In-Camera Metering | Newborn Photography

It's a hot Summer day here in Australia, and I'm coming down with a virus. The bad one. The one the whole family has had and the one I thought I might be lucky enough to escape! Thank goodness we have air conditioning! It makes illness much, much more bearable! Since I am not up to doing much today, I thought I would start on my new blogging initiative, whereby I plan to share all the little gold nuggets of education and 'ah ha' moments I've learnt and discovered over the years. I was originally going to pour it all out into a book but it hasn't happened (I started but it's a long way off finishing) so I figured why not educate for free instead, in return for some good old website traffic and SEO! Sounds great to me!

So, I'm going to start by talking about In-Camera Metering, for 'correct' Exposure, since most newborn photographers are using a DSLR and their in-camera meter to determine their Exposure. So, why the apostrophes around the word 'correct' in the sentence above? Well that's because you can expose a little lighter or darker and still turn out a wonderful image. Some photographers like particular shots to be darker and other shots lighter (think: a silhouette shot, for example) . When people refer to 'correct' Exposure, they should add a little note saying 'at 18% Grey' or something to that effect, as this is the 'fine print' of what it means to expose 'correctly'. I feel this is important to know as the term 'correct Exposure' could be mistakenly understood as 'the best' Exposure for an image. It most cases IT IS, but there are times when an underexposed or overexposed image is just as good, if not better. There are also photographers who like to 'expose to the right' (ETTR) or 'expose to the left' (ETTL). But I will touch on that, another day, when I discuss Histograms

18% Grey... what is that, exactly?

18% Grey is the reference point (or yard stick) your camera uses to gauge the brightness of objects. If you set your camera’s settings (ISO, Aperture and Shutter Speed) so that your camera is exposing 18% Grey correctly, then anything else you take a photo of (in the same lighting conditions) will be exposed correctly with those same camera settings.

So, where do you find 18% Grey and how do you expose for it? Well, you can buy 18% Grey Cards or Discs that are literally 18% grey in colour. You can also buy devices like the Expodisc which can be used to set correct Exposure and also correct White Balance. Or, like me, you can use your hand to determine correct Exposure since it is (conveniently) always there and accessible. I'll explain how I do this later in this article. The Expodisc is a lens cap type device that temporarily goes over your lens whilst taking a light meter reading and setting your Exposure. The Expodisc makes your camera see 18% Grey, so all you have to do is expose for the 18% Grey correctly.18% grey card
Above: 18% Grey Card from Mennon USA 
18% grey folding disc
Above: 18% Grey Disc
Above: Expodisc attached to lens


To set correct exposure with an 18% Grey Card you need the grey card to be sitting where the subject will be. However, to set the Exposure with an Expodisc, the photographer needs to stand where the subject will be and face towards the camera/shooting position.

You know when you’ve exposed for 18% Grey correctly when your in-camera light meter reads 0 (when pointed at an 18% Grey object/card). Less than 0 means the photo will be darker, any more than 0 means the photo will be lighter. Each number on the In-Camera Light Meter represents one ‘stop’. For example if you expose an 18% Grey Card at +2, using your in-camera light meter, then it is 'over-exposed' by 2 stops. By the way, be sure to set the focal length on your lens before taking an in-camera light meter reading as the wider your focal length, the more light that enters the camera and vice versa.

in camera light meter
Above: In-Camera Light Meter showing correct Exposure for 18% Grey


Once you have adjusted your camera settings to expose for 18% Grey correctly then watch what happens to the little marker on your In-Camera Light Meter when you move it away from your 18% Grey Card/Disc and point it at different areas in your shooting scene. It will jump all over the place - left and right! It will go to the left if you point your camera to a dark area in your scene and it will jump to the right if you point it to a bright area in your scene. What's happening here? This is the Light Meter reading the light and telling you how bright the given area is. When the marker moves to the right of the 0, the shooting scene is brighter than 18% Grey and when the  marker moves to the left of the 0, the shooting scene is darker than 18% Grey. Your Exposure is still correct - you haven't changed your ISO, Shutter Speed or Aperture, remember? To verify this, point your camera back to the 18% Grey Card/Disc again. See! The little marker is still at 0!

Earlier in this article I wrote about how I use my hand to set my Exposure (instead of an 18% Grey Card/Disc or device such as an Expodisc). This is because my hand is always there, and it's one less thing I have to carry around. I have learnt, through understanding the concept in the previous paragraph, that the marker on my In-Camera Light Meter will hover around +1 when pointed at the brightest area of skin on the back of my hand when my Exposure is correct at 18% Grey. So, the skin on the back of my hand (the area that has the most light on it) could be described as around 1 stop brighter than 18% Grey. I encourage you to experiment and find what your In-Camera Light Meter looks like on YOUR skin, when you're exposing 18% Grey correctly. If you have darker skin, then the little marker will probably sit to the left of the 0. 

In this article I talked about using your In-Camera Light Meter to expose your images and what happens when you point your camera at different areas in your shooting scene (bright areas, dark areas). What I haven't discussed, but will in the next article, is the various Metering Modes your camera has and how each Mode uses different areas in your shooting scene to read the light. 

Love and {Great} Light,

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