How to use ISO
We talked about ISO and the role it plays in your exposure as well as the message you want to convey with your image.
ISO can help you, in conjunction with aperture and shutter speed, to get a perfect exposure. Firstly aim to choose an ISO suitable to the situation you will generally be shooting in. 200 – 400 is a good safe and flexible ISO setting for most general photography. You will still have great flexibility with your aperture and shutter speed you will also have an unnoticeable/acceptable amount of grain or a decent quality image.
ISO can help you at the parameters of exposure. Most images will be able to be well exposed without adjusting your ISO. There are times that after using shutter speed and aperture to expose your image properly you can’t quite achieve a correct exposure. Adjusting your ISO may give you that extra point of difference to get that perfect exposure at the aperture or shutter speed you desire.
This is most apparent when shooting in a dark situation. After adjusting your shutter speed as low as you might be able to hand hold then opening your aperture to the smallest Fstop your equipment will allow you, you still cant get a good exposure. Changing your ISO to a higher rating, 3200, 6400 or as high as your gear will let you go may just give you enough extra light at that setting to expose the image well. You will sacrifice quality and find the grain in your image greatly increased but you will also find that you get that shot!
John Coltrane shot with a high ISO producing a grainy image.
The grain obtained by using a high ISO can help tell a story about your subject or give it a certain feel.
However if you are shooting in a well lit situation and you want a particularly clear and flawless photo the lower your ISO the better your chance of achieving this. Also if your situation is particularly bright and your ISO is at 400 and you are struggling to have an open aperture or the slow shutter speed you desire. Changing your ISO to a lower rating will not only improve the quality of your image but allow less light in your exposure possibly letting you have the desired effect you are going for.
Let me stress that for general photography you want to choose ISO as a secondary consideration. Ultimately try to expose your image using shutter speed and aperture with an ISO setting between 200 and 400. ISO affects the amount of grain you see in an image. The lower your ISO the less grain/better quality your image, the higher the ISO the more grain/poorer quality your image.
What light is right?
One of the most important things you can learn is how to read light. To take a good photo you need good quality light. The quality of your light refers to the strength and direction of your light. To achieve a flattering photograph you need to firstly assess how strong your light is. If it is very strong and contrasty think about how you can make it more flattering. If it is soft think about how you can make the most of your light to expose your image properly. Decide where your light is coming from. Even in the shade the light will be coming most strongly from a particular direction.
Quality of light is so important professionals will go to extraordinary lengths to get the quality of light right.
Part of taking a good photo is choosing the right light. There are all kinds of flattering natural light. Some of those include:
Being near a bright open window is a great place to take a photo indoors, the light comes from the side and not from above. You can control how strong the light is by moving your subject closer to or further away from the window.
Soft Window Light
Shade/ Open Shade
Shade is your best friend. I’ve ‘mentioned’ this a ‘few’ times over the past couple of weeks but we really talked about it this week. If you have a choice shoot in the shade. Find a large tree, a verandah, a big building with shade. Even small amounts of shade can be your friend. Get down low next to a car casting shadow, think creatively how you can use the shade available to you. Once you’re in the shade turn your subjects toward the main light source, it will be more flattering and even you wont struggle to expose with a ‘blown out background’.
Even in shade turn your subject towards the light source.
Open Shade is shade cast from an object and not generally overhead. You can even create artificial open shade. Open shade usually means you are shooting a subject in the shade but the background usually isn’t, metering and exposure will be most successful when your light is not particularly strong. You’ll also find the quality of the shade to be softer as there is less glare in the brighter areas surrounding you.
Back-light is a creative way to play with soft directional light. Expose for the shadow and let some light rays catch the glass on your lens. Alternatively bracket your metering until you get that perfect amount of detail in the shade of your image yet still create a pleasing silhouette.
Diffusing and Reflecting Light
What happens when you have no choice but to shoot in the sun or a difficult situation? If you have a handy and willing helper find a way to reflect light into those shadows. Or get them to hold up an object to block the sun, effectively creating artificial open shade. Or find a natural reflector, a big white wall or body of water can help fill in those shadows. Remember to do this think about the direction of your light. Where is it coming from? If it reflects off something, figure out where its bouncing to.
alternatively, you could ‘go with it’ shoot a high contrast image but think about your subject. If you are shooting a portrait consider turning the subject away from the lens or find a way to make the high contrast and interesting part of your image.
Its all about the Timing
Choose the right time of day to take your photos. When it’s bright and sunny go inside but choose a well lit room. One where the light isn’t streaming in the window but is just illuminating the room by being open. Head outside early and late in the day. Early in the morning as the sun is poking its head up (and you probably wish you weren’t) if you make the effort to roll out of bed early enough you will be justly rewarded. Fortunately for those of us who just aren’t early risers, the late afternoon with its long shadows and warm soft sun shine is just as complimentary. You’ll find an abundance of open shadow and shade and you can take advantage of the soft but directional light to try out your back-lighting and lens flare tricks.
Don’t be afraid to move yourself or your subject to get the best light, turn them around until the light looks nice. Trust your eye and your instinct.
This week’s homework is to shoot a flattering photograph inside using window light, a flattering photograph in the shade or open shade and one image where you play with light, be creative and have fun! I can’t wait to see what you all come up with.