each with a slightly higher or lower exposure setting from the camera recommendation. Also useful for HDR.

If you bracket an exposure, you typically make at least 1 exposure a half stop or stop high, a nominal exposure and at least 1 exposure a half stop or stop low. If you're shooting slide film, its a practical approach. Negatives are more forgiving, as are digital raw files.

I skip the camera meter and use manual exposure based on an incident light meter reading or my best guesstimate of one. If I were making an HDR photo, trying to capture the maximum dynamic range of a scene with a lot of dynamic range, I'd bracket my manual exposure and combine the exposures in software.