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metering

This tag is associated with 6 posts

Correct Exposure Using Your Meter

When you buy your first DSLR camera you really have no idea what any of the specifications mean. When reading about ISO, Spot Meter, Cropped Sensor, AF Points they might as well be written in a different language. Don’t be discouraged, learning the basics and what terms mean what is the easy part. Perfecting your skill will take a lifetime! It’s the journey that is so intriguing to us!

When I started searching for my first DSLR camera back in 2009 my photographer friend’s advice was to go as high as my budget could on the ISO, but make sure it had a spot meter. There are two ways you can have a light meter (in camera or handheld) His old camera had the handheld light meter and he says they’re a must. So that is where I started my search which lead me to purchasing the Canon XSi over the Canon XS

There are usually four types of metering. All cameras are different and might use slightly different names when referring to the light metering on the camera. For instance Canon says “evaluative metering” while Nikon calls the same thing “Matrix Metering”. These pictures below are pictures from the Canon 60D metering modes. So let’s get down to the basics of photography 101, making sure we’re using the proper meter to get the correct exposure for our picture.

Evaluative Metering

The camera looks at the entire scene and sets the exposure automatically to best suite the scene. When all things are average go for Evaluative Metering. Whenever I am on aperture priority I always have my metering set to evaluative. Sometimes I might adjust the exposure compensation. But for the most part the scene is usually pretty average

Partial Metering

Partial Metering covers about 6.5% of the view finder area at the center. Good to use when the background is a lot brighter than the subject because of back lighting. However I never use this one. If dealing with a high contrast situation like that I would just switch it to spot metering which covers 2.8% of the entire scene.

Spot Metering

If I have a high contrast situation like a subject sitting in front of a window or a sunset I will switch to Manual mode and change my metering to spot metering. Spot metering will meter the light right in the center of your frame in an area that covers about 2.8% of the entire scene. Think of it like the size of a quarter.

Center-weighted average

The metering for center-weighted is weighted at the center and then takes an average of the entire scene. Typically the center 80% of the cells are considered more important than the outlying regions. Personally I don’t use this one either.

The two metering modes I use on my camera to measure light are:

1. Spot Metering / Manual – If my scene has high contrast I meter using spot meter.
2. Evaluative Metering / Aperture Priority – If my scene is very average I meter using evaluative metering

What about you? Do you have a favorite trick or tip about metering and how you shoot, please add!

Note – if you’re shooting on any of the automatic shooting modes you will not be able to change your light meter, the camera will do it for you.

Learn By Doing – Meter using dusky blue sky

Assignment #21 – Meter using dusky blue sky

Last week we talked about metering for a mostly green image by going -2/3 on the meter. This week we are giving the Sky Brothers a try! According the Bryan Peterson from his book “Understanding Exposure”  you can take a meter reading from the dusky blue sky, recompose your picture and shoot! “Brother Dusky Blue Sky” is good for shooting city or country scenes at dusk.

I went out tonight at dusk to take some pictures.  For the most part I liked the warm color it brought by metering off the sky. I wish I took a comparison picture to show you what my camera saw if I metered from the scene in front on me. I can tell you that every time I recomposed my shot after metering from the sky my meter said I was wrong. I am sure I had a lot of folks downtown wondering what I was taking a picture of when I aimed for the sky!

This next one I just liked all the lines and color still the same warm color

The building pictures I took I felt came out a bit dark when I exposed for the blue sky.  The light changes so quickly as day comes to a close.  Within just a few minutes the light felt like it changed as did the color blue in the sky. I sure did enjoy myself walking around town at dusk. They always say the light is best in the morning and evening. Boy was the city beautiful tonight with the soft light bouncing around everywhere. No kids tonight just me…. It was very relaxing in deed.

Curious to see if the dusky blue sky trick will work for you? You can post at the bottom of this post or on DigitalCamFan FaceBook wall. If you have questions about “Learn By Doing” Please refer to the guideline page. If you have no questions post away!

 

Understanding Exposure Compensation

On this weeks “Learn by Doing” we wanted to try out the idea presented in Bryan Peterson’s book “Understanding Exposure“. The question what happens when your image is mostly green. His idea meter your image at -2/3 stop!

Metering still confuses me! Even though exposure seems like photography 101 I think I will be trying to understand it for my entire photography career! I still have to think about it every time I come to a tricky situation when my scene is mostly white black or high contrast.  I have to think add light to light or add dark to dark. Now I have a new trick in my pocket to think about when my image is mostly green.

This tutorial is a great tutorial that talks about just that… exposure compensation.  At about 6 minutes into the video he shows us how sensitive our meter is. He first takes a picture of Erica with mostly white, but her black hair is down. The next picture is her hair pulled back with just that change he had to adjust his exposure!

Now here is the good stuff that pertains to this weeks assignment! At about 8 minutes he does an awesome tutorial on how to adjust your exposure compensation! He explains how to change exposure compensation in aperture priority and shutter priority as well as what to do if you’re in manual mode!

Take a moment to check out some of their other videos… great job!

Learn by Doing this week was from the book

18 % Reflectance

I have to see it, and do it to actually get it. If you learn visually like I do then maybe this will explain the meter  a little better.

Here is a visual of what your camera sees when looking at a scene made up of mostly snow.  Apparently a histogram is important!  Check out this visual from the cameras view point shot at f stop 8 / ISO 100 / shutter speed 1600 metered off exactly what the camera saw as middle gray:

Now if I open up 2 stops  the shutter speed is now @400! Add light to light

When your meter is presented with black or white it freaks out a bit thinking way too much! For instance in the picture above I want the snow to be white when I look at the histogram it says white.

Assigment #2 – Metering off a Gray Card, black

Last week we talked about metering off a gray card when your scene was mostly white. So of course this week we are going to push forward and understand black.  So pull out that gray card again!

Learn by Doing!

Take 2 pictures one with a gray card and one without. If you don’t have a gray card use anything in the house that is a middle gray like a gray pillow a gray jacket etc.

Picture 1 – Make sure your scene is mostly black. Turn your camera to manual  Take the picture according to what your camera meter sees as a perfectly exposed picture.

Picture 2 – Put your gray card in front of your picture, adjust your exposure until it is on the 0. When you move your gray card out of the picture your meter will tell you this is the wrong exposure. Going ahead and take the picture, but don’t change your meter.

Here is a picture I took of my son’s DSi case. The one on the left is metered to the camera exposure which looks more gray than black. The one on the right is metered off a gray card and definitely looks black.

 

 

 

 

 

 

 

A little bit about our meter:

Our camera is deigned to render subjects middle gray or 18%. Black reflects approximately 9% so the camera over exposes trying to make your picture middle gray (18%) I try to remember this saying when I have a scene that is mostly black – add dark to dark! Since the camera is going to over expose we need to adjust accordingly.  The opposite is true for white, since the camera is going to underexpose we need to add light to light.

Here is the picture I took last week that shows all three colors. White, gray and black.  When I zoomed in on the individual colors they all took on a gray color because our camera sees in neutral gray. This is starting to sink in as I keep doing these experiments. Our camera does not see in color or in black and white but rather a neutral gray.

 

 

 

 

 

 

 

 

 

 

 

 

Assignment #1 – Metering off a Gray Card

Assignment #1 – Take a 2 pictures one with a gray card and one without. If you don’t have a gray card use anything you have that  is middle gray could be a gray shirt or just a gray piece of paper.

Picture 1. Find something where your entire scene is more white than anything else could be snow, bed spread zoom in on a white dress. Turn your camera to manual and expose correctly. This is what your camera sees.

Picture 2. Hold your gray card in front of your scene turn your camera to spot meter if you don’t have that use partial meter. Meter off the gray card. Remove the gray card from the picture.  Now don’t change your exposure even though it has a different reading and take the picture.

I wrote a post about how to meter in manual if you want to take a peek!

Here is the picture I came up with in my backyard using snow well what little bit of snow we have right now!

A little bit about our meter:

Our camera is designed to render subjects middle gray or 18%.  Most pictures tend to be average if you’re at the park with grass, trees, kids running around in different clothes. This would create a very average scene in your camera. Now if you put a black cat on a black chair your camera will overexpose to make your subject gray. Just the opposite if you have a scene of just white snow your camera will underexpose making your snow look gray.

Meters still confuse me and I  have to think what the heck am I suppose to do! Here is an example I took of three colors white, gray and black on aperture priority. I let the camera meter decide what it was going to see. The first picture with all three colors you can tell there are three colors. But when I zoomed in on the picture so it just showed the white black or gray they all just took on a different shade a gray. The camera thought way too white need to adjust, or way too black need to adjust the only one that felt just right was the gray itself.