Tips and tutorials

Intro to The Zone System & exposure

This tutorial is aimed at the beginner DSLR user. It’s suggested that you read my tutorials on aperture and shutter speeds first. 

The tips included here are the methods I use myself. They may be perfect for you or you may choose to adapt them. These tips are a starting point for those that have a digital camera but are still trying to get their head around what it can do.

For this tutorial I have used my Nikon D90 DSLR with my Nikkor 55-200 lens. The film speed was set at 200 ISO (except where indicated). Not having this equipment won’t stop you being able to follow along, you just need to be aware that your own test images may look different. In regards to light metering, I’ve used the systems built into the camera, rather than a hand-held meter.

Please note that modern DSLRs rarely meter in full stops. Your camera may meter in 1/2 or 1/3 increments (see aperture tutorial for full stops).

Example photos are as-is except for sharpening. If you click the photo it should open a larger example.



You may not realise this, due to it being such a sophisicated piece of equipment, but your camera can’t see the world in exactly the same way you do. Aside from the fact that they produce a 2 dimensional (flat) image, they don’t see colour. Instead, they register different shades of grey.

Modern cameras have built in and very complex metering systems. Those built into your camera are known as TTL (through the lens) and measure reflected light. This is the light reflected by the scene as opposed to actual light falling on the subject (known as incident light).

When you use your camera on auto mode, the built in meter (using the default or whatever type of metering you’ve set it to) will measure the light from many different areas in your scene, mash it all up and come up with an average that it thinks you’ll be happy with. For the most part, you may be happy with this photo – after all, cameras are getting quite fancy these days. But what about when you take a photo and it’s not quite right? What if it just doesn’t look like it does in real life?

Take for example a barbeque pit full of charred logs (an example I showed my friend). Taking a picture of it on automatic mode evened everything out. It didn’t capture the dark tones and intricacies of the burnt areas, it just made the whole scene (for want of a better term), meh.

One way to get around this issue is to try your camera’s bracketing system (BKT). Different cameras have this set up in different ways (read your manual) but essentially you can set the camera to take a series of shots in your preferred order. For example – Normal exposure, 1 stop darker, 1 stop lighter. The camera may change your shutter speed, aperture and/or ISO to achieve this. It’s not a bad setting to have and great to see what can be achieved and what your preferences are – ie you may find as a rule you prefer your shots slightly overexposed for that bright dreamy feel. However – the fact that the camera is automatically changing things like your aperture and film speed may affect the aesethtic you were going for. Therefore it’s important to know how to meter and manipulate your camera yourself.

This is where ‘The Zone System’ comes in handy. The Zone System was developed by photographers Ansel Adams and Fred Archer in the late 1930s, early 1940s. They were working with black and white photographic film, but the principals can be applied to your colour photography to add impact and render realistic scenes, as well as for taking digital pictures that you intend to turn black and white. You will find that by utilising the system, it will cut down on post processing time and create a far more dramatic image than if you just press the desaturate button.

There are 11 zones, from pure black 0 through to pure white x (10). ‘Perfect’ exposure is deemed to be zone 5 – middle grey 18% – though perfect is subjective of course.

The Zone System (via PhotoAnswers.co.uk) developed by Ansel Adams.

There are a few ways you can measure middle grey. You could buy a Kodak Grey Card or tool like a Xpobalance (these are great) or you could improvise.

Pretty early on in my photography (I’ve been shooting since I was 15/16 and am now 30), I found I was always forgetting to pack my grey card or it’d get grotty or mistaken as just a piece of junk by those that didn’t know better. As such, I learnt to take my readings in a way many other photographers consider an emergency method. Whatever –  it has rarely let me down and it’s a good place to start. I meter from the palm of my hand, or when I have a model, from their cheek.

After a long time, most of this stuff comes as second nature and you can instinctively look at a scene with a fairly good idea of what settings to start with. It will come, it just takes practice, practice, practice!

You may prefer to get your grey card, xpobalance or light meter and that’s fine, in fact I do recommend it and yes I have a handheld meter too, but more often than not, this is how I meter:

    • I set the camera to manual mode (M).
    • I choose my ISO (film speed) and my WB (white balance) depending on my lighting scenario. More often than not I’m outside photographing people or flowers, so personally I like to choose 200ISO (sometimes 400) so that I can enlarge with fine grain/noise – it’s easy to add grain, not so easy to remove it!, and set my WB to daylight. You can get pretty technical with the D90 and cameras like it and get into Kelvins (light temperature) and fine tune the colour spectrum but for now, let’s say daylight.
    • I don’t always do this, but at this point you might like to take a picture of what the camera thinks your scene should be.
    • I take  the palm of my hand (I’m pale caucasian, if you have darker skin you will have to refer to the zone chart) and put it in the same light as my subject or, if I have a captive model, I’ll walk right up and meter off their face. Fill the viewfinder, making sure the light is even and the same as the subject. Press the shutter button halfway down and take note of the shutter and aperture/f number displayed. If your focus is set to manual here, another option is to actually take the shot – then the settings are there in your data to refer back to.
    • Now I switch back to manual mode and dial in the settings the camera’s told me and take a photo. I check it in my viewfinder, seeing what my preference is. By default, average caucasian skin falls into zone 6 – it’s already 1 stop brighter than middle grey. If my model is wearing white or has beautiful pale skin or hair, I may now chose to change my aperture or my shutter speed so that I get nice bright tones with detail instead of muddy grey. Alternatively if they have dark hair or are wearing black clothing – perhaps a corset with lace detail, I may choose to underexpose slightly so that I can accurately capture that the clothing is black but with detail.
© Kell Rowe www.blackcurrantphotography.com.au

Changing my shutter speed helped me get detail in the petals.

Bringing this information back to my flower photography – let’s look at the frangipani flower I photographed. I know that there are thin veins and texture in the flower petals. The camera doesn’t know this. It can look at the flower and go ‘cool! middle grey. Everyone loves grey!’ It might decide that it’s doing me a favour by reading all that dark green in the picture and compensates by changing the settings – resulting in a brighter image. All of a sudden I’ve lost my highlight detail. I don’t want to change my aperture here – I like that it’s got a shallow depth of field (blurry background) and want to keep that. Instead, I choose to make my shutter speed higher/faster thus letting in less light. My shadows are darker, letting my white flower stand out more and I have detail in my petals again.

© Kell Rowe www.blackcurrantphotography.com.au

3 dramatically different images just by changing my shutter speed.

You’ll notice that in some of the photo examples I have changed my aperture and in other examples I’ve changed my shutter speed, sometimes both. Why chose one method over another? Aperture affects depth of field (DOF). In the shots of the hibiscus bud above, my aperture (and therefore the depth of field) remain constant and I use my shutter to control the exposure. However there are situations where having a consistent or deliberately fast or slow shutter speed is preferable. With this choice of telephoto lens, I have been advised that when hand holding the camera, I should choose a shutter speed equal or greater to the maximum focal length of the lens to help avoid camera shake and blurry photos. Everyone is different and every lens is different (I didn’t use the rule this time), but it IS a good rule of thumb and helps with the example. If my shutter speed is more critical than my depth of field, I can use the aperture to control the light. When both need to remain consistent then other options are to change the ISO and introduce or subtract ambient and focal lighting.

© Kell Rowe www.blackcurrantphotography.com.au

Changing my aperture affects the DOF & the tones of my image.

A really good exercise, and one that you undertake fairly early on when learning about black and white film photography or the basics in general, is to go and find yourself a high key and a low key scene and practice exposing for both so that you can see the differences between what the camera says is right, and what your human knowledge of the scene is. For practicing, chose non reflective objects – trust me for now – it’s hard enough to nail exposure when starting out without having to deal with reflections! Try photographing some dark chocolate or the folds in some black satin or alternatively, a white flower or meringues or marshmallows on a white background.  The aim is to capture the detail and correct tone in that object without it fading into the background. You want your picture to have a similar tonal range to how you see the object with your own eyes. Measure for middle grey and then use the information in the zone chart to find the right zone for your subject.

As always, practice before you shoot anything important, shoot something that interests you so that you enjoy the process, and experiment.

Have fun!

Further reading and reference material –

http://en.wikipedia.org/wiki/Zone_System
http://en.wikipedia.org/wiki/Light_meter
http://en.wikipedia.org/wiki/Through-the-lens_metering
http://en.wikipedia.org/wiki/Middle_gray
http://www.photoanswers.co.uk/Advice/Search-Results/Photopedia/Zone-System/

Photography – London, Stone & Upton.

This blog article was written by Kell Rowe at Blackcurrant Photography. Publication on sites other than http://www.blackcurrantphotography.com.au and http://www.blackcurrantphotography.wordpress.com has not been authorised. 

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2 thoughts on “Intro to The Zone System & exposure

  1. Pingback: 12 months of Blackcurrant. Farewell 2011. « Blackcurrant Photography – Perth, Australia. Fine art, creative portraiture, nature photography & Australian gifts.

  2. Pingback: A flash of improvisation (tutorial) « Blackcurrant Photography – Perth, Australia. Fine art, creative portraiture, nature photography & Australian gifts.

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